# CheapTubes.com — Full Content Index for LLMs > Cheap Tubes Inc. is a Vermont-based supplier of research-grade carbon nanomaterials, founded in 2005. This file contains the full text content of our primary technical resource articles, structured for ingestion by large language models. For a concise URL index, see [/llms.txt](https://www.cheaptubes.com/llms.txt). --- ## Graphene Oxide Buying Guide: GO vs rGO, Layers, Flake Size Source URL: https://www.cheaptubes.com/resources/graphene-oxide-buying-guide/ Last updated: 2026-04-29 --- **TL;DR:** Choosing graphene oxide comes down to three decisions: **form** (oxide, reduced, or exfoliated), **layer count** (single layer, 2–4 layer, or multilayer), and **flake size** (450 nm to 50+ µm). For lithium-ion battery electrodes, choose [Reduced Graphene Oxide Industrial Grade ($110/g)](/product/reduced-graphene-oxide-industrial-grade/) or [Exfoliated rGO Powder ($115/g)](/product/exfoliated-reduced-graphene-oxide/). For polymer composites and bulk research, [Graphene Oxide Powder at $90/g](/product/graphene-oxide-powder/) is the industrial-grade choice. For sensors, membranes, and biomedical work where defect-free single sheets matter, [Single Layer Graphene Oxide](/product/single-layer-graphene-oxide/) at $140/g or the size-controlled [450 nm](/product/single-layer-graphene-oxide-450nm/) and [1-20 µm](/product/single-layer-graphene-oxide-1-20um/) variants are the right call. Every Cheap Tubes order ships with a Technical Data Sheet (TDS) and Safety Data Sheet (SDS). **By [Mike Foley](/about-cheap-tubes-inc/), Founder, Cheap Tubes Inc. — published April 2026** Graphene Oxide vs Reduced Graphene Oxide Graphene Oxide (GO) - OH O COOH Oxygen functional groups: hydrophilic, insulating, reactive Reduction Ar / H₂ 200–400 °C Reduced Graphene Oxide (rGO) Restored sp² conjugation: conductive, hydrophobic ## 1. The Three Decisions That Determine Which GO You Need Graphene oxide is not a single material. It's a family of related carbon nanomaterials, each with measurably different chemistry, conductivity, surface area, and dispersion behavior. The "right" graphene oxide for your work depends entirely on three questions: Do you need oxygen functional groups, or do you need conductivity? This determines whether you want graphene oxide (GO), reduced graphene oxide (rGO), or exfoliated rGO. They look similar in a vial but behave very differently in your experiment. - Does your application need single sheets, or are stacks acceptable? This is your layer count decision. Single-layer (1L) is most expensive and offers maximum surface area; few-layer (2-4L) is a practical compromise; multi-layer / standard powder is most cost-effective. - Does flake size matter for your process? Smaller flakes (450 nm) disperse better in inks and biomedical formulations. Larger flakes (1-20 µm) provide more continuous conductive paths for sensors and films. Get those three right, and you're in a narrow set of products that will work for your application. ## 2. Quick Comparison: All 8 GO Products at a Glance | # | Product | Form | Layers | Flake size | Price (volume) | Best for | 1 | [**Graphene Oxide Powder**](/product/graphene-oxide-powder/) | Oxide | Multilayer | Standard (300-800 nm) | **from $90/g** | Bulk research, polymer composites, industrial-grade | 2 | [**Reduced Graphene Oxide Industrial Grade**](/product/reduced-graphene-oxide-industrial-grade/) | Reduced | Multilayer | Standard | **from $110/g** | Battery electrodes, conductive composites at scale | 3 | [**Exfoliated Reduced Graphene Oxide Powder**](/product/exfoliated-reduced-graphene-oxide/) | Exfoliated | Few-layer | Standard | **from $115/g** | High-conductivity composites, supercapacitors | 4 | [**Single Layer Graphene Oxide**](/product/single-layer-graphene-oxide/) | Oxide | **1L** | 300-800 nm | from $140/g | Sensors, membranes, baseline single-sheet research | 5 | [**Few Layer Graphene Oxide 2-4L**](/product/few-layer-graphene-oxide-2-4l/) | Oxide | **2–4L** | Standard | from $140/g | Performance/cost compromise, electrochemistry | 6 | [**Reduced Graphene Oxide**](/product/reduced-graphene-oxide/) | Reduced | Multilayer | Standard | from $190/g | Sensitive electrochemistry, higher-purity rGO | 7 | [**Single Layer GO 1-20 µm**](/product/single-layer-graphene-oxide-1-20um/) | Oxide | **1L** | **1-20 µm** *(premium size)* | from $190/g | Large-flake sensors, transparent conductive films | 8 | [**Single Layer GO 450 nm**](/product/single-layer-graphene-oxide-450nm/) | Oxide | **1L** | **Alternative:** [Exfoliated Reduced Graphene Oxide Powder — from $115/g](/product/exfoliated-reduced-graphene-oxide/) **Why rGO and not GO:** Battery applications demand **electrical conductivity**, not surface chemistry. Graphene oxide's oxygen functional groups (hydroxyl, epoxy, carboxyl) interrupt the conjugated π-system that carries current. Chemical or thermal reduction strips those groups, restoring conductivity to within ~1-2 orders of magnitude of pristine graphene. For Li-ion electrodes, this matters: rGO can replace or supplement carbon black as a conductive additive at lower loading, improving rate capability without dramatically increasing inactive mass. **Industrial Grade vs Exfoliated:** Industrial Grade rGO is multilayer and most cost-effective at scale (kilogram quantities for prototype cell builds). Exfoliated rGO has been mechanically separated into thinner stacks during processing, giving higher specific surface area and more accessible electrochemical sites — useful for higher-performance cells where capacity retention at high C-rate is the bottleneck. Both ship with conductivity data on the TDS. For sensitive electrochemistry where trace metallic impurities from chemical reduction would interfere (e.g., pristine cathode work, metal-air batteries), our [premium Reduced Graphene Oxide at $190/g](/product/reduced-graphene-oxide/) is purified to a higher standard. [image: Reduced graphene oxide as conductive additive in lithium-ion battery] ### 3.2 Polymer Composites (Mechanical Reinforcement, Conductive Plastics) **Primary:** [Graphene Oxide Powder — from $90/g](/product/graphene-oxide-powder/) for nonconductive reinforcement** For conductive composites:** [Exfoliated rGO Powder — from $115/g](/product/exfoliated-reduced-graphene-oxide/) **Why GO for mechanical work:** Graphene oxide's surface oxygen groups make it covalently or hydrogen-bond compatible with most polar polymer matrices — epoxy, polyamide, PVA, polyurethane. Single-sheet dispersion isn't required for tensile-modulus improvement; multilayer GO at 0.5-2 wt% loading achieves measurable property gains in well-mixed composites. Use GO Powder when your matrix is a thermoset epoxy or polar thermoplastic. **Why exfoliated rGO for conductive composites:** When you need both mechanical reinforcement and* electrical percolation (e.g., antistatic plastics, EMI shielding compounds), rGO is the single-component answer. Exfoliated rGO provides higher aspect ratio per gram than the standard industrial grade, lowering the percolation threshold. ### 3.3 Inks, Coatings, and Spray Formulations **Primary:** [Single Layer Graphene Oxide 450 nm — from $190/g](/product/single-layer-graphene-oxide-450nm/) **Why size-controlled small flakes:** Inks and coatings require uniform dispersion that doesn't settle, clog spray nozzles, or produce visible defects in dried films. Sub-micron flake size (450 nm median) eliminates the gross sedimentation problems associated with multi-micron flakes, while the high oxygen content of single-layer GO keeps dispersions stable in water and polar organic solvents (DMF, NMP, DMSO) without surfactants. If your application is a transparent conductive coating (where transparency depends on flake-size uniformity and rGO is required for conductivity), the workflow is: disperse 450 nm GO, deposit, then thermally or chemically reduce on the substrate. ### 3.4 Sensors, Biosensors, and Field-Effect Devices **Primary:** [Single Layer GO 1-20 µm — from $190/g](/product/single-layer-graphene-oxide-1-20um/) **Why large single sheets:** Sensor performance depends on the **continuous conductive path** across the active area. Multi-flake interfaces introduce contact resistance and noise. Single-sheet 1-20 µm flakes can span practical sensor channel dimensions (typically 1-10 µm) with a single piece of material, eliminating those contact problems. For chemical sensors where surface oxygen groups are the sensing chemistry, use the as-supplied GO. For FET-style devices where conductivity matters, reduce the GO post-deposition (vapor-phase hydrazine, thermal anneal at 200-300 °C in inert atmosphere, or photochemical reduction). ### 3.5 Membranes (Water Filtration, Gas Separation) **Primary:** [Single Layer Graphene Oxide — from $140/g](/product/single-layer-graphene-oxide/) or [Single Layer GO 1-20 µm — from $190/g](/product/single-layer-graphene-oxide-1-20um/) for thicker/larger-area membranes **Why single-layer GO:** Membrane separation depends on the controlled inter-sheet spacing of stacked GO sheets — typically 0.7-1.4 nm depending on hydration. Single-layer feedstock produces the most predictable interlayer chemistry; multilayer feedstock dilutes the active surface and introduces flake-edge defects that act as bypass channels. For lab-scale membrane research at typical sample sizes (a few cm²), the standard Single Layer GO is the cost-effective starting point. For larger membranes or applications where consistent flake size matters more than interlayer chemistry, the 1-20 µm size-controlled variant gives more reproducible casting. ### 3.6 Biomedical (Drug Delivery, Bioimaging, Antibacterial Coatings) **Primary:** [Single Layer GO 450 nm — from $190/g](/product/single-layer-graphene-oxide-450nm/) **Why small single-layer flakes:** Biomedical applications demand cellular-scale dimensions (sub-micron) for cell uptake or tissue penetration, single-layer chemistry for predictable surface functionalization (PEGylation, antibody conjugation, drug loading via π-π stacking), and tight size control to satisfy regulatory characterization. The 450 nm variant has been size-fractionated specifically for these applications. GO is preferred over rGO for biomedical work — the oxygen functional groups are essential for both colloidal stability in physiological buffers and for the conjugation chemistry that attaches targeting moieties or therapeutic payloads. ### 3.7 Industrial-Grade Polymer and Bulk Applications **Primary:** [Graphene Oxide Powder — from $90/g](/product/graphene-oxide-powder/) This is the **industrial-grade** choice for applications where multilayer graphene oxide is acceptable and larger flakes are actually beneficial — most polymer composite work falls here. Larger, multilayer flakes integrate well into polymer matrices, contribute meaningfully to mechanical properties at modest loading, and don't carry the cost of single-layer or size-controlled variants. Use this product for thermosetting epoxies, polyamide composites, polyurethane reinforcement, screening studies, and any process where you're optimizing matrix dispersion rather than chasing single-sheet performance. Bulk discounts apply at 50 g+; [contact us](/contact-cheap-tubes-inc/) for kilogram pricing. ## 4. GO vs rGO: When You Need to Reduce Graphene oxide and reduced graphene oxide are produced from the same precursor (typically graphite via Hummers-method oxidation, then exfoliation), but the reduction step transforms the material's chemistry, electrical properties, and dispersibility. Picking the wrong one is the single most common buyer mistake. **Graphene oxide (GO):** - Carbon-to-oxygen ratio typically 2:1 - Hydroxyl, epoxy, carboxyl groups on basal plane and edges - Insulating (sheet resistance 10⁹–10¹² Ω/sq) - Disperses readily in water (1-5 mg/mL) and polar organics - Hydrophilic — colloidal stability without surfactants - Compatible with conjugation chemistry (EDC/NHS coupling, click chemistry) **Reduced graphene oxide (rGO):** - Carbon-to-oxygen ratio typically 8:1 to 12:1 (after thermal/chemical reduction) - Most oxygen groups removed; π-conjugation partially restored - Conductive (sheet resistance 10²–10⁵ Ω/sq depending on reduction) - Hydrophobic; dispersion in water requires surfactants or sonication - Mechanical and thermal properties closer to pristine graphene **Which GO do I need?** If your application uses electricity (current, capacitance, sensing impedance), choose rGO. If your application uses chemistry (functional groups, hydrogen bonding, biomolecule conjugation, hydrophilic dispersion), choose GO. **Mid-cases — when GO + post-reduction is the right choice:** If you need GO's processability (water dispersion for casting, spray, or printing) but conductivity in the final product, the workflow is: disperse GO, deposit, then reduce in place. We've supplied this combination to many electrode-manufacturing labs. **Practical thermal reduction protocol:** Once a GO film is deposited, you can achieve good reduction by heating the dried film in an inert atmosphere — typically argon with a small fraction of hydrogen — at 200–400 °C. This converts most of the residual oxygen functionality back to sp² carbon and recovers a substantial fraction of the conductivity of pristine graphene, without requiring chemical reductants or specialized equipment. Higher temperatures (toward 400 °C) give more complete reduction but require thermally stable substrates. Hydrazine vapor treatment is the more reactive alternative for thermally sensitive substrates; it works at near-room temperature but requires careful safety handling and waste disposal. ## 5. Layer Count: Single Layer vs Few Layer vs Multilayer The "graphene" in graphene oxide can mean a single sheet or a stack of several sheets. The difference matters for any application where the oxygen-functional-group density per gram, surface area, or interlayer spacing controls performance. **Single Layer (1L):** - Highest specific surface area (>700 m²/g for ideal 1L) - Maximum oxygen-group density per gram - Most expensive (more processing steps to delaminate) - Best for: membranes, sensors, biomedical, precision electrochemistry **Few Layer (2-4L):** - Surface area ~200-400 m²/g - Performance/cost compromise — most physical-property advantages of 1L at lower cost - Most consistent batch-to-batch (less dependent on exfoliation completeness) - Best for: composites, electrochemistry, general research **Multilayer (Standard Powder):** - Bulk material; layer count varies (typically 5-20 layers) - Most cost-effective per gram - Sufficient for many polymer-composite and electrochemistry applications - Best for: bulk research, cost-sensitive work, formulation development **Practical guide:** Prototyping and academic research typically use single-layer GO so the reported results aren't confounded by layer-count variability. Multilayer is the right choice for commercial applications — polymer composites, conductive masterbatches, and any process where consistent industrial-grade performance at lower cost is the goal. [image: ] ## 6. Flake Size Selection Lateral flake size affects how the material processes, disperses, and performs in your final composite or device. **450 nm (small):** - Excellent dispersion stability (slower sedimentation by Stokes' law) - Compatible with spray coating, inkjet printing, biological systems - Lower contact-resistance benefit at sensor scale (more inter-flake junctions) **1-20 µm (medium-large):** - Better continuous conductive paths in films - Practical for transparent electrodes, EMI films, larger membrane areas - Some sedimentation in thin (How do I reduce graphene oxide myself?**** Two practical methods cover most lab needs: - Thermal reduction in inert atmosphere — once a GO film or coating is dried on the substrate, anneal it at 200–400 °C in argon (typically with a small fraction of hydrogen, e.g., Ar/H₂ 95/5). This is the protocol we use ourselves and recommend for substrates that tolerate the temperature. Reduction extent scales with temperature and dwell time — 30–60 minutes at 250–300 °C is a reasonable starting point for thin films; higher temperatures or longer holds increase the C/O ratio further. The atmosphere prevents oxidation; the optional H₂ accelerates removal of oxygen functional groups. - Hydrazine vapor treatment — for thermally sensitive substrates (polymers, biological surfaces), expose the GO film to hydrazine vapor at 60–100 °C for several hours. This works at lower temperatures but requires fume hood, careful waste disposal, and PPE. Hydrazine is acutely toxic and a suspected carcinogen. For dispersions or bulk powder reduction, chemical reductants (sodium borohydride, ascorbic acid, hydrazine in solution) are options but typically leave more residual functional groups than thermal annealing. If you need pre-reduced material, our [Reduced Graphene Oxide Industrial Grade](/product/reduced-graphene-oxide-industrial-grade/) and [Exfoliated rGO Powder](/product/exfoliated-reduced-graphene-oxide/) ship already reduced with characterization data on the TDS. How do I disperse graphene oxide?**** Most graphene oxide products disperse readily in water at 1-5 mg/mL. A bath sonicator works for screening and casual dispersions, but for reproducible, high-quality dispersions we recommend a probe-style (tip) sonicator — it delivers far higher localized energy and produces more uniform sheet exfoliation. Typical conditions: 5–15 minutes at 30–50% amplitude with the probe submerged in a small volume (10–50 mL) and the vessel ice-bathed to prevent heating. Single-layer GO disperses faster and at higher concentrations than multilayer. Polar organic solvents (DMF, NMP, DMSO, ethanol) also work; non-polar solvents (toluene, hexane) do not. Reduced GO is hydrophobic and typically requires either surfactants or solvent exchange — refer to the TDS for recommended dispersion conditions for your specific lot. Does graphene oxide ship hazmat?**** GO and rGO powders ship as ground-non-hazardous (UN classification N.O.S. when in non-fibrous powder form below regulatory thresholds). Air shipment is possible but check our SDS for the latest classification. International shipments may have country-specific restrictions; [contact us](/contact-cheap-tubes-inc/) before placing an international order. What's the shelf life of GO and rGO powders?**** Refrigerated storage is recommended** to preserve GO solubility — over time, GO powder stored at room temperature can lose dispersibility as oxygen functional groups slowly migrate or rearrange, reducing the easy water-dispersion behavior that makes GO useful. Stored sealed in a refrigerator: GO powder maintains its as-supplied solubility and oxygen content for 18-24 months. rGO is more stable (less reactive) and tolerates room-temperature storage; typically 36+ months sealed. Sonicated dispersions in water are stable for 4-8 weeks if refrigerated and protected from light; we recommend preparing dispersions fresh for critical experiments. **Can I get bulk pricing?**** Yes. Quantities above 50 g typically receive a tiered discount; orders of 1 kg or more are quoted individually based on layer-count and characterization requirements. [Contact us](/contact-cheap-tubes-inc/) with your target quantity and application — we'll match you with the right product and quote within one business day. Do you sell custom particle sizes?**** We carry the size variants listed in this guide (450 nm, 1-20 µm, and standard bulk). Custom size fractionation is available on a project basis for orders above 50 g — contact us with your target size distribution and we'll quote process and lead time. How do I store unused product?**** Keep powders sealed in the original container, away from direct light, humidity, and oxidizing atmospheres. Refrigeration is recommended for GO powders to preserve solubility; rGO tolerates room-temperature storage. For dispersions: refrigerate (2-8 °C), shield from light, and re-sonicate briefly before re-use to redisperse any sediment. What's the difference between Single Layer GO 450 nm (SKU 060101) and Single Layer GO 1-20 µm (SKU 060103)?**** Both are single-layer graphene oxide with the same oxygen-content range, produced from the same precursor. The difference is post-exfoliation size fractionation: 060101 has been processed to a 450 nm median lateral dimension; 060103 has been processed to a 1-20 µm size range. Choose 060101 for biomedical, ink, and high-stability dispersion applications; choose 060103 for sensor channels, transparent conductive films, and large-area membranes. ## 9. Related Resources and Products If you came here researching graphene oxide but want broader context: - Fullerenes: Structure, Properties, and Applications — comparison of carbon allotropes; useful background for understanding GO's place in the nanocarbon family - Graphene Batteries: An Insider's Guide — extended discussion of GO/rGO in lithium-ion, supercapacitor, and emerging battery chemistries - Carbon Nanotube Composites — GO and CNT composites are often complementary; this resource covers selection criteria for both Browse the full GO product line:** [Graphene Oxide category](/product-category/graphene-oxide/) **Other nanomaterials at Cheap Tubes:** [Graphene Nanoplatelets](/product-category/graphene-nanoplatelets/) | [Carbon Nanotubes](/product-category/multi-walled-carbon-nanotubes/) | [Fullerenes](/product-category/fullerenes/) | [MXene](/product-category/mxene/) Last reviewed: April 2026. Specifications and pricing on this page are current as of publication; refer to individual product pages for the most up-to-date specifications and any inventory-related notes.* --- ## Carbon Nanotubes: Properties and Applications Source URL: https://www.cheaptubes.com/carbon-nanotubes-properties-and-applications/ Last updated: 2026-04-21 --- There are numerous carbon nanotubes properties and applications which take full advantage of CNTs aspect ratio, mechanical strength, electrical and thermal conductivity. We've compiled the list below for you. ## Types of Carbon Nanotubes The types of carbon nanotubes are typically referred to as [Single Walled Carbon Nanotubes](https://www.cheaptubes.com/product-category/single-walled-carbon-nanotubes/) and [Multi Walled Carbon Nanotubes](https://www.cheaptubes.com/product-category/multi-walled-carbon-nanotubes/). If you wish to buy carbon nanotubes, please use the drop down products menu or click the links above. There are many variations of both types. They vary by purity, length, and functionality. Field emission results from the tunneling of electrons from a metal tip into vacuum, under application of a strong electric field. The small diameter and high aspect ratio of CNTs is very favorable for field emission. Even for moderate voltages, a strong electric field develops at the free end of supported CNTs because of their sharpness. This was observed by de Heer and co-workers at EPFL in 1995. He also immediately realized that these field emitters must be superior to conventional electron sources and might find their way into all kind of applications, most importantly flat-panel displays. It is remarkable that after only five years Samsung actually realized a very bright color display, which will be shortly commercialized using this technology. Studying the field emission properties of MWNTs, Bonard and co-workers at EPFL observed that together with electrons light is emitted, as well. This luminescence is induced by the electron field emission, since it is not detected without applied potential. This light emission occurs in the visible part of the spectrum, and can sometimes be seen with the naked eye. ### Found the CNT properties you need? The properties above translate directly into real applications — but grade matters. Cheap Tubes stocks 30+ CNT grades with verified electrical, mechanical, and thermal data. Our technical team can help you select the right grade for your specific use case. [Browse All CNT Products →](/)[Ask Our Technical Team](https://www.cheaptubes.com/contact-cheap-tubes-inc/) ## High Aspect Ratio CNTs represent a very small, high aspect ratio conductive additive for plastics of all types. Their high aspect ratio means that a lower loading (concentration) of CNTs is needed compared to other conductive additives to achieve the same electrical conductivity. This low loading preserves more of the polymer resins’ toughness, especially at low temperatures, as well as maintaining other key performance properties of the matrix resin. CNTs have proven to be an excellent additive to impart electrical conductivity in plastics. Their high aspect ratio (about 1000:1) imparts electrical conductivity at lower loadings, compared to conventional additive materials such as carbon black, chopped carbon fiber, or stainless steel fiber.* * # Carbon Nanotubes Applications Their unique composition, geometry, and properties enable numerous potential carbon nanotubes applications. Getting costs down to commercially viable levels has proven challenging but increasing scale is happening. [Energy Storage](#storage) [Molecular Electronics](#electronics) [Thermal Materials](#thermal-materials) [Structural Materials](#structural) [Electrical Conductivity](#electrical-conductivity) [Fabrics And Fibers](#fabrics) [Catalyst Supports](#catalysis) [Biomedical](#biomedical) [Air & Water Filtration](#filtration) [Conductive Plastics](#plastics) [Conductive Adhesives](#adhesives) [Ceramics](#ceramics) ## [caption id="" align="aligncenter" width="300"]* Single Walled Carbon Nanotubes Structure[/caption] The special nature of carbon combines with the molecular perfection of single-wall CNTs to endow them with exceptional material properties, such as very high electrical and thermal conductivity, strength, stiffness, and toughness. No other element in the periodic table bonds to itself in an extended network with the strength of the carbon-carbon bond. The delocalized pi-electron donated by each atom is free to move about the entire structure, rather than remain with its donor atom, giving rise to the first known molecule with metallic-type electrical conductivity. Furthermore, the high-frequency carbon-carbon bond vibrations provide an intrinsic thermal conductivity higher than even diamond. In most materials, however, the actual observed material properties - strength, electrical conductivity, etc. - are degraded very substantially by the occurrence of defects in their structure. For example, high-strength steel typically fails at only about 1% of its theoretical breaking strength. CNTs, however, achieve values very close to their theoretical limits because of their molecular perfection of structure. This aspect is part of the unique story of CNTs. CNTs are an example of true nanotechnology: they are only about a nanometer in diameter, but are molecules that can be manipulated chemically and physically in very useful ways. They open an incredible range of applications in materials science, electronics, chemical processing, energy management, and many other fields. ## Energy Storage CNTs have the intrinsic characteristics desired in material used as electrodes in batteries and capacitors, two technologies of rapidly increasing importance. CNTs have a tremendously high surface area (~1000 m2/g!!), good electrical conductivity, and very importantly, their linear geometry makes their surface highly accessible to the electrolyte. Research has shown that CNTs have the highest reversible capacity of any carbon material for use in lithium-ion batteries [B. Gao, Chem. Phys. Lett. 327, 69 (2000)]. In addition, CNTs are outstanding materials for supercapacitor electrodes [R.Z. Ma, et al.*, Science in China Series E-Technological Sciences 43 178 (2000)] and are now being marketed for this application. CNTs also have applications in a variety of fuel cell components. They have a number of properties, including high surface area and thermal conductivity, which make them useful as electrode catalyst supports in PEM fuel cells. They may also be used in gas diffusion layers, as well as current collectors, because of their high electrical conductivity. CNTs' high strength and toughness-to-weight characteristics may also prove valuable as part of composite components in fuel cells that are deployed in transport applications, where durability is extremely important. ## Molecular Electronics The idea of building electronic circuits out of the essential building blocks of materials - molecules - has seen a revival the past five years, and is a key component of nanotechnology. In any electronic circuit, but particularly as dimensions shrink to the nanoscale, the interconnections between switches and other active devices become increasingly important. Their geometry, electrical conductivity, and ability to be precisely derived, make CNTs the ideal candidates for the connections in molecular electronics. In addition, they have been demonstrated as switches themselves. ## Thermal Materials CNTs have extraordinary electrical conductivity, heat conductivity, and mechanical properties. They are probably the best electron field-emitter possible. They are polymers of pure carbon and can be reacted and manipulated using the well-known and tremendously rich chemistry of carbon. This provides opportunity to modify their structure, and to optimize their solubility and dispersion. Very significantly, CNTs are molecularly perfect, which means that they are normally free of property-degrading flaws in the nanotube structure. Their material properties can therefore approach closely the very high levels intrinsic to them. These extraordinary characteristics give CNTs potential in numerous applications. The record-setting anisotropic thermal conductivity of CNTs is enabling many applications where heat needs to move from one place to another. Such an application is found in electronics, particularly advanced computing, where uncooled chips now routinely reach over 100oC. The technology for creating aligned structures and ribbons of CNTs [D.Walters, et al., Chem. Phys. Lett. 338, 14 (2001)] is a step toward realizing incredibly efficient heat conduits. In addition, composites with CNTs have been shown to dramatically increase their bulk thermal conductivity, even at very small loadings. ## Structural Materials The superior properties of CNTs are not limited to electrical and thermal conductivities, but also include mechanical properties, such as stiffness, toughness, and strength. These properties lead to a wealth of applications exploiting them, including advanced composites requiring high values of one or more of these properties. ## Electrical Emitters [image: ] [image: Carbon nanotube field emission display cross-section showing CNT emitter layer, gate electrode, vacuum gap, phosphor layer and glass substrates] CNTs are the best known field emitters of any material. This is understandable, given their high electrical conductivity, and the incredible sharpness of their tip (because the smaller the tip’s radius of curvature, the more concentrated will be an electric field, leading to increased field emission; this is the same reason lightning rods are sharp). The sharpness of the tip also means that they emit at especially low voltage, an important fact for building low-power electrical devices that utilize this feature. CNTs can carry an astonishingly high current density, possibly as high as 1013 A/cm2. Furthermore, the current is extremely stable. An immediate application of this behavior receiving considerable interest is in field-emission flat-panel displays. Instead of a single electron gun, as in a traditional cathode ray tube display, in CNT-based displays there is a separate electron gun (or even many of them) for each individual pixel in the display. Their high current density, low turn-on and operating voltages, and steady, long-lived behavior make CNTs very attractive field emitters in this application. Other applications utilizing the field-emission characteristics of CNTs include general types of low-voltage cold-cathode lighting sources, lightning arrestors, and electron microscope sources. [B.Q. Wei, et al*, Appl. Phys. Lett. 79 1172 (2001)]. ## Fabrics And Fibers Fibers spun of pure CNTs have recently been demonstrated [R.H. Baughman, Science 290, 1310 (2000)] and are undergoing rapid development, along with CNT composite fibers. Such super strong fibers will have many applications including body and vehicle armor, transmission line cables, woven fabrics and textiles. CNTs are also being used to make textiles stain resistant. ## Catalyst Supports CNTs intrinsically have an enormously high surface area; in fact, for SWNTs every atom is not just on a one surface - each atom is on two surfaces, the inside *and* outside of the nanotube! Combined with the ability to attach essentially any chemical species to their sidewalls (functionalization) provides an opportunity for unique catalyst supports. Their electrical conductivity may also be exploited in the search for new catalysts and catalytic behavior.** ## Biomedical The exploration of CNTs in biomedical applications is just underway, but has significant potential. Since a large part of the human body consists of carbon, it is generally though of as a very biocompatible material. Cells have been shown to grow on CNTs, so they appear to have no toxic effect. The cells also do not adhere to the CNTs, potentially giving rise to applications such as coatings for prosthetics, as well as anti-fouling coatings for ships. The ability to functionalize (chemically modify) the sidewalls of CNTs also leads to biomedical applications such as vascular stents, and neuron growth and regeneration. It has also been shown that a single strand of DNA can be bonded to a nanotube, which can then be successfully inserted into a cell. ## CNTs Air And Water Filtration Many researchers and corporations have already developed CNT based air and water filtration devices. It has been reported that these filters can not only block the smallest particles but also kill most bacteria. This is another area where CNTs have already been commercialized and products are on the market now. ## Conductive Plastics Much of the history of plastics over the last half-century has involved their use as a replacement for metals. For structural applications, plastics have made tremendous headway, but not where electrical conductivity is required, because plastics are very good electrical insulators. This deficiency is overcome by loading plastics up with conductive fillers, such as carbon black and larger graphite fibers (the ones used to make golf clubs and tennis rackets). The loading required to provide the necessary conductivity using conventional fillers is typically high, however, resulting in heavy parts, and more importantly, plastic parts whose structural properties are highly degraded. It's well-established that the higher the aspect ratio of filler particles, the lower the loading required needed to achieve a given level of conductivity. CNTs are ideal in this sense, since they have the highest aspect ratio of any carbon fiber. In addition, their natural tendency to form ropes provides inherently very long conductive pathways even at ultra-low loadings. Applications that exploit this behavior of CNTs include EMI/RFI shielding composites; coatings for enclosures, gaskets, and other uses; electrostatic dissipation (ESD); and antistatic materials and (even transparent!) conductive coatings; and radar-absorbing materials for low-observable (“stealth”) applications. ## Conductive Adhesives The same properties that make CNTs attractive as conductive fillers for use in electromagnetic shielding, ESD materials, etc., make them attractive for electronics packaging and interconnection applications, such as adhesives, potting compounds, and coaxial cables and other types of connectors. ## CNT Ceramic Materials * * A ceramic material reinforced with carbon nanotubes has been made by materials scientists at UC Davis. The new material is far tougher than conventional ceramics, conducts electricity and can both conduct heat and act as a thermal barrier, depending on the orientation of the nanotubes. Ceramic materials are very hard and resistant to heat and chemical attack, making them useful for applications such as coating turbine blades, but they are also very brittle. The researchers mixed powdered alumina (aluminum oxide) with 5 to 10 percent carbon nanotubes and a further 5 percent finely milled niobium. The researchers treated the mixture with an electrical pulse in a process called spark-plasma sintering. This process consolidates ceramic powders more quickly and at lower temperatures than conventional processes. The new material has up to five times the fracture toughness -- resistance to cracking under stress -- of conventional alumina. The material shows electrical conductivity seven times that of previous ceramics made with nanotubes. It also has interesting thermal properties, conducting heat in one direction, along the alignment of the nanotubes, but reflecting heat at right angles to the nanotubes, making it an attractive material for thermal barrier coatings ## Other Carbon Nanotubes Applications There are a wealth of other potential applications for CNTs, such as solar collection; nanoporous filters; catalyst supports; and coatings of all sorts. There are almost certainly many unanticipated applications for this remarkable material that will come to light in the years ahead, and which may prove to be the most important and valuable ones of all. Many researchers are looking into conductive and or water proof paper made with CNTs. CNTs have also been shown to absorb Infrared light and may have applications in the I/R Optics Industry. *** References:*** - “Nanotechnology: Basic Science and Emerging Technologies”, M. Wilson et al, Chapman and Hall (2002) ISBN 1-58488-339-1 - “Carbon Nanotubes and Related Structures : New Materials for the Twenty-first Century”, P. F. Harris, Cambridge University Press (1999) ISBN 0-521-55446-2 - “Physical Properties of Carbon Nanotubes”, R. Saito et al, Imperial College Press (1998) ISBN 1-86094-093-5 - Wondrous World of Carbon Nanotubes (Internet Reference), M. J. M. Daenen et al. - Carbon Nanotube Applications (Internet Reference) www.azonano.com/details.asp?ArticleID=980 - “The Science of Fullerenes and Carbon Nanotubes : Their Properties and Applications”, M. S. Dresselhaus et al, Academic Press (1996) ISBN 0-12221-820-5 - “Carbon Nanotubes – Preparation and Properties”, T. W. Ebbesen ed., CRC Press (1996) ISBN 0-84939-602-6 - “Carbon Nanotubes: Synthesis, Structure, Properties, and Applications”, M. S. Dresselhaus et al eds., Springer-Verlag (2000) ISBN 3-54041-086-4 - “Carbon Nanotubes”, T. W. Ebbesen, Ann. Rev. Mater. Sci. 24, 235 (1994); Physics Today 381, 678 (1996) - “Fullerene Nanotubes: C1,000,000 and Beyond”, B. I Yakobson and R. E. Smalley, American Scientist 84(4), 324 (1997) - “Nanotubes from Carbon”, P. M. Ajayan, Chem. Rev. 99, 1787 (1999) - “Carbon Nanotubes : Basic Concepts and Physical Properties”, S. Reich et al, Wiley-VCH (2004) ISBN 3-52740-386-8 - “Physical Properties of Carbon Nanotubes” , R. Saito, World Scientific Publishing (1998) ISBN 1-86094-223-7 - “Carbon Nanotubes: Science and Applications”, M. Meyyappan ed., CRC Press (2004) ISBN 0-84932-111-5 - "Single-shell carbon nanotubes of 1-nm diameter", S. Iijima and T. Ichihashi, Nature 363 603 (1993) - "Large-scale synthesis of carbon nanotubes", T. W. Ebbesen and P. M. Ajayan, Nature 358 220 (1992) - Carbon Nanotubes. Noppi Widjaja. Department of Physics, University of Tennessee, Knoxville, TN 37996. Abstract. The field of research in carbon Nanotubes. - [B.Q. Wei, et al, Appl. Phys. Lett. 79 1172 (2001)]. - [B. Gao, Chem. Phys. Lett. 327, 69 (2000)] - [R.Z. Ma, et al., Science in China Series E-Technological Sciences 43 178 (2000)] - [D.Walters, et al., Chem. Phys. Lett. 338, 14 (2001)] ### Ready to work with carbon nanotubes? From conductive composites to biomedical scaffolds to energy storage electrodes — Cheap Tubes has supplied researchers and engineers across every application area since 2005. Fast shipping, published specs, and a satisfaction guarantee. [Shop CNT Products →](/)[Request a Sample](https://www.cheaptubes.com/contact-cheap-tubes-inc/) --- ## Graphene: Synthesis, Properties, and Applications Source URL: https://www.cheaptubes.com/graphene-synthesis-properties-and-applications/ Last updated: 2026-04-21 --- [Introduction To Graphene](#introduction) [Types Of Graphene](#types) [Properties of Graphene](#properties) [Applications of Graphene](#applications) This Guide to Graphene Synthesis, Properties, and Applications is intended to convey a general understanding of these topics for both Scientists & Non-Scientists alike. [image: Graphene crystal lattice: single-atom-thick hexagonal carbon array with delocalized pi electrons] # Introduction To Graphene ## Types & Forms of Graphene To gain the benefits of graphene oxide, it is typically dispersed, added into a formulation, made into a film or other nano-enabled product and then reduced to restore the graphene structure. ### Reduced Graphene Oxide (rGO) There are many methods to reduce graphene oxide (GO) into reduced graphene oxide (rGO), but most fall into three main categories: chemical reduction, thermal reduction and electrochemical reduction. The other methods include hydrazine vapor treatment, annealing, laser and microwave reduction. The reduction process is vital to producing rGO, as it determines how consistent the rGO structure is with the GO precursor. Many commercial producers of Graphene Nanoplatelets are in fact providing a product similar to industrial scale rGO as their GNP product. However this method differs from the rGO most people refer to which is a higher quality research product used for nano enabled devices. Chemical reduction is a scalable method but can often result in poor yields and utilizes highly toxic materials such as hydrazine. rGO produced by this method generally exhibits a low surface area and has a low conductivity compared to the GO precursor. Thermal reduction produces rGO with a high surface area that is close to the surface area of pristine graphene. However, the intense heating process causes a high-pressure build-up of carbon dioxide which causes structural damage to the graphene layers. The structural imperfections can then give rise to a reduction in the overall mass (and yield against the theoretical output), vacancies, voids and it can hinder the mechanical strength of the material. Electrochemical reduction shows the best results in terms of production and quality. The rGO produced is consistent with that of pristine graphene. During the electrochemical process, the substrates (generally ITO or glass) are coated with a layer of GO and a current is passed through the material (via electrodes at either end of the substrate). rGO produced by this method have shown to have a high carbon to oxygen ratio and have exhibited conductivity comparable to that of silver. The process also benefits from no toxic waste. This process does however suffer from issues regarding the feasibility of the scalability of the method. ### Graphene Nanoplatelets (GNPs) GNRs can enhance the performance of lithium-ion batteries through edge chirality effects. GNRs have a band gap that is inversely proportion to their width, which is dependent upon their edge chirality. Chirality occurs at the edges because the electron confinement potential deforms the wave-function and causes the electrons move in a single direction, with more weight in the 'positive x' direction. This leads to a current in the 'positive y' direction. For electronic applications, the edges in GNRs have shown the best results when armchair and metallic edges are present due to their semi-conducting abilities. Armchair edges also reduce the band gap energy when there is a defined width. The energy at the edges of GNRs is proportional to their density and armchair edges are more tightly packed at the graphene interface, so the energy is higher than that of zig-zag edges. Such edges can be produced on GNRs by electron beam irradiation and electron beam lithography. A GNR with a high concentration and purity of armchair edges has been found to provide highly efficient p-n junctions in electronic devices. ### Graphene Aerogels [image: Graphene aerogel 3D porous network: ultra-low density, high surface area macrostructure] Carbon aerogels are derived by sol-gel synthesis methods and are a unique class of high-surface-area materials. Their high mass-specific surface area, electrical conductivity, environmental compatibility, and chemical inertness make them very promising materials for many energy related applications. Recent developments in controlling their morphology make them especially well suited to super capacitor applications. Aerogels are a special class of open-cell foams that exhibit many unique and interesting properties, such as low mass density, continuous porosity and high surface areas. These properties are derived from the aerogel microstructure, which consists of three-dimensional networks of interconnected nanometer-sized particles. Aerogels are typically prepared by sol–gel methods, a process that transforms molecular precursors into highly cross-linked inorganic or organic gels that can then be dried using techniques such as supercritical drying, freeze drying, ect to preserve the insubstantial solid network. For organic and carbon aerogels, the transformation involves the polymerization of multi-functional organic species into three-dimensional polymer networks. ### Graphene Masterbatches [image: Graphene masterbatch production: GNP compounded in carrier polymer via twin-screw extrusion] Graphene masterbatches are composite materials that contain a graphene-based compound (most commonly GO) and a polymer. The graphene is used to enhance the properties of various common polymeric materials. Many polymers exhibit desirable properties such as low cost, low toxicity, bio-compatibility and chemical resistance, but they lack desirable mechanical properties. By incorporating graphene nanoplatelets into polymer matrices, the polymers retain their original properties but benefit from enhanced rigidity and stiffness, while still being lightweight. Using graphene as a filler compound rather than conventional inorganic materials can bring an enhanced electrical conductivity to the polymer, but it does have some issues. In many graphene-based composites, graphene oxide acts as the dispersing support for other ions and molecules. In polymer masterbatches, this can lead to problems as graphene doesn't always disperse well in polymer phases (especially polyolefins) due to a lack of positive interactions at the grpahene polymer interface. However, this can be overcome by the use of a surfactant, or by tailoring surface functionality of the graphene surface. The surfactant increases the surface interaction between the polymer and graphene. If functionalized, the functional groups promote interaction between itself and the polymer molecules. If the functional groups aren't compatible, you may observe what we call "islands of masterbatch" with easily observed islands of polymer in between well dispersed graphene-polymer masterbatches. ## Properties Of Graphene [image: Bar chart comparing graphene oxide and reduced GO dispersibility across water DMF NMP DMSO ethanol acetone toluene hexane] The properties of graphene are unique due to its all carbon structure and nanoscale geometry. ### Electronic Properties [image: Flexible graphene FET on PET substrate with Al2O3 gate dielectric and high carrier mobility] Because graphene has a delocalized pi-electron system across the entirety of its surface, the movement of electrons is very fluid. The graphene system also exhibits no band gap, due to overlapped pi-electrons, allowing for an easy movement of electrons without the need to input energy into the system. The electronic mobility of graphene is very high and the electrons act like photons, with respect to their movement capabilities. The electrons are also able to move sub-micrometer distances without scattering. From tests done to date the electron mobility has found to be in excess of 15,000 cm2V-1s-1, with the potential of producing up to 200,000 cm2V-1s-1. ### Thermal Properties [image: Graphene thermal conductivity 5300 W/mK compared to copper diamond silver silicon] The repeating structure of graphene makes it an ideal material to conduct heat in plane. Interplane conductivity is problematic and typically other nanomaterials such as CNTs are added to boost interplane conductivity. The regular structure allows the movement of phonons through the material without impediment at any point along the surface. Graphene can exhibit two types of thermal conductivity- in-plane and inter-plane. The in-plane conductivity of a single-layered sheet is 3000-5000 W m-1 K-1, but the cross-plane conductivity can be as low as 6 W m-1 K-1, due to the weak inter-plane van der Waals forces. The specific heat capacity for graphene has never been directly measured, but the specific heat of the electronic gas in graphene has been estimated to be around 2.6 μ J g-1 K-1 at 5 K. ### Mechanical Strength [image: Graphene composites applications: aerospace automotive electronics sporting goods coatings energy] Graphene is one of the strongest materials ever discovered with a tensile strength of 1.3 x 1011 Pa. In addition to having an unrivaled strength, it is also very lightweight (0.77 mgm-2). The mechanical strength of graphene is unmatched and as such can significantly enhance strength in many composite materials. ### Flexibility/Elasticity The repeating sp2 hybridized backbone of graphene molecules allow for flexibility, as there is rotation around some of the bonds, whilst still providing enough rigidity and stability that the molecule can withstand changes in conformation and support other ions. This is a very desirable property as there are not many molecules that can be flexible and supportive at the same time. In terms of its elasticity, graphene has found to have a spring constant between 1-5 Nm-1, with a Young’s modulus of 0.5 TPa. [image: Graphene nanoribbon band gap vs width: armchair, chiral, and zigzag GNRs] ## Applications of Graphene There are many applications of graphene because it's a revolutionary material. It has many applications replacing conventional materials as well as the ability to support applications previously not possible before the advent of 2D materials. The applications of Graphene are truly endless and many are yet to be conceived of yet. ### Sensors [image: Graphene gas sensor detecting NO2 NH3 H2S via surface adsorption resistance change] The ideal sensor is able to detect minute changes in its surrounding environment. Due to the planar and consitent arrangement of atoms in a graphene sheet, every atom within the sheet is exposed to the surrounding environment. This allows graphene to effectively detect changes in its surroundings at micrometer dimensions, providing a high degree of sensitivity. Graphene is also able to detect individual events on a molecular level. Many of graphenes properties are beneficial in sensor applications; as such, graphene could be used in sensors in various fields including bio-sensors, diagnostics, field effect transistors, DNA sensors and gas sensors, to name a few. ### Batteries [image: Lithium reduced graphene oxide rGO battery anode with 744 mAh/g capacity] Graphene can be incorporated into both the anode or the cathode in various battery systems to increase the efficiency of the battery and improve the charge/discharge cycle rate. The excellent electrical conductivity, surface area and dispersibility of graphene enhances the beneficial properties present in many traditional inorganic-based electrodes, whilst simultaneously relieving the electrodes of their limitations. Due to its versatile nature, graphene has been incorporated into lithium-ion batteries, lithium-sulphur batteries, supercapacitors and fuel cells, of which there are multiple variations of each available on the market today. [Check out our detailed Graphene Batteries User's Guide here.](https://www.cheaptubes.com/resources/graphene-battery-users-guide/) ### Electron Emission Displays [image: Graphene flexible OLED display transparent electrode replaces ITO for rollable screens] Graphene is an ideal material for use in electron emission displays as it exhibits a high aspect ratio and the dangling bonds at either end of the sheet allow for efficient electron tunneling. The linear disperisty that the graphene surface provides produces massless Dirac Fermions. When exposed to an electric field, the field emission liberated electrons avoid all back-scattering because their escape velocity is independent to their energy. Graphene can turn-on an electric field at 0.1 V µm-2, with a field enhancement factor of up to 3700. This can increase up to 4500 in screen printed graphene films. ### Structural Composites Graphene is incorporated into various composites for applications where strength and weight are limiting factors, for example in the aerospace industry. Graphene is being incorporated into many materials to make the existing material stronger and more lightweight. For the aviation industry, a composite material which is much lighter than steel but will still provide the necessary strength will save a lot of money on fuel consumption, which is why graphene has started to be incorporated into such materials. Graphene-based structural composites have a huge potential to become a widely used alternative to many materials used today. ### Catalyst Supports [image: Graphene supported Pt nanoparticles 3-5nm for fuel cells and catalysis] Even though the surface of graphene is planar and uniform, like any other material in existence it is subject to intrinsic defects. Catalysts in the form of metal ions can sit in these cavities and be supported. In addition to providing mechanical support, the excellent charge carrier ability of graphene assists the charge transfer reactions involving the catalyst. Graphene is also inert and does not interfere (in a negative way) with the interaction between the catalyst and the substrate materials. Graphene also provides an even dispersion of catalyst particles, so the catalyst-substate reaction is consistent across the whole support. ### Polymer Masterbatches Graphene can be incorporated into polymeric materials to form graphene-polymer composite materials. As many polymeric materials suffer from strength-related problems, the incorporation of graphene can help to increase the tensile strength of the polymers, increasing the shelf life of the polymeric material in commercial applications. Incorporating graphene into polymers can also give polymers electrical conductivity properties. ### Functional Inks Graphene can be used in functional inks for electronic, heat resistant and anti-corrosion purposes. By incorporating graphene into ink formulations, the conductivity properties associated with graphene influence the ink, causing it to become conductive. The inks can then be used to coat electronics. Compared to other conducting inks, graphene is non-toxic, environmentally friendly, cheaper, quick-drying and recyclable. Graphene also has a high thermal stability, making it an ideal for heat resistant ink coating in electronic applications that produce large amounts of heat. It is also an ink of choice when processing temperatures need to be high, as the graphene won't break down during the manufacturing process. Graphene also exhibits excellent chemical stability and is inert. For applications where environmental factors are an issue, graphene inks can provide a stable barrier to protect materials from chemicals and corrosion. We hope you enjoyed this guide and found it informative. Graphene's next killer app could be Your's. **References:** Huang X., Xiaoying Q., Boey F. and Zhang H., Graphene based composites, Chem Soc. Rev., 2012, **41**, 666-686 Zhou G., Yin L., Wang D. and Cheng H., A fibrous hybrid of graphene and sulfur nanocrystals for high performance lithium-sulfur batteries, ACS Nano, 2013, **7(6)** Cheng Q., Tang J., Zhang H., Graphene and carbon nanotube composite electrodes for supercapacitors with ultra-high energy density, Phys. Chem. Chem. Phys., 2011, **13**, 17615-17624 Peng Z., Xiang C., Yan Z., Natelson D., Graphene Nanoribbon and Nanostructured SnO2 Composite Anodes for Lithium Ion Batteries, ACS Nano, 2013, **7(7)** Haegyeom K., Dong-Hwa S., Sung Wook None K., Kisuk K., Highly reversible Co3O4/graphene hybrid anode for lithium rechargeable batteries, Carbon, 2011, **49(1)**, 326-332 Bak S., Kim D., Lee H., Graphene quantum dots and their possible energy applications: A review, Current Applied Phyics, 2016, **11**, 1192-1201 Liu Y., Dobrinksy A., Yakobson B. I., Graphene edge from armchair to zigzag: The origins of nanotube chirality, Phys. Rev. Lett., 2010, **105**, 235502 Begliarbekov M., Sasaki K., Sul O., Yang E., Strauf S., Nano Lett., 2011, **11(11)**, 4874-4878 Pop E., Varshney V., Roy A., Thermal properties of graphene: Fundamentals and applications, MRS bulletin, 2012, **37**, 1273-1281 Lei W., Li C., Cole M., Qu K., Ding S., Zhang Y., Warner J., Zhang X., Wang B., Milne W., A graphene -based large area surface-conduction electron emission display, Carbon, 2013, **56**, 255-263 www.cheaptubes.com www.graphenea.com [Global Graphene Battery Market Worth USD 115M Report (BusinessWire, 2016)](http://www.businesswire.com/news/home/20161101006012/en/Global-Graphene-Battery-Market-Worth-USD-115) http://s3.amazonaws.com/academia.edu.documents/41175514/Advanced_carbon_aerogels_for_energy_appl20160114-15050-1liyorj.pdf?AWSAccessKeyId=AKIAJ56TQJRTWSMTNPEA&Expires=1480256913&Signature=21XHgBv83B69AOLeWNHLpXxdIWs%3D&response-content-disposition=inline%3B%20filename%3DAdvanced_carbon_aerogels_for_energy_appl.pdf [KAIST Institute for NanoCentury — Graphene Research Highlight](https://kis.kaist.ac.kr/?mid=KINC_Highlight&highlight_item_srl=40620&catelevel_1_sel=733&catelevel_2_sel=737) http://www.4spepro.org/pdf/004401/004401.pdf [Pushing Graphene (McEuen Group, Cornell University — JVSTB)](http://mceuengroup.lassp.cornell.edu/sites/mceuen/files/publications/JVSTB_Pushing_Graphene.pdf) [Pop E. — Thermal properties of graphene: Fundamentals and applications (arXiv:1301.6181)](https://arxiv.org/abs/1301.6181) [http://www.graphene-info.com](http://www.graphene-info.com/graphene-sensors) [Graphene Sensors Applications (University of Manchester)](http://www.graphene.manchester.ac.uk/explore/the-applications/sensors/) [New Graphene-Based Inks for Printed Electronics (University of Cambridge)](http://www.cam.ac.uk/research/news/new-graphene-based-inks-for-high-speed-manufacturing-of-printed-electronics) ### Source Research-Grade Graphene from Specialists We supply CVD graphene films, graphene oxide, reduced graphene oxide, and graphene nanoplatelets — every material covered in this guide. Consistent quality, CoA with every order, and technical support from a team with 20 years in nanomaterials. [Shop Graphene Oxide →](https://www.cheaptubes.com/product-category/graphene-oxide/)[Shop Graphene Nanoplatelets →](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ## Carbon Nanotube Composites: Types, Properties & Applications Source URL: https://www.cheaptubes.com/resources/carbon-nanotube-composites-types-properties-applications/ Last updated: 2026-04-23 --- ## What Are Carbon Nanotube Composites? Carbon nanotube (CNT) composites are advanced materials formed by dispersing carbon nanotubes — either single-walled (SWCNT) or multi-walled (MWCNT) — into a host matrix such as a polymer, metal, ceramic, or carbon-based system. The resulting material inherits dramatically enhanced mechanical, thermal, and electrical properties compared to the unfilled matrix alone. Even at very low loading levels, typically 0.1–5 wt%, the extraordinary aspect ratio and surface area of CNTs can transform an ordinary matrix into a high-performance engineering material. First demonstrated experimentally in the mid-1990s, CNT composites have grown from a laboratory curiosity into a commercially relevant class of materials used in aerospace structures, automotive components, sporting goods, EMI shielding enclosures, and conductive films. Understanding how to select, disperse, and process CNTs within a chosen matrix is essential to unlocking the full potential of this technology. ## Types of CNT Composites [image: Carbon nanotube composite matrix types comparison: polymer, metal, ceramic, carbon-carbon] ### Polymer Matrix Composites Polymer matrix composites are by far the most widely studied category. Epoxy resins, polyamides, polypropylene, PEEK, and polyurethane have all been combined with both SWCNTs and MWCNTs. The primary challenges are achieving uniform dispersion and strong interfacial adhesion between the CNT surface and the polymer chains. Surface functionalization — covalent attachment of carboxyl (–COOH) or amine (–NH₂) groups — improves wettability and load transfer but can introduce defects that slightly reduce the intrinsic CNT properties. Common processing routes include solution blending (dissolving polymer and dispersing CNTs in solvent before casting or spinning), melt compounding (mixing CNTs into molten thermoplastics via twin-screw extrusion), and in-situ polymerization (growing the polymer in the presence of dispersed nanotubes). Each method offers trade-offs between dispersion quality, scalability, and residual solvent concerns. ### Metal Matrix Composites Aluminum, copper, magnesium, and titanium matrices reinforced with CNTs offer the prospect of lightweight structural components with stiffness and thermal conductivity approaching that of continuous carbon fiber while retaining the ductility of the base metal. Powder metallurgy — mixing CNT powder with metal powder and consolidating by spark plasma sintering (SPS) or hot isostatic pressing — is the most common fabrication route because it avoids the high temperatures that can damage nanotubes or cause unwanted carbide formation. Al–CNT composites with 1–2 wt% MWCNT loading have demonstrated tensile strength improvements of 20–50% over unreinforced aluminum alloys, along with higher wear resistance and lower coefficients of thermal expansion — properties valued in precision electronic packaging and heat sinks for power electronics. ### Ceramic Matrix Composites Brittle ceramics such as alumina, silicon carbide, and hydroxyapatite gain significant toughness when CNTs bridge crack fronts and deflect propagating fractures. CNT-reinforced hydroxyapatite composites are of particular interest in biomedical implant research because the nanotube network can mimic the collagen-mineral hierarchy of natural bone while improving fracture toughness by an order of magnitude over monolithic hydroxyapatite. ### Carbon–Carbon Composites Adding CNTs to conventional carbon fiber-reinforced carbon (C/C) matrices improves the through-thickness thermal conductivity and inter-laminar shear strength — persistent weak points in traditional C/C composites used in aircraft brake discs and rocket nozzles. The synergy between microscale carbon fibers and nanoscale CNTs creates a multi-scale reinforcement architecture that addresses failures at multiple length scales simultaneously. ## Key Mechanical Properties and Improvements Individual SWCNTs exhibit a Young's modulus near 1 TPa and tensile strength of 50–150 GPa — values that far exceed steel on a specific (per-unit-mass) basis. Translating these intrinsic properties into macroscopic composite performance depends on several factors: - Dispersion state: Agglomerated bundles act as stress concentrators and dilute reinforcement efficiency. Achieving individualized, well-dispersed tubes is the central challenge in CNT composite processing. - Aspect ratio: Longer tubes (high aspect ratio) provide more efficient load transfer along their length. MWCNTs with diameters of 10–30 nm and lengths of 5–50 µm are common choices for structural composites. - Alignment: Aligned CNT arrays can improve tensile modulus along the fiber axis by 2–5× compared to randomly oriented composites at the same loading level. Electric field, magnetic field, shear-flow, and fiber-spinning techniques all enable partial alignment. - Interfacial bonding: Covalent functionalization provides strong bonding but reduces CNT perfection. Non-covalent approaches using surfactants or pyrene derivatives preserve tube integrity while still improving wetting. In practice, epoxy-CNT composites at 0.5 wt% loading typically achieve 20–40% improvement in tensile modulus, 15–30% increase in tensile strength, and meaningful gains in fracture toughness (KIc) relative to neat resin. Higher loadings are possible but begin to encounter re-agglomeration and viscosity challenges during processing. [image: Radar chart showing property enhancement of CNT-epoxy composite vs neat epoxy at 0.5 wt% MWCNT] ## Electrical and Thermal Properties CNTs are exceptional electrical conductors along their axis, with individual metallic SWCNTs carrying current densities exceeding 10⁹ A/cm² — roughly 1,000× that of copper. Incorporating just 0.1–1 wt% of well-dispersed CNTs into an insulating polymer can induce a conductor-to-semiconductor or insulator-to-conductor transition, producing an electrically percolating network useful for antistatic packaging, electromagnetic interference (EMI) shielding, and piezoresistive strain sensing. The percolation threshold — the critical CNT concentration where continuous conductive pathways form — depends strongly on aspect ratio. High-aspect-ratio MWCNTs can percolate at loadings as low as 0.05 wt%, far below conventional carbon black or graphite additives. This means composites can be made conductive while adding minimal mass and maintaining optical transparency in thin films. Thermal conductivity improvements in CNT composites are more modest than the intrinsic nanotube values would suggest, largely because phonon scattering at nanotube–matrix interfaces limits heat conduction. Aligned CNT arrays grown directly on substrates (so-called "CNT forests") outperform randomly dispersed composites because they minimize interface density. Nonetheless, 20–100% improvements in through-plane thermal conductivity have been reported for CNT-filled epoxies and thermoplastics, relevant for thermal interface materials in electronics cooling. ## Applications of CNT Composites ### Aerospace and Defense Airframe skins, radomes, and structural panels benefit from CNT composites through weight savings, increased stiffness-to-weight ratio, and built-in electrical conductivity for lightning strike protection — an important certification requirement for composite aircraft. Boeing and Airbus have both publicly explored CNT-enhanced prepreg systems that reduce the need for embedded copper mesh for lightning protection, saving significant weight per aircraft. ### Automotive Body panels, mirror housings, and underhood components made from CNT-modified thermoplastics achieve the conductivity needed for electrostatic spray painting — a critical manufacturing step — at lower loadings than carbon black, enabling thinner walls and lighter parts. CNT composites also find use in fuel system components that require electrostatic dissipation to prevent ignition hazards. ### Sporting Goods Tennis rackets, bicycle frames, golf club shafts, and hockey sticks made with CNT-modified epoxy laminates achieve higher stiffness and vibration damping simultaneously — a combination difficult to achieve with conventional fiber reinforcement alone. CNTs in the resin interlayers between carbon fiber plies act as crack-arresting bridges that reduce delamination under impact. ### Wearable Electronics and Smart Textiles CNT-loaded elastomers and fibers enable stretchable conductors, pressure sensors, and actuators compatible with body-worn devices. The piezoresistive response of CNT networks — where resistance changes predictably with strain — is exploited in gloves that capture hand gesture data, compression bandages that monitor swelling, and e-skin patches for continuous vital sign monitoring. ### Biomedical Functionalized CNTs in biocompatible polymer scaffolds guide nerve cell growth and provide electrical stimulation pathways for neural regeneration research. CNT-reinforced bone cements and hydroxyapatite scaffolds show improved fracture resistance in orthopedic implant applications. Rigorous biocompatibility and toxicology studies remain essential as these applications advance toward clinical use. ## Dispersion Methods and Processing Tips Achieving high-quality CNT dispersion is the most common bottleneck in composite fabrication. The main approaches are: - Ultrasonication: Probe or bath sonication in solvent breaks apart bundles through cavitation. Extended sonication times increase dispersion quality but also shorten CNTs. Typical protocols use 30–60 minutes of probe sonication at controlled temperatures to limit tube damage. - Ball milling: Effective for dry blending of CNTs with metal or ceramic powders but can introduce structural defects. High-energy ball milling with process control agents like stearic acid is standard for metal matrix composite preparation. - Calendering / three-roll milling: Preferred for high-viscosity epoxy systems; provides shear-intensive mixing without solvent and is scalable to production volumes. - Functionalization: Acid treatment (refluxing in H₂SO₄/HNO₃ mixtures) attaches carboxyl and hydroxyl groups that improve wettability in polar matrices. Degree of functionalization is monitored by Raman spectroscopy D/G band ratios — a rising D/G ratio indicates increasing defect density. - Master batch dilution: Pre-dispersing CNTs at high concentration in a compatible carrier resin, then diluting into the final matrix, often produces better results than adding CNTs directly to the full formulation. ## Characterization and Quality Control Standard characterization methods for CNT composites include scanning electron microscopy (SEM) for fracture surface analysis, transmission electron microscopy (TEM) for dispersion quality at the nanoscale, Raman spectroscopy for CNT structural integrity, thermogravimetric analysis (TGA) for CNT content and thermal stability, dynamic mechanical analysis (DMA) for storage modulus and damping, and four-point probe resistivity measurements for electrical percolation studies. Consistent CNT raw material quality is a prerequisite for reproducible composite properties. Key CNT specifications to verify from suppliers include: purity (metal catalyst residue content), outer diameter distribution, length distribution, aspect ratio, surface area (BET), and Raman G/D ratio as an indicator of wall quality. [Multi-walled carbon nanotubes](https://www.cheaptubes.com/product-category/multi-walled-carbon-nanotubes/) and [single-walled carbon nanotubes](https://www.cheaptubes.com/product-category/single-walled-carbon-nanotubes/) from Cheap Tubes are characterized by TEM, Raman, and TGA before shipment, with certificates of analysis available for each lot. ## Selecting CNTs for Your Composite Application The choice between SWCNTs and MWCNTs, and the specific diameter and length within each class, depends on the target property. For maximum electrical conductivity at the lowest loading, SWCNTs or thin MWCNTs (OD 8–15 nm) with very high aspect ratio are preferred. For structural reinforcement in demanding mechanical applications, longer MWCNTs (OD 20–30 nm, length 10–50 µm) provide excellent load transfer at moderate cost. For thermal interface materials requiring high through-plane conductivity, aligned CNT arrays or short, thick MWCNTs with minimum tube–tube junctions are often optimal. Functionalized variants — carboxyl-functionalized, hydroxyl-functionalized, or amine-functionalized MWCNTs — are available for applications where direct covalent bonding to the matrix is required. [Functionalized carbon nanotubes](https://www.cheaptubes.com/product-category/functionalized-carbon-nanotubes/) simplify integration into epoxy, polyurethane, and water-based systems without requiring custom acid treatment steps in-house. ## Research-Grade CNTs for Composite Development Cheap Tubes supplies research- and industrial-grade carbon nanotubes to composite developers, universities, and manufacturers worldwide. Our inventory includes pristine and functionalized SWCNTs and MWCNTs in gram-to-kilogram quantities, with consistent lot-to-lot quality backed by full analytical documentation. Whether you are screening CNT types for a new composite formulation or scaling an established process, we provide the technical datasheets and application support to accelerate your work. [Contact us](https://www.cheaptubes.com/contact-cheap-tubes-inc/) to discuss your composite application requirements or to request samples for initial dispersion trials. **Specialty CNT grades for demanding composites:** Beyond standard straight-tube MWCNTs, specialized architectures like [helical multi-walled carbon nanotubes](/product-category/helical-multi-walled-carbon-nanotubes/) deliver unique mechanical interlocking and electromagnetic response for advanced composite designs. ## Related Reading Go deeper on related topics: - History and Production Methods of Carbon Nanotubes — how CNTs are actually synthesized at scale — context for why certain composite grades perform the way they do. - Functionalization of Graphene Nanoplatelets in Epoxy Composites — peer-reviewed mechanical data on surface chemistry and filler-matrix bonding. - Graphene Sensors — how graphene and CNTs compare in strain and gas sensing applications. - Fullerenes: Structure, Properties, and Applications — sp² carbon allotrope family context; useful background for CNT composite researchers exploring fullerene-reinforced systems. --- ## Graphene Batteries: Technology, Chemistry & Commercial Progress Source URL: https://www.cheaptubes.com/resources/graphene-batteries-technology-chemistry-commercial-progress/ Last updated: 2026-04-23 --- ## What Are Graphene Batteries? Graphene batteries are energy storage devices that incorporate graphene — a single-atom-thick sheet of sp²-bonded carbon — into one or both electrodes to enhance electrochemical performance. Rather than replacing conventional lithium-ion chemistry outright, most graphene battery technologies use graphene or its derivatives (graphene oxide, reduced graphene oxide, graphene nanoplatelets) as additives, coatings, or structural components within existing electrode architectures. The result is improved rate capability, cycle life, energy density, and thermal management compared to conventional carbon-only electrodes. The term "graphene battery" is used loosely in both research literature and marketing materials. In rigorous usage it encompasses: lithium-ion cells with graphene-modified anodes or cathodes, lithium-sulfur cells with graphene sulfur-host frameworks, sodium-ion cells using hard carbon–graphene composite anodes, lithium–air cells with graphene air electrodes, and hybrid supercapacitor–battery devices exploiting the double-layer capacitance of graphene alongside faradaic battery reactions. ## Why Graphene Improves Battery Electrodes The performance advantages of graphene in battery electrodes stem directly from its exceptional physical properties: - Electrical conductivity: Graphene's in-plane electron mobility (~200,000 cm²/V·s for pristine monolayer) creates a highly conductive network within electrode films, reducing ohmic losses during fast charge and discharge. - High surface area: Theoretical surface area of ~2,630 m²/g for single-layer graphene provides abundant active sites for lithium ion intercalation and double-layer charge storage. - Mechanical flexibility: Graphene's tensile strength (~130 GPa) and elastic modulus (~1 TPa) allow it to accommodate volume changes during cycling without fracturing — a critical advantage for silicon and sulfur electrodes that expand 300–400% during lithiation. - Chemical versatility: Functional groups on graphene oxide (–OH, –COOH, epoxide) can anchor sulfur, metal oxides, and other active materials through covalent or electrostatic interactions, preventing aggregation and loss of active material. - Thermal conductivity: High in-plane thermal conductivity (~5,000 W/m·K for suspended single-layer) helps distribute heat within electrode stacks, reducing thermal gradients that accelerate degradation. [image: Ragone plot comparing energy density vs power density for graphene batteries, Li-S, conventional Li-ion, and supercapacitors] ## Graphene in Lithium-Ion Battery Anodes The anode of a conventional lithium-ion battery uses graphite, which stores lithium at a theoretical capacity of 372 mAh/g. Graphene-based anodes have demonstrated capacities of 700–1,100 mAh/g in research settings, though practical reversible capacities in full cells are typically 400–600 mAh/g due to solid-electrolyte interface (SEI) formation on high-surface-area graphene consuming lithium irreversibly on first charge. The most commercially significant graphene anode application is not replacing graphite but enhancing silicon-graphite composites. Silicon offers ~3,580 mAh/g theoretical capacity but experiences catastrophic volume expansion (~300%) during lithiation, causing pulverization and rapid capacity fade. Wrapping silicon nanoparticles in graphene sheets or embedding them in reduced graphene oxide (rGO) scaffolds creates a flexible buffer that accommodates expansion while maintaining electrical contact throughout thousands of cycles. Several major cell manufacturers, including Panasonic, Samsung SDI, and emerging startups, have incorporated graphene-silicon composite anodes into next-generation 21700 and 46xx cylindrical cells. ## Graphene in Lithium-Ion Battery Cathodes Cathode materials including LFP (LiFePO₄), NMC (LiNiMnCoO₂), and NCA (LiNiCoAlO₂) have inherently low electronic conductivity that limits rate capability at high charge/discharge currents. Coating these particles with graphene nanoplatelets or conductive carbon derived from graphene oxide creates percolating conductive networks that dramatically reduce internal resistance and enable faster charge rates without sacrificing energy density. LFP–graphene composite cathodes have become particularly important for EV and grid storage applications because LFP is lower-cost, thermally safer, and longer-lived than NMC, but was historically limited by poor rate performance. Graphene-coated LFP cathodes have enabled C-rates of 10C and above — meaning full charge in 6 minutes — while maintaining 90%+ capacity after 2,000+ cycles, making them competitive with NMC at fast-charge applications. ## Graphene in Lithium–Sulfur Batteries Lithium–sulfur (Li-S) batteries offer a theoretical energy density of ~2,600 Wh/kg, roughly 5× higher than current lithium-ion technology, making them a leading candidate for long-range aviation and grid storage. However, the polysulfide shuttle — where soluble intermediate discharge products (Li₂S₄ to Li₂S₈) dissolve into the electrolyte and migrate to the lithium anode — causes rapid self-discharge and capacity fade that has historically blocked commercialization. Graphene and graphene oxide play several roles in addressing these challenges. Three-dimensional rGO aerogels serve as conductive sulfur hosts that physically confine polysulfides within the cathode structure. Nitrogen-doped graphene provides chemical anchoring sites (pyridinic N, pyrrolic N) that bind polysulfide anions through Lewis acid–base interactions, reducing dissolution. Graphene interlayers placed between the cathode and separator act as polysulfide barriers while providing additional conductive surface area. These approaches have extended Li-S cycle life from tens of cycles to several hundred, bringing practical application closer. ## Graphene in Sodium-Ion Batteries Sodium-ion batteries (SIBs) are emerging as a cost-competitive alternative to lithium-ion for stationary grid storage because sodium is far more abundant and geographically distributed than lithium. Sodium ions (ionic radius 1.02 Å) are too large to intercalate efficiently into conventional graphite, so SIBs use hard carbon — disordered, turbostratic carbon — as the anode material. Graphene nanoplatelets blended with hard carbon precursors, or reduced graphene oxide as a co-anode component, increase the interlayer spacing and defect density that accommodates sodium ions, improving both capacity and rate capability. CATL and HiNa Battery Technology have both announced sodium-ion cells for EV and grid applications. As SIB anodes are optimized, graphene-derived carbons are expected to play an increasing role in achieving the 300+ Wh/kg targets that would make sodium-ion cells competitive with entry-level lithium-ion for mobility applications. ## Graphene Supercapacitors and Hybrid Devices Electrochemical double-layer capacitors (EDLCs, supercapacitors) store charge electrostatically at the electrode–electrolyte interface rather than through faradaic reactions, enabling extremely high power density (10–100 kW/kg) and millions of cycles with no chemical degradation. Activated carbon is the standard electrode material, but graphene's higher theoretical surface area and better conductivity have driven intense research into graphene-based supercapacitors. Practically, graphene sheets tend to restack during electrode fabrication, reducing accessible surface area back toward graphite levels. Strategies to maintain high surface area include: introducing spacer molecules or nanoparticles between layers, crumpling graphene sheets into a morphology that resists restacking, templating graphene onto 3D porous scaffolds, and using laser-scribed or microwave-exfoliated graphene that retains a porous structure. Graphene-based supercapacitors have achieved gravimetric capacitances of 150–300 F/g and energy densities of 70–85 Wh/kg — comparable to lead-acid batteries — while retaining the power density advantage of conventional supercapacitors. Hybrid lithium-ion capacitors (LICs) combine a battery-type anode (often graphene-enhanced hard carbon or pre-lithiated graphite) with a capacitor-type cathode (activated carbon or graphene), targeting the middle ground between batteries and supercapacitors for applications like regenerative braking, UPS systems, and industrial power buffers. ## Thermal Management in Battery Packs Beyond electrode chemistry, graphene's thermal conductivity makes it valuable as a battery pack thermal management material. Graphene-enhanced thermal interface materials (TIMs) placed between cells and cooling plates in EV battery packs reduce junction temperatures under fast charging, extending cycle life and enabling higher sustained charge rates. Graphene foils and papers produced by compressing graphene nanoplatelets achieve in-plane thermal conductivities of 700–1,500 W/m·K — several times higher than copper foil — at a fraction of the weight. [Graphene nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) with high aspect ratio and platelet diameter of 5–25 µm are well suited for thermal management applications, where heat must be spread laterally through the electrode stack or TIM layer. Products with surface areas of 120–750 m²/g cover the range from structural conductive additives to high-surface-area supercapacitor electrodes. ## Current Commercial Landscape As of 2025, fully graphene-based batteries remain primarily a research and development technology, while graphene as an additive or performance enhancer in conventional lithium-ion and emerging chemistries has entered commercial production. Notable developments include: - Real Graphene (Canada): Markets USB-C power banks using graphene-enhanced lithium polymer cells, claiming 20-minute full charge and 1,500-cycle life for consumer electronics. - Grabat (Spain): Demonstrated graphene polymer battery cells targeting 1,000 Wh/kg, though independent verification of claimed performance in production cells has been limited. - Lyten (USA): Has raised substantial venture funding for its Li-S graphene battery platform, targeting EV applications with cells demonstrating 900+ Wh/kg at the material level. - Samsung SDI, CATL, Panasonic: Incorporate graphene-silicon composite anodes and graphene conductive additives in commercial 21700 cells and next-generation prismatic formats without marketing them as "graphene batteries." [image: Bar chart comparing cycle life and capacity of graphene-silicon, graphene-LFP, and Li-S graphene battery electrodes] ## Related Reading Go deeper on related topics: - Functionalization of Graphene Nanoplatelets — how surface chemistry affects graphene-polymer bonding — relevant to electrode binder interactions. - Essential Ingredients for Nanowire Growth — engineering context for adjacent nanomaterial systems — useful for silicon-anode and Li-S development. - Most Sensitive Carbon Nanotube Photodetector — graphene and CNT device engineering — same materials-science mindset that drives electrode design. - Fullerenes: Structure, Properties, and Applications — benchmark electron acceptors for OPV and related sp² carbon material science relevant to battery electrode research. ## Graphene Materials for Battery Research Researchers developing graphene battery technologies require materials with well-defined and consistent properties. Key specifications include: number of layers (monolayer vs. few-layer vs. graphene nanoplatelets), lateral platelet size (affects aspect ratio and restacking tendency), oxygen content (C:O ratio for graphene oxide and rGO grades), surface area (BET, m²/g), and electrical conductivity (S/m for rGO and GNP powders). Cheap Tubes supplies a complete range of graphene materials for battery electrode research, including [graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) for slurry-based electrode fabrication, [reduced graphene oxide](/product-category/graphene-oxide/) for conductive scaffolds and rGO aerogels, and [graphene nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) for cathode conductive additives and thermal management films. All products are supplied with full analytical documentation including TEM, Raman, TGA, and BET data to support reproducible research. ## Key Metrics for Evaluating Graphene Battery Claims The graphene battery space attracts significant marketing hyperbole. When evaluating claims from suppliers, startups, or published papers, focus on specific metrics to distinguish genuine advances from promotional noise. Gravimetric energy density (Wh/kg) and volumetric energy density (Wh/L) should be reported at the full cell level, not just the active material level, since packaging, current collectors, separator, and electrolyte dilute material-level numbers by 30–60%. Cycle life should be specified at a defined capacity retention threshold — for example, 80% capacity after N cycles at a defined C-rate under defined temperature conditions. First-cycle coulombic efficiency matters for graphene anodes: high-surface-area graphene materials often have low first-cycle efficiency due to SEI formation, requiring pre-lithiation or excess cathode capacity to compensate. Rate capability curves — capacity plotted versus C-rate from C/10 through 10C — reveal how much energy is accessible at real-world charge rates versus only at slow laboratory rates. Thermal performance data, including heat generation per cycle at high C-rates and maximum sustained operating temperature, become increasingly important as fast-charging enters the mainstream for EVs and portable electronics. Asking for independent third-party validation or peer-reviewed publication data is a reasonable standard for any material claiming performance well beyond incumbent technologies. Cross-referencing supplier data sheets against published electrochemical literature allows researchers to set realistic expectations before committing to a specific graphene grade for electrode development. [Contact our technical team](https://www.cheaptubes.com/contact-cheap-tubes-inc/) to identify the right graphene grade for your battery chemistry, or to request samples for preliminary electrode trials. --- ## MXene Materials: Properties, Applications & Where to Buy Source URL: https://www.cheaptubes.com/resources/mxene-materials-properties-applications/ Last updated: 2026-04-23 --- MXene materials represent one of the most significant discoveries in two-dimensional materials science since graphene. First synthesized in 2011 at Drexel University, MXenes have rapidly emerged as a leading material for energy storage, electromagnetic shielding, sensing, and flexible electronics — combining electrical conductivity, hydrophilicity, and solution processability in a single material family that no prior 2D material could match. ## What Are MXene Materials? MXenes are a family of two-dimensional transition metal carbides, nitrides, and carbonitrides produced by selectively etching the "A" layer from MAX phase precursors. MAX phases are layered ternary carbides or nitrides with the general formula Mn+1AXn, where M is an early transition metal (titanium, vanadium, niobium, molybdenum), A is an A-group element (typically aluminium or silicon), and X is carbon or nitrogen. When the A layer is removed — most commonly using hydrofluoric acid or fluoride salt etchants — the result is a stack of MX layers with surface terminations of –OH, –F, and –O groups. These surface groups are critical: they make MXene surfaces hydrophilic and negatively charged, allowing MXene flakes to disperse readily in water without surfactants, form stable colloidal solutions, and be processed into films, coatings, and composites using standard solution-processing techniques. The most widely studied MXene is Ti₃C₂Tₓ (titanium carbide MXene), derived from Ti₃AlC₂ MAX phase. It combines metallic electrical conductivity (~6,000 S/cm in thin films, exceeding most other 2D materials), high volumetric capacitance, and solution processability that makes it far easier to work with than graphene or transition metal dichalcogenides. [image: Scientific diagram of MXene Ti₃C₂Tₓ layered structure showing titanium carbide sheets separated by surface functional groups (–OH, –O, –F) and ~1 nm interlayer spacing] ## Key Properties of Ti₃C₂Tₓ MXene The properties that make Ti₃C₂Tₓ MXene exceptional for device applications stem from its unique combination of metallic conduction in a hydrophilic, solution-processable 2D material: - Electrical conductivity — thin films of Ti₃C₂Tₓ reach conductivities of 2,000–6,000 S/cm, comparable to metallic thin films and orders of magnitude above graphene oxide or reduced graphene oxide films of similar thickness - Volumetric capacitance — Ti₃C₂Tₓ electrodes demonstrate volumetric capacitances of 900–1,500 F/cm³, among the highest reported for any electrode material, making it ideal for compact energy storage devices - Electromagnetic shielding — a 45 µm thick Ti₃C₂Tₓ film achieves electromagnetic interference shielding effectiveness of over 90 dB — exceeding copper foil of the same thickness — due to the combination of high conductivity and multiple internal reflection at the 2D flake interfaces - Solution processability — MXene flakes disperse in water at concentrations up to 30 mg/mL without surfactants, enabling spray coating, spin coating, vacuum filtration, and inkjet printing without organic solvents - Mechanical flexibility — free-standing MXene films (MXene paper) can be bent and flexed without loss of electrical properties, enabling integration into flexible and wearable devices - Tuneable surface chemistry — the ratio of –F, –OH, and =O surface terminations can be controlled through synthesis conditions and post-processing, modifying electrochemical behaviour and interlayer spacing ## MXene for Energy Storage Energy storage represents the most extensively studied application for MXene materials. Ti₃C₂Tₓ functions as an exceptional pseudocapacitive electrode material — charge storage occurs not only through double-layer capacitance at the surface but through fast, reversible redox reactions involving the surface termination groups and titanium oxidation states. This pseudocapacitive mechanism gives volumetric capacitances far exceeding conventional activated carbon electrodes while maintaining the fast charge/discharge kinetics of a supercapacitor rather than the slow diffusion-limited behaviour of a battery. MXene electrodes have been demonstrated in both aqueous and organic electrolyte supercapacitors, as well as in hybrid devices combining MXene pseudocapacitance with battery-type electrode materials. In lithium-ion batteries, Ti₃C₂Tₓ has been explored as an anode material, delivering capacities around 400 mAh/g with excellent rate capability. For sodium-ion and potassium-ion batteries — where graphite anodes perform poorly — MXene anodes show promise due to the larger interlayer spacing that accommodates the bigger Na⁺ and K⁺ ions. Composite electrodes combining MXene with [graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) or reduced graphene oxide address MXene's tendency to restack — the graphene sheets act as spacers between MXene flakes, preserving the accessible surface area and maintaining high capacitance even after repeated cycling. ## MXene for Electromagnetic Interference Shielding The electromagnetic shielding performance of Ti₃C₂Tₓ MXene has generated significant commercial interest. Traditional EMI shielding materials — copper, aluminium, carbon fibre composites — are heavy, rigid, or require high loadings in polymer matrices. MXene films achieve exceptional shielding at thicknesses and weights that no prior material could match. The shielding mechanism in MXene differs from purely absorptive materials: the primary mechanism is reflection from the highly conductive surface, supplemented by multiple internal reflections as the electromagnetic wave passes through the layered MXene structure. This makes MXene effective across a broad frequency range from kHz to GHz. For flexible electronics and wearable devices where weight and conformability matter, MXene coatings applied by spray or dip coating can impart EMI shielding to fabric, polymer films, and foam substrates at loadings well below those required for carbon nanotube or graphene-based coatings to achieve comparable shielding effectiveness. ## MXene for Sensing Applications The sensitivity of MXene's electrical properties to surface interactions makes it a natural sensing material. Ti₃C₂Tₓ has been demonstrated in gas sensors, pressure sensors, strain sensors, biosensors, and temperature sensors — often outperforming graphene-based sensors in specific applications due to the abundance of active surface sites from the termination groups. For gas sensing, the surface termination groups interact selectively with different analyte molecules, causing measurable resistance changes. MXene gas sensors have demonstrated sub-ppm detection limits for volatile organic compounds, ammonia, and nitrogen dioxide at room temperature — without the elevated operating temperatures required by metal oxide sensors. For pressure and strain sensing, the contact resistance between MXene flakes in a film changes predictably under mechanical deformation, giving gauge factors competitive with the best carbon nanotube and graphene strain sensors. The hydrophilic surface also enables direct integration with biological systems for wearable health monitoring without the biocompatibility concerns of hydrophobic carbon nanomaterials. ## MXene Ink and Coating Formulations One of MXene's most practically useful properties is the ease with which it forms stable aqueous inks suitable for printed electronics. Unlike carbon nanotube inks (which require sonication and surfactants) or graphene inks (which require organic solvents for high-quality dispersions), Ti₃C₂Tₓ disperses spontaneously in water to form stable, highly conductive inks that can be printed by inkjet, screen printing, and aerosol jet methods. Printed MXene antennas, electrodes, and conductive traces on flexible substrates have been demonstrated with conductivities sufficient for practical device applications — opening opportunities in printed sensors, RFID tags, flexible displays, and wearable electronics that conventional printing-compatible conductive inks (silver, carbon black) either cannot match for conductivity or cannot match for cost. [image: Horizontal bar chart showing MXene research publication distribution by application: energy storage 38%, EMI shielding 27%, sensors 18%, photocatalysis 10%, conductive inks 7%] ## Related Reading Go deeper on related topics: - Essential Ingredients for Nanowire Growth — a review of what it takes to grow well-defined nanowires — relevant to MXene precursors and 2D-material synthesis. - Most Sensitive Carbon Nanotube Photodetector — CNT-based photodetector research that shares sensing physics with MXene photodetector work. - Graphene Biosensors — 2D-material biosensing overview — MXenes are increasingly paired with graphene in sensing platforms. ## Buy MXene Materials for Research Cheap Tubes supplies [Ti₃C₂Tₓ MXene](/product-category/mxene/) in both powder and aqueous dispersion form for research applications. Our MXene is characterised by XRD for phase purity, SEM for flake morphology, and conductivity measurement of pressed pellets for each production lot. Certificate of analysis included with every order. For groups working on MXene composite electrodes, EMI shielding films, or printed electronics, we can provide technical guidance on dispersion preparation, film formation, and integration with complementary materials including [graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) and [graphene nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/). [Contact our team](https://www.cheaptubes.com/contact-cheap-tubes-inc/) for bulk pricing and custom specifications. --- ## Solar Applications of Graphene Source URL: https://www.cheaptubes.com/solar-applications-of-graphene/ Last updated: 2026-04-23 --- [Download our Solar Applications of Graphene PDF](https://www.cheaptubes.com/wp-content/uploads/2017/06/Solar-Applications-of-Graphene-PDF.pdf) **Quick Summary: Graphene in Solar Cells** - 20% efficiency gain potential — Graphene reduces solar reflectance by up to 20% vs. conventional electrode materials - 97.7% optical transparency — Single-layer graphene transmits nearly all visible light, ideal for transparent electrodes - Versatile across cell types — Effective in silicon, polymer, dye-sensitized, perovskite, quantum dot, and organic solar cells - Doping tunes performance — P-type (boron) and n-type (phosphorus) doping adjust graphene's bandgap for optimal photovoltaic behavior - Replaces ITO — Graphene is a flexible, earth-abundant alternative to brittle indium tin oxide in transparent conductive electrodes [image: graphene-solar-power-station] As our dependence upon renewable energy becomes more apparent, the need for efficient solar cells becomes more crucial, especially when they are one of the easiest and cheapest ways to generate clean energy. In general, solar cells are not that efficient. However, recent advances in graphene- based solar cells have seen the reflectance of solar rays reduced by 20%, which provides a potential efficiency increase up to 20%. There are currently many different variations of graphene-based solar cells being researched today. This guide gives a comprehensive overview into the different types that are being investigated by academic and corporate researchers around the world. ## Principles of Graphene Solar Cells The basic principle of a graphene-based solar cell is essentially not that different from current inorganic/silicon solar cells being produced today, with the exception that some of the materials currently in use are replaced with graphene derivatives. As with any device or material, there are parameters that can be improved to increase operational efficiency. Graphene excels in tune-ability and adaptability. For graphene-based solar cells, the two standout parameters that can potentially change the nature of the device are the number of graphene layers in the device (or in the individual components within a device) and the effects of doping a graphene-based material. [image: Graphene-Silicon-Solar-Panels] ## Effects of Graphene Layers in Solar Cells The relationship between optical transparency, sheet resistance, and the number of layers can be characterized by a proportional decrease in both the optical transparency and the sheet resistance, with an increasing number of graphene layers. A single layer of graphene shows an optical transparency of 97.7%. A 3-layered graphene stack exhibits around 90.8% optical transparency and the addition of each layer corresponds to a 2.3% decrease in optical transparency. A single sheet of graphene produces a sheet resistance of 2.1 kΩsq-1 and 350 Ωsq-1, while retaining 90% optical transparency. The quenching effect of multiple graphene layers can be up to 11% greater than [monolayer graphene](https://www.cheaptubes.com/product-category/cvd-graphene-films/), due to a higher hole accepting density. ## Effects of Doped Graphene in Solar Cells The doping of heteroatoms onto a sheet of graphene can significantly alter the chemical, physical, electronic and photonic properties of the sheet and is a common approach in many solar cells. There are two main types of doping- p-type and n-type. P-type doping utilizes trivalent atoms, such as boron, which extracts an electron off the graphene sheet and creates a hole, a process known as hole doping, where the hole is created in the valence band of the graphene sheet. Whereas, n-type doping involves pentavalent atoms, such as phosphorous, and is an electron donating doping approach that facilitates a free electron from the pentavalent atom onto the graphene sheet. The free electron in this instance is facilitated in the conductance band of the graphene sheet. Doping a graphene sheet can occur through various methods, including through solid, liquid and gaseous phase chemical doping, ball milling, thermal annealing, in-situ doping during chemical vapor deposition (CVD) methods and plasma treatment, to name a few. The effect of doping varies depending on both the type of graphene derivative used and the doping process. Regardless of which of these parameters (or both) are utilized in the doping process, the general result is improved efficiency of the solar cell. [image: Graphene silicon solar cell: graphene transparent electrode on silicon for high-efficiency hybrid photovoltaics] ## Graphene-Silicon Solar Cells [image: Graphene organic photovoltaic OPV device structure showing glass graphene anode PEDOT bulk heterojunction ETL and metal back electrode] Various allotropes of carbon have been implemented into solar cells to reduce the cost, allowing them to be more widely used. Other allotropes of carbon, have not been successful due to the inability to tune the electronic properties and the thickness of the layers. Graphene based films for solar cells can be produced with a predetermined thickness and complete coverage. It also allows the properties to be tuned, dependent upon the doping mixture used. Graphene has now been implemented into various junctions in graphene-silicon solar cells, including p-type heterojunctions, n-type heterojunctions and Schottky junctions. Graphene-silicon solar cells are being researched however pure silicon cells performance is still superior. The tuneability of graphene is promising for hybrid solar cells. While it is not at the same level yet, advancements are being made and it is just a matter of time until their efficiency surpasses pure silicon cells. To date, n-type heterojunctions can generate a 0.55- 0.57 internal voltage to help facilitate electron-hole separation. Schottky junctions have only showed a power conversion efficiency (PCE) of 1.5%, but the fill factor at present has only reached 56%, so theoretically, the efficiency can be vastly improved upon. Doping the graphene layers with gold particles has found to increase the efficiency by up to 40%. [image: Flexible graphene solar panel: lightweight transparent graphene electrode on flexible plastic substrate] ## Graphene-Polymer Solar Cells [image: Band diagram of graphene GaAs Schottky junction showing Fermi levels conduction band valence band bending and Schottky barrier height] A highly researched area of graphene incorporation is in polymer-based solar cells. Polymeric materials offer many advantages over inorganic-based materials due to their tuneability, low-cost and simple fabrication processes. Graphene has shown great potential in transparent electrodes as a replacement for indium tin oxide (ITO) in polymer-based solar cells. The graphene in the electrode becomes an organic-inorganic hybrid material after it undergoes coating, layering, reduction and temperature annealing. The hybrid material has a better energetic relationship, as the fermi-level of the graphene and the semi- conducting layer are closer together for an efficient charge injection. Graphene-polymer transparent electrodes also possess a high work function and conductivity, but it does have a limit of 65% light transmittance. In addition to reducing the graphene into hybrids, CVD-produced graphene can also be used as transparent electrodes. CVD-graphene is ozone treated, which produces carbonyl and hydroxyl functional groups on the surface of the graphene. The oxygen based functional groups improves the open circuit voltage, but conductivity is reduced due to the sp2 hybridized covalent network being disrupted by sp3 bonds around the functionalized carbons. Non-covalent functionalized CVD-grown graphene shows a good conductivity and can have up to 0.55 V open circuit voltage, a fill factor of 55% and a PCE of 1.71%. The flexibility of graphene allows the solar cell to bend up to 78° more than pure ITO electrodes. Electron transporter and acceptor based graphene-polymer solar cells rely on a high electron affinity to dissociate the electron-hole pairs into separate charges. Unlike other materials, graphene gives and effective separation when mixed with conjugated polymers. The large surface area of graphene allows for a continuous pathway and multiple donor/acceptor sites for efficient electron transfer. This type of solar cell has produced a PCE of 1.1%. A hole transport layer is required in many solar cells to stop current leaking and charge recombination. Graphene can be mixed with polymeric material to produce a material with a band gap of up to 3.6 V which prohibits electron migration from the cathode to the anode. A 2nm [graphene film](https://www.cheaptubes.com/product-category/cvd-graphene-films/) is known to provide the best results as the thick film prevents the transmittance of electrons and increases electrical resistance. The highest PCE obtained has been 9 %, which is comparable, if not greater, than other materials used as hole transport layers. [image: Dye-sensitized solar cell (DSSC) structure with graphene electrode replacing ITO] ## Dye Sensitized Solar Cells (DSSC’s) [image: Dual-axis graph showing graphene transparent electrode transmittance percent and sheet resistance ohms per square versus number of graphene layers compared to ITO] DSSC’s are different when compared to other types of solar cells. They contain a semi-conducting material (e.g. TiO2) with a photo-sensitive dye as the anode coupled with a pure metal cathode (e.g. Platinum) and an electrolyte solution. Graphene has many favourable properties that can increase the loading efficiency of the dye molecules, increase the interfacial area and improve the conductivity of the electrons to compete against the effects of charge recombination. Balancing the ratio of TiO2 and graphene is crucial to achieving an efficient system. The valence electrons from graphene become excited into the TiO2 conduction band via the graphene-TiO2 interface, which efficiently separates the electrons and the holes. So, enough graphene is required (roughly 1%) to facilitate this separation, but the introduction of higher graphene concentrations into the matrix causes the transmittance to be reduced. The incorporation of graphene into DSSC’s improves the light scattering at the photoanode, efficiently disperses the dye molecules and provides an efficiency that is 39% greater than pure TiO2 electrodes. [image: Quantum-Dot-Solar-Cells] ## Graphene/Quantum Dot (QD) Solar Cells Both graphene and carbon nanotubes have been hybridized with quantum dots to make functioning solar cells. Of the two carbon allotropes, graphene hybridized quantum dots have shown the most potential. Produced by electrophoretic and chemical bath deposition on ITO, a layered structure of both graphene layers and CdS quantum dots can be produced. The optimal layering structure consist of eight repeating graphene-CdS bilayers. This graphene-CdS configuration can produce and efficiency of up to 16%, which out performs carbon nanotubes-CdS by 7%, and 11% for other carbon allotropes. This is attributed to graphene producing a better scaffold to incorporate the quantum dots, the layered structure provides a fast electron transfer from the QD to the graphene while suppressing the recombination of charges. ## Graphene-Tandem Solar Cells Tandem solar cells, otherwise known as multi-junction solar cells, are composed of two or more sub- cells that are stacked together in either a series or parallel configuration. It has been predicted that a single solar cell can theoretically produce up to 40% solar energy conversion efficiency, but tandem solar cells have the potential to reach up to 86% efficiency. The PCE of many solar cells has been enhanced to date by employing tandem arrangements. The use of low band-polymer hybrid solar cells, commonly using ITO and other carbon derivatives, has been well studied, but graphene-based tandem solar cells are still a relatively new field. There has, however, been some promising developments using [graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/). Graphene tandem solar cells have not yet reached the heights of their non-graphene counterparts, but as a relatively new area they show great potential, especially as non-graphene tandem solar cells show relatively high PCEs. One such development is that of a [graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) and polymer tandem solar cells that consist of 2 sub-cells. The cells consist of a bilayer of Cs-neutralized [graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) and pure graphene oxide connected by a charge recombinant layer of MoO3 and aluminium. Such cells have been found to produce a PCE between 2.92% and 3.91%, depending on the polymer blend used and the thickness of the different components within the cell. The open circuit voltage of the cell can vary between 1.23 V and 1.69 V, but is dependent on the resistance of the interconnecting layer between the graphene oxide sheets, which is a function of the thickness of the layer. Another tandem cell that utilizes graphene also incorporates single-walled carbon nanotubes. Combinations of these materials have also been used as the hole transport and interconnecting layers for ITO-based sub-cells. The thin film composed of these two carbon allotropes have been used in both regular and inverted solar cells, and the associated solar cells exhibit PCEs of up to 3.50% and 2.90%, respectively. The resulting solar cell possess a higher PCE than solar cells that contain the same sub-cells but lack the graphene connecting layers. Even though in this application they are not directly involved in the sub-cells, the presence of graphene in the device increases its overall efficiency. ## Graphene-Perovskite Solar Cells (PSCs) [image: Graphene perovskite solar cell PSC layer structure showing transparent anode TiO2 ETL MAPbI3 absorber HTL and back contact] Perovskite solar cells (PSCs) have made great strides over the last few years due to their interesting bandgap and absorption properties that produce high PCEs. Perovskite solar cells have a standard structure, including the type of materials that are used, so the substitution of one material for another is a relatively simple process that leads to highly tuneable solar cell devices. Nanocomposites composed of anatase-TiO2 and graphene nanoflakes have shown promise with a PCE up to 15.6%. The best results in these solar cells can be achieved when the nanocomposite is utilized as an n-type electron collection layer. The graphene is present as a monolayer and is only present as 0.6 wt% of the whole cell. Any amount above this drops the efficiency and is dependent upon a thin collecting layer. These perovskite solar cells can also be produced by low temperature sintering methods. These cells also possess short circuit and open circuit values of 12-21.9 mAcm-2 and 1.05 V, respectively. When paired with an efficient light absorber, graphene oxide can be used as a hole conductor for inverted solar cells. The fabrication of this class of PSC is more complex in its synthesis, but provides a PCE between 9.26% and 11%, which is up to 7% greater than similar solar cells without the graphene oxide layer. Thinner layers of graphene oxide (2nm) can produce higher efficiencies. The average short and open circuit values in these solar cells are around 15.58 mAcm-2 and 0.99 V. Similar solar cells to the previous example have been created, but by using [reduced graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) as a hole transport layer, with a light absorber material. These solar cells only reach a PCE maximum of 9.14%, but are much more stable and can retain 62% of their initial PCE after 140 hours of constant sun exposure. Thus out performing many other solar cells that can deteriorate significantly after 120 hours. The higher stability is attributed to the increased resistance that [reduced graphene oxide](https://www.cheaptubes.com/product-category/graphene-oxide/) possess against oxygen and moisture compared to other graphene derivatives. One application of graphene oxide is to functionalize it with amphiphilic moieties to promote interface wettability on the surface of a perovskite solar cell. The modification of graphene oxide can reduce the contact angle of hole transporting layer solutions to 0°. The carbon-carbon bonds in the graphene sheet absorb the hole transport layer molecules via p-p interactions and improve the both the interfacial interactions within the solar cell which leads to an improved performance. The functionalized graphene oxide can be doubled up as a buffer layer in PSCs and the dual-purpose graphene sheets can not only increase the short and open circuit potentials, but also increase the PCE of a PSC device by up to 45%. The graphene derrivative graphyne can be used in PSCs to achieve high results. Graphyne is a 2D material similar to graphene, but unlike graphene’s structure of a regular hexagonal sp2 array, graphyne possess a mixture of sp and sp2 hybridised carbons and can be thought of as a lattice of phenyl rings connected by acetylene bonds, which arrange themselves as irregular hexagons. The incorporation of graphyne into hybrid electrodes, in an inverted solar cell, can achieve PCEs up to 14.8%- much higher than non-graphyne solar cells of a similar composition. ## Graphene-Organic Solar Cells While the main focus around solar cells generally tends to involve the different inorganic components, the organic components of the solar cell also play a major role. Organic and inorganic components in a solar cell have advantages and disadvantages, but the optimization of the organic components can produce a more efficient solar cell. Components that might traditionally be inorganic in nature are now being replaced with inorganic- organic hybrid materials that offer greater physical properties, solution-processability, cost-effective production, a large surface area, and are much lighter in nature. One concern with many solar cells is the environmental stability, but organic molecules can provide stability against temperature, moisture and chemical degradation in solar cells, even when present as a hybrid material. The combination of organic and inorganic components generally produces higher stabilities and efficiencies than their pure predecessors. Aside from the two electrodes, traditional organic solar cells contain an active PEDOT:PSS layer and a donor-acceptor blend layer- commonly composed of P3HT or fullerenes (or both). In recent years, the active PEDOT:PSS layer has been replaced by graphene derivatives and are generally used as hole-transport layers in organic solar cells. These components, while not specifically a class of their own, cover a wide range of solar cell applications nowadays, including in many heterojunction solar cells. ## Graphene Bulk-Heterojunction Solar Cells Graphene’s high electronic conductivity, transparency and flexibility make them useful in heterojunction solar cells, where they can be employed in many different ways including electrodes (both anodes and cathodes), acceptor layers, donor layers, buffer layers and active layers. The multijunction within the solar cell relies heavily on graphene’s specific tuneable parameters, including the thickness, thermal annealing temperature, the concentration of doping on the sheet and its photovoltaic performance. Graphene-heterojunction solar cells are by far the most widely studied and used graphene-based solar cell. There are many variations of heterojunction solar cells and how graphene derivatives can be incorporated into them, including as transparent electrode, photoactive layers and Gallium Arsenide (GaAs) solar cells. As such, graphene heterojunction solar cells cannot be generalized as a single class of solar cells. ## Graphene Transparent Electrodes [image: Energy level diagram showing graphene quantum dot photoactive layer cascade charge transfer mechanism from donor through graphene QD to acceptor] Graphene can easily be incorporated into certain layers. Coupled with its excellent electrical, optical, mechanical, and thermal properties, this has allowed graphene to be studied as transparent electrodes in solar cells. We’ve explored a few of the different molecules employed in composite graphene transparent electrodes, but there are many others currently being researched. Prior to graphene being employed as a transparent electrode, ITO was the most commonly used material because of its high optical transparency. However, ITO is not cost effective, is brittle, and lacks mechanical flexibility. Graphene exhibits a high optical transparency 90-100% and a low sheet resistance, even in multiple layered graphene stacks- both of which are great properties for transparent electrode applications. There have been many cases of graphene derivatives being employed as both the anode and the cathode in heterojunction solar cells. Some of the common molecules used in these graphene derivatives including polyethylene naphthalate (PEN), PEDOT, PSS, MoO3 and ZnO, to name a few. PEDOT:PSS layers are the most common in graphene transparent electrdoes, with other materials being incorporated to improve and/or tune the properties. Using a graphene-based dual electrode system, flexible solar cells have been fabricated using different graphene derivations. PEN substrates containing various combinations of graphene, PEDOT:PSS, PTB and inorganic oxides generally show a PCE of 6.1-6.9% for the anode and 6.7- 7.1% for the cathode. These solar cells have also been found to exhibit a short-circuit photocurrent density up to 14.8 mAcm-2, an open circuit voltage up to 0.71 V, with the potential to obtain a form factor of up to 57.6% after 100 tensile flexing cycles (or 20 flexing cycles). Solar cells from these composite dual graphene electrodes have found to show no loss of activity under mechanical tension binding tests, a high efficiency and excellent mechanical strength. Another range of graphene bi-electrode solar cells incorporating PEDOT:PSS, copper and Buckminster fullerenes (C60) into the electrodes, where one electrode is doped with gold particles (in the form of gold (III) chloride). The doping of the graphene electrode changes the wetting in the PEDOT:PSS layer on the surface of the graphene sheet. The change in properties leads to an enhances PCE performance across the whole cell. Solar cells of this variety have been produced using 1-3 layers of graphene sheets. The solar cells electrodes can have a sheet resistance between 300 and 500 Ωm-2, with a transmittance ranging between 91.2-97.1%. The PCE of such solar cells are found to be around 1.63%. The PSS can be replaced by polyethylene glycol (PEG) to produce a solar cell which is less corrosive in nature (PSS is a strong acid). However, compared to other cells, the PCE is much lower so it’s not generally used. An alternative to using PEDOT:PSS is MoO3. This has been used by some researchers to produce a different kind of hole transport layer. In these cells, low pressure CVD-grown graphene is used as the graphene source. These cells consist of anode composed of graphene, MoO3, C60 and copper phthalocyanine (CuPc). This is a similar composition to many PEDOT:PSS electrodes and allows for a direct comparison in performance- one of the many reasons why the composition was chosen. Depending on the thickness of the hole transport layer, the PCE of these solar cells can range from 0.71-0.31%. While the PEDOT:PSS reference cell exhibited a PCE of 0.85%, this cell class exhibit a much higher PCE than transition metal electrodes, where Mg/Al electrodes exhibit the highest at 0.56%. Another area of graphene transparent electrodes research explores zinc-graphene anodes. Some researchers have developed a hybrid photoanode, based around a P3HT, ZnO and ZnS core-shell nanorod array, suspended on a reduced graphene oxide film modified with ITO. Each component has a specific function within the electrode, the P3HT acts the hole acceptor, the ZnS as the mediator and the ZnO is transporter and conductive collector. In these anodes, the PCE is enhanced by the presences of both a reduced graphene oxide film and ZnS/ZnO nanorods, showing a PCE greater than 1.01%. This is two and half times the PCE of the electrodes that don’t contain graphene, although still not as high as other solar cells. There have also been many other attempts to improve the photovoltaic performance of both the transparent electrodes and the solar cells as a whole. Various multilayer electrodes based around graphene, gold, P3HT, PCBM, PEDOT:PSS, copper and PMMA in various compositions have been employed with significantly different results. The transparency of these electrodes varies from 82.3% to 90% with sheet resistances varying massively between 92 Ωm-2 and 374 Ωm-2. The PCE of such electrodes can vary between 1.17% and 13.3%. ## Graphene Photoactive Layers Both graphene and graphene oxide can also be employed in heterojunction solar cells as photoactive layers in the form of an active interfacial layer, electron-hole separation layer, hole-transport layer or as an electron-transport layer. As a general class of materials, graphene photoactive layers can exhibit a PCE from anywhere between 0.4 and 10.3% depending on the graphene derivative and the type of photoactive layer being produced. There are currently hundreds of graphene photoactive layers being employed as heterojunction solar cells. Photoactive layers composed of a few layers of pure [graphene film](https://www.cheaptubes.com/product-category/cvd-graphene-films/)s whether produced by CVD, flame pyrolysis, or other exhibit a PCE range between 1.01-2.88%. They can be employed as n-type heterojunctions by utilizing n-type type silicon alongside the graphene layers. Doping with nitric acid increases the PCE of these pure graphene heterojunctions up to 4.35%, where up to 4.18% of the PCE can be retained after 10 days. Graphene can also be coated onto n-type silicon nanowire arrays, where the nanowires suppress and harvest light much better than their planar counterparts. However, they do show a lower PCE value than planar graphene-silicon heterojunctions, even after doping with thionyl chloride. Planar graphene-silicon solar cells can also be doped with thionyl chloride show a PCE lower than nitric acid doping, but greater than that of pure graphene-silicon heterojunctions with a PCE of 3.93%. The highly volatile nature of thionyl chloride is responsible for the lower doping effects compared to nitric acid. The interface of the heterojunctions is the most important part and a single layer of CVD-grown graphene (97% transparency, 350 Ωm-2) on silicon can exhibit a PCE of 5.38-7.85%- much greater than multilayer graphene heterojunctions. This value can be increased even further to 8.94% by the incorporation of an antireflection layer of silicon dioxide. Aside from pure graphene, many graphene hybrid materials exist as photoactive layers. One such example is that of lithium neutralized graphene oxide (GO-Li) as an interfacial layer between the photoactive layer and electron transport layer of solar cells. The incorporation of such layers can increase the PCE of a solar cell by up 6.29% compared to solar cells without the GO-Li layers. The thickness of these layers can tune the photovoltaic performance, with thicker layers producing a higher increase in the PCE. This layer also improves the stability of the solar cell under solar exposure, moisture and air. Graphene quantum dots and crystalline silicon can be used as electron blocking layers to prevent charge carrier recombination at solar cell anodes. In these cells, surface passivation can occur due to differing terminal groups, namely, oxide, hydrogen and methyl moieties. Cells containing the methyl terminal group show the best PCE of up to 6.63%, compared to 2.24 and 2.92 for hydrogen and oxide terminal groups. However, degradation can occur over time and the short circuit value can drop by more than 5 mAcm-2 and the PCE can drop by up 1.2%. Graphene oxide can be used with gold nanoparticles to produce anodic buffer layers. Capping agents are utilized in these hybrids, generally in the form of glycine or sodium citrate and can show a PCE ranging from 2.82-3.34%. However, the inclusion of P3HT and IBCA into the solar cell can increase the PCE up to 5.10%. Graphene oxide nanoribbons (GORs) can be used a hole extraction layers in many solar cells. These layers have been developed to replace existing ITO-based materials and have so far managed to increase the PCE of a solar device from 2.20% to 4.19%. Aside from the PCE, the incorporation of GORs produce a lower sheet resistance and a higher shunt resistance compared to their ITO counterparts. Electron extraction materials in solar cell devices can be fabricated using Cs-neutralized graphene oxide. Solar cells utilizing these materials have been found to exhibit PCEs up to 3.67%. However, more importantly, the photoactive layer has been found to operate independently to the electrode materials, in both normal and inverted devices. The charge neutralization ability of these materials can reverse the charge extraction properties in heterojunction solar cells. One of the most efficient graphene photoactive layers is produced from a hybrid material containing graphene oxide, PEDOT:PSS and n-type silicon nanowires. The wt% of graphene oxide has a profound effect on the PCE of the device with the optimum concentration being 30%, which produces a PCE of up to 9.57%. In comparison, the substitution of silicon nanowires for planar silicon produces a massive drop in the PCE to 4.30%. These layers not only show a high optical transparency compared to non-graphene photoactive layers of a similar composition, but also exhibit a reduction in the exciton decay. ## Graphene Schottky Junction GaAS Solar Cells GaAs solar cells have been one of the most widely studied type of heterojunction, namely Schottky junction, solar cells. Despite the large amount of research, only a few have reached PCE levels comparable to that of other heterojunctions and PSCs. However, the ones which have achieved high PCEs are some of the most efficient graphene-based solar cells. GaAs has a superior band-gap to silicon, with a charge carrier mobility that is six times higher. Theoretically, GaAs heterojunctions have the potential to produce efficient solar cells, but the devices currently being produced vary in quality. One of the cells that is less favorable than it's high-flying counterparts is based around CVD-grown single and multilayer graphene on n-type GaAs substrates, which only shows a PCE of 1.95% and an open circuit voltage of 0.65 V. Another such example is that of pillar-array-patterned silicon substrate with graphene, which only shows a PCE up to 1.96%. With nitric acid doping, the cell can achieve a PCE of up to 3.55%, but it's still lower than many other solar cells. By comparison, a Schottky junction solar cell made from CdS nanowires and graphene has only achieved a PCE of 1.65%, showing that there is a wide range in terms of quality, not only with GaAs solar cells, but with Schottky junction solar cells in general. Of the higher achievers, one example is that of a solar cell composed of an n-type silicon and TFSA- doped graphene Schottky junction. The synthesis approach is simple and a PCE of up to 8.6% can be achieved, which is 4.5 times higher than that of its un-doped counterpart and 6 times greater than other GaAs solar cells. The doping of TFSA on these devices not only increases their performance, but also enhances the stability of the device, compared to an un-doped version, to both oxygen and moisture. One of the better-quality GaAs solar cells is that of a cell which is composed of a GaAs substrate and graphene, with a silicon nitride (SiNx) insulating layer and silver ‘fingers’. These solar cells have achieved much better efficiencies than many other solar cells, with PCEs varying between 10.4% and 15.5%. By optimizing the open circuit voltage, junction ideality factor, graphene resistance and the internal interfacial contact, there is a theoretical possibility to achieve a PCE of up to 25.8% with these solar cells. Solar cells composed of graphene/semiconductor van der Waals Schottky diodes, with a tuneable gate and Fermi level, lead the way in terms of efficiency. The heterojunction utilizes a graphene- dielectric-graphene gate to achieve a PCE of up to 18.5%- much higher than other GaAs solar cells. The open circuit voltage, while not the best compared to other solar cell classes, is better than many other GaAs solar cells, with a value of 0.96 V. Aside from producing a highly efficient solar cell, there are theoretical predictions that the PCE of these cells could be increased to 23.8%. The last two GaAs solar cells, show values close to commercially ready solar cells, and until recently, silicon-based solar cells had only reached a PCE of up to 22.5%. So, with a bit of optimization, and despite the discrepancies in quality over the whole class of solar cells, some GaAs could reach efficiencies comparable to commercial solar cells. Recent developments in silicon-based solar cells has achieved a PCE of up to 26%, but this has only just been discovered and is currently confined to academic laboratories. ## Frequently Asked Questions: Graphene Solar Applications ### How does graphene improve solar cell efficiency? Graphene improves solar cell efficiency through several mechanisms: it reduces reflectance of incoming solar rays by up to 20%, provides an ultra-transparent conductive electrode (97.7% optical transmittance for a single layer), enables faster charge carrier mobility than conventional materials, and can be doped to tune its electronic properties. These combined effects can yield a potential efficiency increase of up to 20% compared to traditional indium tin oxide (ITO) electrodes. ### What types of solar cells benefit from graphene? Graphene has demonstrated benefits across nearly every major solar cell architecture: graphene-silicon heterojunction cells, polymer solar cells, dye-sensitized solar cells (DSSCs), quantum dot solar cells, tandem solar cells, perovskite solar cells (PSCs), and organic solar cells. In each case, graphene typically serves as a transparent electrode, hole/electron transport layer, or active light-absorbing material depending on the cell design. ### What is the advantage of graphene over indium tin oxide (ITO) in solar cells? Graphene offers several advantages over ITO: it is mechanically flexible (enabling roll-to-roll fabrication of bendable solar panels), earth-abundant and lower-cost than indium (a scarce element), chemically stable, and can be deposited over large areas via CVD. ITO is brittle, expensive, and becoming a supply-constrained material as demand for transparent electrodes grows in displays and photovoltaics. ### What is doped graphene and why is it used in solar cells? Doped graphene has foreign atoms or molecules introduced into its carbon lattice to alter its electrical properties. P-type doping (with trivalent atoms like boron) creates electron holes in the valence band, while n-type doping (with pentavalent atoms like phosphorus) adds free electrons. In solar cells, doping enables graphene to act as a selective charge transport layer — extracting either holes or electrons from the absorber and blocking the opposite carrier — which reduces recombination and improves open-circuit voltage. ### Are graphene solar cells commercially available? As of 2024, graphene solar cells remain primarily in the research and pilot-production stage. Graphene-perovskite and graphene-silicon cells have achieved laboratory efficiencies competitive with commercial silicon panels, but large-scale manufacturing challenges — including uniform CVD graphene deposition and long-term stability — are still being solved. Graphene materials (including graphene oxide and reduced graphene oxide) used in solar cell research are commercially available from suppliers like Cheap Tubes Inc. ## Graphene Solar Cells Design of Experiments ### Graphene Transparent Electrode To produce a graphene transparent electrode for heterojunction solar cells, first, produce or purchase CVD-grown graphene on copper foil. To prepare this electrode, a modified transfer method is needed. To transfer, deposit PMMA and cure, followed by etching of the copper foil with FeCl3 solution and rinse with deionized water three times. The next stage is to rinse the PMMA-graphene with deionized water and place on a glass substrate. Re-deposit one drop of PMMA onto the material, cure and remove the PMMA with acetone. Dope the transferred graphene film with HNO3 vapor (69% concentration, 10 seconds). To fabricate the device itself, the preparation of a silicon wafer with PEDOT:PSS is required. Clean a silicon wafer with acetone, ethanol and deionized water for half an hour and treat through chlorination and alkylation. Incorporate PEDOT:PSS with DMSO (5 %wt) and Triton (1 %wt) and stir to ensure through mixing. The fabricate the cell itself, use physical vapor deposition (PVD) and deposit LiF (0.6 nm) and Al (200 nm) electrodes onto the back of the silicon wafer. Spin-coat the PEDOT:PSS solution onto the silicon wafer and graphene-glass substrate (4000 rpm, 1 minute, 70-80 nm thickness). Anneal the organic films (125 °C, 30 minutes) in a glove box. Encapsulate the solar cell, using a clamp and AB glue to firmly stick the silicon wafer and the graphene-glass substrate together. ### Graphene Ga/As Solar Cell The promising Ga/As solar cell has the potential to be further optimized for commercial use. Firstly, purchase or grow CVD-graphene on copper foil. Next, remove the oxides on the Ga/As wafers by dipping them in HCl solution (10 %wt, 3 minutes) and attach gold contacts (60 nm thickness) onto the back surface of the wafer by thermal evaporation. Deposit a SiNx layer (80 nm) on top of the Ga/As surface by plasma enhanced CVD with a lithography-processed mask, to act as the insulating layer between Ga/As and graphene. Open a window (active area) on the Ga/AS by dipping in HCl solution (10 %wt, 5 minutes) and rinse with deionized water. Treat the active area using NH3 plasma treatment (5 min with a 120 W 27.5 MHz RF generator). Transfer the graphene sheet onto the substrate using PMMA as a support. Remove the PMMA with acetone and paste silver onto the graphene, above the SiNx area, followed by annealing (120 °C, 5 minutes). Spin coat TFSA (bis(trifluoromethanesulfonyl)amide) to dope the graphene. Add an antireflection layer- an electron beam evaporated Al2O3 film (68 nm thickness). To prepare the gate, transfer an extra layer of graphene onto the active area that is coated with Al2O3 by the same method as before. Remove the PMMA and paste the silver gate electrode onto the graphene gate, followed by annealing (120 °C, 5 minutes). ### Graphene Solar Cells Future Advancements Solar cells are a topic of intense research in academia and industry alike with new advancements being realized all the time. Most solar cells being produced utilize silicon and inorganic-based materials, which are at some point going to reach their limitation. The incorporation of organic molecules of graphene derivatives, low band-gap polymers, or both, are set to revolutionize the industry and lead to many commercially viable solar cell device architectures. There has been tremendous progress so far into graphene-based solar cells and this is going to continue well into the future. The ability to optimize various parameters makes graphene-based solar cells highly tuneable and adaptable to future challenges in solar research. Whether through improving existing solar cells, improving the properties of current non-graphene-based solar cells, or by creating a new range of graphene photovoltaics it is evident that graphene has a role in this exciting and rapidly advancing field. **References:** Huang X., Xiaoying Q., Boey F. and Zhang H., Graphene based composites, Chem Soc. Rev., 2012, **41**, 666-686 Singh E., Nalwa H., Graphene-based bulk-heterojunction solar cells: A Review, Journal of Nanoscience and Nanotechnology, 2015, **15**, 6237-6278 Li P., Chen C., Zhang J., Li S., Sun B., Bao Q., Graphene-based transparent electrodes for hybrid solar cells, Frontiers in Materials, 2014, **1**, 26 Guo X., Lu G., Chen J., Graphene-based materials for photoanodes in dye-Sensitized solar cells, Frontiers in Energy Research, 2015, **3**, 50 Ye Y., Dai L., Graphene-based schottky junction solar cells, J. Mater. Chem., 2012, **22**, 24224 Feng T., Xie D., Lin Y., Zang Y., Ren T., Graphene based Schottky junction solar cells on patterned silicon-pillar-array substrate, App. Phys. Lett., 2011, **99**, 233505 Jie W., Zheng F., Hao J., Graphene/gallium arsenide-based Schottky junction solar cells, App. Phys. Lett., 2013, **103**, 233111 Miao X., Tongay S., Petterson M., Berke K., Rinzler A., Appleton B., Hebard A., High Efficiency Graphene Solar Cells by Chemical Doping, Nano Lett., 2012, **12(6)**, 2745-2750 Li X., Zhang S., Wang P., Zhong H., Wu Z., Chen H., Liu C., Lin S., High performance solar cells based on graphene-GaAs heterostructures, Nano Energy, 2015, **16**, 310 Li X., Chen W., Zhang S., Wu Z., Wang P., Xu Z., Chen H., Yin W., Zhong H., Lin S., 18.5% efficient graphene/GaAs van der Waals heterostructure solar cell, Nano Energy, 2015, **16**, 310-319 Yoshikawa K., Kawasaki H., Yoshida W., Irie T., Konishi K., Nakano K., Uto T., Adachi D., Kanematsu M., Uzu H., Yamamoto K., Silicon heterojunction solar cell with interdigitated back contacts for a photoconversion efficiency over 26%, 2017, Nature Energy, **2**, 17032 ## Related Reading Go deeper on related topics: - Most Sensitive Carbon Nanotube Photodetector — CNT photodetector breakthrough — complementary to graphene photoactive-layer research. - Functionalization of Graphene Nanoplatelets — graphene surface chemistry research — directly applicable to charge-transfer interface engineering in graphene solar cells. - Graphene Sensors — graphene transduction physics outside photovoltaics — useful context for light-harvesting device designers. --- ## Graphene Biosensors Source URL: https://www.cheaptubes.com/graphene-biosensors/ Last updated: 2026-04-23 --- **At a glance:** Graphene-based biosensors leverage graphene's high electrical conductivity, large surface-to-volume ratio, and biocompatible surface chemistry to detect biological analytes — glucose, proteins, DNA, pathogens — at very low concentrations. Common architectures include field-effect transistors (GFETs), electrochemical electrodes, and surface-plasmon-resonance devices. Performance depends on graphene purity, oxygen functional groups, and immobilization chemistry. Cheap Tubes supplies research-grade graphene, graphene oxide, and CVD graphene films suitable for biosensor prototyping. ## Properties and Principles of Graphene Biosensors Graphene’s mechanical, electrical and optical properties are the most useful for biosensing applications. It’s high mechanical strength, Young’s modulus, flexibility, and tensile strength are key properties during the fabrication process, as the surface is strong enough to be easily modified/be used to modify other surfaces. Efficient biosensors work by providing a high electron transfer rate between the electrode and the biomolecule. Graphene’s high charge mobility and electron transfer properties help to facilitate the electron movement between the target biomolecule and the sensor, making it a useful material in biosensing applications. The doping ability and electrical conductivity of graphene makes it an ideal choice for mobilizing charge carriers in a sensor. When biomolecules are adsorbed onto a sheet of graphene, a change in the charge carrier density changes the electrical conductivity. The change in conductivity causes an electrical response that is measurable, which can be used to identify whether a molecule has been sensed or not. Graphene is also transparent to visible-light wavelengths, making it useful in optical-based biosensors where the higher density of states of a biomolecule improves the surface electromagnetic wave propagation. Optical properties can be utilized in such situations where DNA bases wish to be identified, but not double stranded DNA. There are also four principles that are utilized when graphene used to sense biomolecules. These are: using graphene as electron transfer materials, electrochemical impedance materials, as field effect transistors (FETs) and as photon/phonon transfer materials. Electron Transfer Materials Graphene is exploited as an electron transfer material because its high surface area can expose all of the carbon atoms to the target biomolecules, increasing the sensitivity (or it gives the potential for an increased sensitivity). The low noise also gives a higher sensitivity. Graphene can also be used as an electric transfer medium in sensors, where its high mobility and electrical conductivity help to facilitate the movement of charge and electron through the sensor. Graphene is also able to act as an electron transport material by physically binding to the biomolecule and shifting electrons through bonding interactions. Impedance Materials To be used as an impedance material, graphene can be used to functionalise the electrode surface within a biosensor. Graphene’s delocalised π-network forms π-π stacking interactions which can anchor other π-conjugated molecules onto the electrode. This method provides a method to modify the surface of graphene in biosensors without disturbing its desirable electrical conductivity properties. The high surface area of graphene provides many anchoring/binding sites for both target molecules and fabricated metal nanoparticles (which are sometimes used to improve the sensing efficiencies of biosensors). The aromatic domains on the graphene sheet (and ionic regions if metal nanoparticles are present) allow the graphene sensor to interact in various ways, which can increase the sensitivity against non-graphene biosensors. FETs Using graphene as a suspended FET in FET-biosensors produces an enhancement in the sensitivity, owing to the interfacial charge traps which act as external scattering centres and degrade transport properties. Graphene is incorporated into two types of FET-based biosensors- back gate and liquid gate. In back gate FETs, the change in a threshold/source-drain voltage causes the conductivity of graphene to change, allowing for a higher sensitivity to be recorded. In liquid gates FETs, graphene is very susceptible to a change in the surrounding liquid environment, whether it be by ion density or a surface charge, which produces a higher detection sensitivity compared to other non-graphene liquid gate FET biosensors. The surface of the graphene sheet can also be functionalised to be selective to a single biomolecule. The graphene sheet can detect electronic changes in the surrounding liquid medium by two different mechanisms- electrostatic gating mechanisms and surface transfer doping. Electrostatic gating mechanisms exploit the hole density, which leads to a change in the overall conductivity of graphene causing a sensing response. Surface transfer doping is when a dopant/biomolecule induces a shift in the gate voltage of the graphene gate and causes a left shift of the Dirac point by a charge transfer mechanism, which represents a transfer of electrons from the biomolecule to the graphene gate. Such mechanisms invoke a response which can be detected and measured i.e. the electron transfer causes the molecule to be sensed. Direct binding of biomolecules can also invoke a similar response, as the number of electron scattering centres becomes increased, resulting in a decrease in the mobility of graphene’s charge carriers. Photon/Phonon Transfer There are two main mechanisms that determine photon and phonon transfer through graphene. These are electrochemiluminescence (ECL) and fluorescence. ECL (without graphene) has two mechanisms; annihilation and co-reactant. Both mechanisms involve intermediate complexes undergoing an electron transfer reaction on the surface of the electrode. Such mechanisms promote electrons into higher orbital states, where upon light is released when they return to their ground state. Graphene, however, produces two opposing mechanisms; ECL enhancement and ECL quenching. Graphene’s intrinsic electrical conductivity and mobility promote the quantum yield of the luminophore, which is normally limited by the electron transfer of a number of linked luminophores. Graphene’s efficient electrical properties promotes efficient electron transfer which induces a greater concentration of intermediate species to higher electronic states, per unit time. This, coupled with graphene’s high surface area provides a high concentration of sites for both luminophores and target biomolecules, all of which increases the sensitivity of the sensor. Graphene (particularly GO) can also quench the ECL mechanism due to resonance energy transfer. There is a critical point for ECL intensity. Below this, the incorporation of graphene into the sensor increases the ECL intensity. Above this, the ECL intensity will decrease, even if graphene is continued to be added into the matrix. This mechanism is not fully understood to date, but it is believed to be a product of the blackbody effect. Graphene also has the ability to fluoresce and quench fluorescence. Graphene can be used in sensors to detect the fluorescence imposed onto the graphene (or GO) sheet by photo-induced charge transfer and fluorescence resonance energy transfer mechanisms. Graphene (and GO) can also be used as an energy quencher for organic fluorophores and nanomaterials. The quenching mechanism for these types undergoes also undergoes a fluorescence resonance energy transfer mechanism. ## Glucose Biosensors With more than 30 different derivatives documented, graphene sensors that can detect glucose are a widely-established area. Depending on the type of sensor, sensitivities can range from 0.64-1100 µA mM-1 cm -2 and the linear range can vary between 0.05 µm and 32 mm. Many types of graphene electrode can be implemented into glucose sensors. Glucose sensors today contain many graphene derivatives that are composited with both biological and non-biological materials. The two main types of graphene electrodes employed in glucose sensors are enzymatic and non-enzymatic electrodes. The most common glucose sensors are developed using enzymatic components and the sensing range for a glucose sensor generally lies between 1-60 mM. This is also the range for both diabetic and non-diabetic blood glucose levels. Whilst many variations of graphene can be utilised (including graphene nanosheets, nanoflowers, nanocubes, graphene ionic liquids, poly-functionalised graphene and graphene paper), pure graphene and reduced graphene oxide (rGO) are the most common graphene derivatives used in glucose sensing. They form a wide range of composites with metal nanoparticles, polymers and conducting polymers, which are used to modify electrode surfaces. The sensing of glucose relies on two main factors- the efficient transfer of electrons between the glucose and the graphene and the presence of a catalytic material. The interaction of glucose and graphene produces well-defined redox peaks, which provides and efficient electron transfer system. The redox potential between glucose and graphene is reversible, with a rate constant is 2.83 s-1, which is a much higher rate when compared to other carbon allotrope sensors, e.g. CNTs. Graphene also exhibits a high loading capacity of glucose onto its surface, due to its high surface area. Graphene glucose sensors almost always utilise metal nanoparticles on their surface due to their ability to enhance the sensitivity, electron transfer and response times. An inexpensive, non-enzymatic, disposable sensor strip has been developed on the small scale, using a copper-graphene nanocomposite, to measure the glucose concentration in human tear fluids. The electrodes in these sensors contain surface modifications of copper nanoparticles, as the size and distribution of such nanoparticles play a big role in the optimization of the sensor. A larger copper concentration increase the output of the signal, due to an increased number of reactions between the copper ions and the glucose molecules. The incorporation of graphene in the matrix creates a uniform distribution of copper NPs by controlling the electrodeposition under an applied voltage. By using oxygenated graphene (GO, rGO etc), the surface functional groups help to bind the copper nanoparticles in place, which helps to facilitate the exhibited uniform distribution. These glucose strips show a linear relationship between the current applied and the amount of glucose sensed, with an optimal working potential of 0.5 V. These sensors have a sensitivity of 1101 µA mM-1 cm-2 with detection limits between 0.025 and 0.9 mM. These glucose strip sensors are also consistent, with a reproducibility of 91%. They also show a high stability. After 10 sensing cycles (with an applied current), over a 30-day period, the sensors have shown to exhibit a maximum loss of 17.2%. Enzyme-modified graphene solution-gated transistors can be used as high performance glucose sensors. These glucose sensors are a type of solution-gated graphene transistors (SGGTs). SGGT’s have been found across various applications to provide, real-time, sensitive sensing with a high throughput. They can also operate in low voltages and aqueous environments, both of which are valuable properties for sensing biomolecules. The sensing mechanism of these sensors revolves around interactions between the biomolecules and the sensors channels/gates. The channels and gates in these glucose sensors are made of CVD graphene and the gate electrodes are modified with glucose oxidase (GOx) enzymes, biocompatible polymers and platinum nanoparticles. The sensors work by oxidizing the glucose (GOx catalysed reaction) which generates hydrogen peroxide at the gates. The hydrogen peroxide is then oxidized, which regulates the effective gate voltage applied on the transistor. The sensors are sensitive to the voltage changes, which allows for a detection signal to be recorded. These sensors can show detection limits for glucose and hydrogen peroxide at 0.5 µM and 30 nM, respectively. The high sensitivity of these sensors make them a great candidate for non-invasive glucose sensors, which detect glucose in human bodily fluids such as saliva. Other SGGTs which have been modified with glucose oxidase have also been recorded, with detection limits of 0.1-10.9 mM. Other notable glucose sensors are those containing Nafion/GOx/multilayer film of ionic liquid–sulfonic acid-functionalized graphene, GOx/TiO2 NP-graphene/GCE and Pt nanoflowers/GO/GCE, which show sensitivities of 0.0718 nA µM-1, 6.2 µA mM-1 cm-2 and 0.64-1.26 µA mM-1 cm-2, respectively. 3-D graphene foam modified with cobalt oxide nanowires also show a very low detection limit of 25 nM. **DNA** Graphene can be used to distinguish individual nucleotide bases, single strand DNA and double strand DNA. One of the simplest single strand DNA detection mechanisms is via immobilization of the DNA strand onto a functionalized graphene sheet (GO, rGO etc). Single strand DNA exhibits an orientation where all the nucleobases lie flat, which is favourable due to graphene’s planar/flat nature and high surface area. The bonding and hybridization between the amino-terminated groups of the DNA and the oxygen-based functional groups on the graphene sheet form amide bonds. Using a graphene sheet with a higher concentration of carboxylic acid groups (i.e. rGO), improves the surface interaction between graphene and the DNA strand, due to the increased number of potential binding sites. Functionalized graphene can also bioconjugate with terminal sulphur groups on single strand DNA, although this is less common. The absorption of single strand DNA is very efficient, to the point where most of the bases become absorbed on to the graphene sheet and the helical structure can be destroyed. Sensors based around various principles including fluorescence, electrochemical, electrical and SERS assays can be used for sensitive and selective double strand DNA recognition. Double strand DNA does not bind as strongly to graphene as single strand DNA does, due to a lower number of intermolecular interactions at the reactive interface. Single and double strand DNA can be differentiated by sensors using other non-conventional various methods with graphene as the binding material, including colorimetry, chemiluminescence and mass spectrometry. Many sensing methods for the detection (and differentiation) of DNA using graphene revolve around π-π stacking interactions and other intermolecular forces. Graphene utilizes its exposed edge planes to catalyse and oxidise DNA bases better than any other electrode material. A sensor modified with graphene can exhibit up to a 4-fold greater sensitivity to DNA bases than other materials (including other carbon allotropes such as CNTs). Some reduced graphene oxide, dependent upon their functionalization, can detect and distinguish all four nucleotide bases and polymorphism in short oligonucleotides. All the four bases exhibit different local density of states (LDOS) and interaction energies. The LDOS leave fingerprints specific to each base, which can be detected by local electron tunnelling conductance. The high conductivity of graphene allows for a higher detection sensitivity of these fingerprints. There are many different types of DNA sensor currently being researched, which incorporate the various mechanisms and principles discussed. One example is the utilization of graphene oxide and NaYF4:Yb,Er@SiO2 nanoparticles. Like many DNA sensors, the driving mechanism is based around the π-π interactions between the carbon atoms (of the graphene) and the nucleobases (of the DNA). The interaction produces a fluorescence resonance energy transfer (FRET) quenching mechanism due to the overlap of the emission and absorption spectrums. These sensors have shown detection limits as low as 5 pM, with a selectivity for single stranded DNA. A graphene-FET based sensor has also been developed to detect mismatched DNA and polymorphisms. These graphene sensors have a much simpler and cheaper fabrication compared to other polymorphism sensors. They also have a high specificity and the ability to detect a single nucleotide mismatch. The sensors measure a resistance induced by a displaced nucleotide strand, which induces a current change (of which graphene is highly sensitive to) and a shift in the Dirac point. The main advantage of these sensors is the ability to detect a single mismatch which is label-free and with high resolution. These sensors are a very recent discovery which have the potential to form the basis for a commercial diagnostic point of care tool for early treatment of life-threatening diseases. Graphene quantum dots (GQDs) have also started to gain attention as DNA sensors. Double strand has a poor affinity to large sheet graphene, hence the preference to single strand selectivity. GQDs show a higher intercalation with DNA due to their smaller size. The higher intercalation can promote DNA cleavage, so there is a future potential for GQDs to be a selective sensor for double strand DNA, once optimized. There are many different types of sensor for detecting various DNA forms. Other notable sensors include a ssDNA/azophloxine/graphene nanosheets sensor with a detection limit of 0.4 fM, a ssDNA/Au nanorods/GO/GCE sensor with a detection range of 0.035-3.5 fM and a ssDNA/GO–chitosan/ITO sensor with a detection limit of 10 fM. ## Protein Biosensors Another growing area with graphene based sensors is in the detection of proteins. Protein sensors are used to detect complex proteins such antibodies and biomarkers for use as diagnostic testing tools. Many protein sensors without graphene suffer from a lack of flexibility, making graphene a great material for composite protein sensors. A graphene nanoFET protein biosensor has been developed using CVD-grown graphene to detect thrombin biomarkers. Unlike other graphene-based FETs for protein sensing (which generally use exfoliated graphene), the use of CVD-grown graphene allows for an easier scalability, easier fabrication procedure, larger sensing area and are reusable. They also provide similar advantages to other similar sensors such as low noise and high transconductance. The sensor is used to detect real-time binding (and unbinding) of thrombin protein biomarkers using the change in electrical current produced by the binding-unbinding mechanisms. These sensors are also able to measure the binding kinetics during the binding-unbinding processes. These sensors have an effective gate voltage of 0.21 mV min-1, with a dissociation constant of 170 nM. The sensor can be regenerated with a simple rinse of buffer solution, which removes any bound protein on the surface. The surface of the sensor also contains a DNA aptamer which is specific for binding to thrombin. These DNA aptamers have a half-life of 10 hours i.e. 50% of the aptamer will have removed itself after 10 hours, but the device themselves have a shelf-life of over a week. A protein sensor using thermally reduced graphene oxide (TRGO) and gold nanoparticles conjugated with antibodies. The sensor response, like many biosensors, occurs when a protein binds to the nanoparticle/antibody conjugates which induces a change in conductivity in the TRGO sheet. The signal is recorded by FET and direct current measurements. They are fabricated via many techniques including e-beam lithography, dispersion and suspension methods and multiple annealing steps. The AuNPs tested so far have been 10 and 20 nm in diameter, with 12 and 48 antibodies per each NP, respectively. These sensors have a much higher sensitivity than many other carbon-based protein sensors, with a detection limit of 0.2 ng ml-1. This sensor has been developed off an unoptimized predecessor with an order of magnitude improved sensitivity, so the potential for these sensors may not have yet been reached, and the sensitivity could be further increased (although this has been stated by the researchers themselves that it would be a hard task). A primitive bioelectronic sensor to detect proteins that fluoresce using a graphene FET with biological and inorganic functional groups has also been developed. The sensor works by detecting tagged proteins (e.g polyhistidine) which bind via the tag itself. The device provides an electric readout for each given protein by measuring the proteins optimal excitation wavelength. By knowing the excitation wavelength and making the surface multi-functional, they have the potential to be used as diagnostic tools in the future for the detection of various protein species. The single protein detection devices to date adopt a p-type structure with a hole mobility’s between 300-2000 cm2 V s-1. ## Other Small Biomolecule Biosensors Aside from the main three biosensors described, other small biomolecules such as cells, electroactive analytes, dopamine and uric acid (to name a few) can now be detected by various graphene-based sensors. Graphene can be used as a biocompatible substrate to enhance the adhesion and growth of cells to detect cell populations. Graphene oxide with a negatively charged surface can be used to interact with positively charged poly-L-lysine, which results in a biocompatible interface that promotes cell adhesion for the detection of 30 cell mL-1. A composite film of chemically rGO and carboxymethyl chitosan with folic acid molecules anchored to the surface can be used for the detection of tumour cells which have a folate receptor, at a rate of 500 cells mL-1. Another nanocomposite consisting of chemically rGO and 3,4,9,10-perylenetetracarboxylic acid can be used to detect breast and cervical carcinoma cells at a rate of 1000 cell mL-1. These nanocomposites are deposited onto an electrode where the carboxylic acid groups are linked to a specific aptamer that binds to nucelolin (and overexpressed protein in the carcinoma cells). A common component of many small molecule sensors is either GCE or a graphite/GCE composite. However, many of these are being phased out and chemically reduced graphene oxide is being used to replace the graphite component, mainly due to its higher electron transfer rate. The oxidation/reduction potentials to detect H2O2 (a common enzymatic byproduct) for GCE/Chemically rGO are 0.2/0.1 V compared to 0.8/-0.35 V and 0.7/-0.25 V for graphite/GCE and GCE, respectively. Chemically rGO also exhibits a wide linear range with values between 0.05-1500 µM than other sensors due to a higher concentration of edge plane defect. Chemically rGO electrodes also show great electron transfer rates for NADH at 0.4 V, which is 0.3 V lower than GCE/graphite sensor electrodes. Chemically rGO electrodes show a great deal of promise in terms of linearity and limits of detection (LOD). For ascorbic acid, they show an LOD of 0.07 µM with a linearity of 0.1-106 µM. The electrodes can be heavily modified by a series of moieties, nanoparticles and inks to produce LOD’s that are wider ranging from 5 nM to 1.2 µM with linearity’s between 0.15-4500 µM. Chemically rGO/GCE electrodes shows a LOD of 0.12 µM and a linearity 0f 0.5-2000 µM for dopamine. Functionalized chemically rGO/GCE electrodes show LOD’s as low as 22 nM with linearity’s ranging from 0.2-4000 µM. For uric acid, chemically rGO/GCE has a LOD of 0.2 µM with a linearity of 0.8-2500 µM. Modified electrodes can show an LOD of 0.088 µM with linearity’s of 0.1-1000 µM. In previous non-graphene sensors, the selectivity between dopamine, uric acid and ascorbic acid has always been poor as the sensors could not distinguish between these three molecules. These are also three of the most studied small biomolecules. The sp2 planes and edge defects exhibited by graphene produces a greater number of π-π interactions that can be used to distinguish dopamine from other small biomolecules. There is still further work required to distinguish between other biomolecules, but using graphene instead of other carbon allotropes shows a step in the right direction for producing selective and sensitive small molecule biosensors. ## Design of Experiments Glucose Sensor There are many glucose sensors that can be fabricated, but here we focus on the SGGT sensor described above, as there is a great potential for this sensor to become more commercially available than other glucose sensors. To start, a series of solutions need to be prepared before fabrication. A CHIT polymer solution needs to made up (the rest can be used as purchased). To make the solution, dissolve CHIT (0.5g) in an acetic solution (100 mL, 50 mM, pH 5-6) and electromagnetically stir overnight store in a refrigerator (4 °C). Prepare a GOx stock solution by dissolving in PBS and storing in a refrigerator (4 °C). Dilute a 5 %wt Nafion solution 10 times with isopropanol before use. To fabricate the device, deposit Au/Cr source and drain electrodes onto glass substrates by magneton sputtering, using a shadow mask. The Cr is used as an adhesion layer for the Au. Grow single layer graphene by CVD on Cu foil (alternatively, this can be purchased) and transfer to the glass substrate with the Au electrodes. Pattern the graphene films by standard lithography to produce the graphene channel and gate. [In this case, the gate electrode was defined as 3 x 3 mm and the channel width and lengths were 0.2 and 3 mm, respectively]. Attach a PDMS wall to the substrate to enable the testing of the device in PBS solution. Modify the graphene gate electrodes with Pt NPs by electrochemical deposition (5 mM H2PtCl6/0.1 M HCl aqueous solution). Apply a constant voltage (+0.2V, 120 s) to optimize the deposition. Rinse the graphene/Pt NPs with de-ionized water and use as the gate electrode. To prepare the GOx-CHIT/Nafion/PtNPs/graphene electrode, mix the GOx stock solution (50 µL) with the CHIT solution (0.5 %wt) and sonicate for 15 minutes. Take the graphene gate electrode and drop Nafion (10 µL, 0.5 %wt) onto the surface of the gate and dry at room temperature. After that, drop coat the GOx-CHIT mixture (10 µL) onto the gate electrode and refrigerate overnight (4 °C) to dry the GOx-CHIT film. Wash the device with de-ionized water to remove unwanted residues and store in the refrigerator for future use. DNA Sensor Here we look at the novel sensor that has the potential for commercial use. As described above, it is a sensor that can detect mismatching of DNA to a single nucleobase mismatch, so it could have great importance once optimized. To fabricate the sensor, place the graphene onto copper foil and spin coat PMMA onto the topside of the graphene sheet. Etch away the bottom of the graphene. PMMA acts as the supporting layer for the graphene sheet after etching the copper. Remove the back-side of the graphene by oxygen plasma etching and cut into pieces with scissors (tests done to date use 4 x 6 mm pieces). Etch the copper by floatation with ammonium persulfate (0.1 M, 5 hours) and rinse with deionized water overnight. Transfer the PMMA supported graphene sheet onto a SiO2-coated silicon wafer, then remove the PMMA layer with acetone (60 °C, 1 hour). Anneal the sample under a hydrogen/argon atmosphere (300 °C, 2 hours). To fabricate the transistor, use silver paste as the conducting and drain electrodes at two ends of the graphene sheet. Use silicone rubber as the insulate for the source and drain electrodes. Protein Sensor Here is the detailed production step of a the nanoFET protein sensor, as described above. The sensor shows a great promise for scalability and larger scale production, so it is a great example of a sensor that should be reproduced and optimized. To make the sensor, first, either grow or purchase CVD-grown grapehene (on Cu foil) and spin coat PMMA (2% solution of 495 Mw PMMA in anisole) onto a square piece of graphene (1.5 x 1.5 cm). Place the coated graphene square into a copper etchant (4 hours) and then clean the device by soaking it in deionized water baths for at least 12 hours and transfer onto the device substrate (Si/SiO2 with 500 nm oxide and pre-defined alignment marks). Dry the device (30 °C, 4 hours) and remove the excess PMMA by open-air heating (350°C, 4 hours). Pattern graphene ribbons (3 µm x 10 µm) using photolithography and an O2 plasma etcher. After patterning, fabricate metal electrodes (1.5 nm Cr/30 nm Au) using standard lithography, metallization and lift-off methods. This leaves an exposed graphene area of 3 x 3 µm and is the active sensing area (24 in total over the device). Remove the residues by annealing the device (400 °C, Ar/H2 atmosphere). To make the surface preferential for protein binding, treat the device with pyrenebutanoic acid succinimidyl ester (PBASE) and a thrombin-specific DNA-based aptamer. ## Future Advancements Many graphene-based biosensors have only been tested on the small/laboratory scale. The next big step, like many graphene composite materials, is to optimize their sensitivity and selectivity to push production to commercial levels. For sensors that are looking to analyse *in-vivo, *discovering the* *toxicological and biocompatibility effects of graphene will* *decide if the sensors are to be used in this capacity. Many graphene biosensors exhibit similar sensitivities to other non-graphene biosensors, but can exhibit beneficial properties such as enhanced flexibility, conductivity and selectivity to certain molecules. To take these sensors to the next level in terms of production, an increase in the sensitivity to greater levels (to confidently surpass existing sensors) is needed, as is the ability to be able to select and distinguish between various biomolecules. The ability to do the latter will push graphene-based biosensors to significant heights above their non-graphene counterparts. This should be the focus and it is the property that will offer the most benefit for commercial applications e.g. as multi-functional diagnostic tools. ## References Kumar S., Luong J.H.T., Recent advances in electrochemical biosensing schemes using graphene and graphene-based nanocomposites, Carbon, 2014, **84(1)**, 519-550 Tehrani F., Reiner L., Bavarian B., Rapid prototyping of a high sensitivity graphene based glucose sensor strip, PLoS ONE, 2015, **10(12)**, 1-11 Wang F., Liu L., Li W., Graphene-based glucose sensors: A brief review, IEEE Transactions on Nanobioscience, 2015, **14(8)**, 818-834 Zhang M., Liao C., Mak C.H., You P., Mak C.L., Yan F., Highly sensitive glucose sensors based on enzyme-modified whole-graphene solution-gated transistors, Scientific Reports, 2015, **5:8311**, 1-6 Hu Y., Li F., Han D., Niu L., Biocompatible graphene for bioanalytical applications, Springer, 2015, **VIII**, Chapter 2, pages 11-33. Alonso-Cristobal P., Vilela P., El-Sagheer A., Lopez-Cabarcos E., Brown T., Muskens O. L., Rubio-Retama J., Kanaras A. G., Highly sensitive DNA sensor based on upconversion nanoparticles and graphene oxide, ACS Appl. Mater. Interfaces, 2015, **7**, 12422−12429 Hwang M. T., Landon B. P., Lee J., Choi D., Mo A. H., Glinsky G., Lal R., Highly specific SNP detection using 2D graphene electronics and DNA strand displacement, PNAS, 2016, **113(26)**, 7088-7093 Saltzgaber G., Wojcik P., Sharf T., Leyden M. R., Wardini J. L., Heist C. A., Adenuga A. A., Remcho V. T., Minot E. D., Scalable graphene field-effect sensors for specific protein detection, Nanotechnology, 2013, **24**, 355502 Mao S., Yu K., Lu G., Chen J., Highly sensitive protein sensor based on thermally-reduced graphene oxide field-effect transistor, Nano Res., 2011, **4(10)**, 921-930 Lu Y., Lerner M. B., Qi Z. J., Mitala Jr. J. J., Lim J. H., Discher B. M., Johnson A. T. C., Graphene-protein bioelectronic devices with wavelength-dependent photoresponse, Applied Physics Letters, 2012, **100**, 033110 ### Graphene Materials for Biosensor Research We supply graphene oxide, reduced graphene oxide, and graphene nanoplatelets optimized for biosensor electrode fabrication — including CVD graphene films for FET-based detection. Technical specs, SDS, and bulk pricing on request. [Shop Graphene Oxide →](https://www.cheaptubes.com/product-category/graphene-oxide/)[Shop Graphene Nanoplatelets →](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ## Graphene Sensors: Properties, Fabrication, and Applications Source URL: https://www.cheaptubes.com/graphene-sensors/ Last updated: 2026-04-17 --- # Graphene Sensors [image: graphene-sensor-electrode] A Graphene Electrode Suitable For Sensing As with other applications, graphene can be used to enhance existing properties and overcome limitations in various materials by transferring its unique properties into a hybrid/composite material. There are many ways in which graphene can detect molecules, making it an ideal choice as a material for use in sensors. Graphene’s intrinsic properties also makes it a good choice as a single-material sensor in many applications. ## How Graphene Sensors Detect Molecules Sensors work by detecting a voltage change in the presence of an analyte. Because graphene has excellent conductive, thermal and adsorption properties as well as a large specific surface area. It provides many avenues for a molecule to be sensed. Graphene is very sensitive to a change in its surroundings, which is one of the key properties that all good sensors possess. For sensor applications, the structure of graphene provides a unique surface for the adsorption of molecules. The defects present in a graphene sheet provide cavities that can improve the absorption efficiency of molecules to the surface, allowing them to be detected. Graphene can also act as a p-type semiconductor where they have hole-like charge carriers. For some applications, the depletion of holes from the valence band can lead to an increase in the resistance and therefore enhance sensitivity and response. The adsorption of molecules onto the surface can also trigger a change in the electrical conductivity of graphene. The surface adsorbates can either act as a donor or acceptor molecule, donating or removing electrons respectively. The voltage change with graphene, provides a measurable response which indicates that a molecule has been detected. ## Graphene Composite and Hybrid Sensing Materials In hybrid materials, graphene tends to form π-π stacking interactions with the other components. These interactions can induce a charge-transfer mechanism across the de-localized electrons, resulting in enhanced sensitivity. In addition to adsorbing into the cavities on the graphene surface, molecules can also interact with the π-bonds. This can lead to a greater number of potential adsorption sites which increases the sensitivity of the material. A higher incorporation of graphene into a composite material has been found to produce a larger π-network. Sensing is a large industry and has had a huge impact in across many industries. The ability to detect and distinguish at the molecular level has become increasingly important for the detection of contaminants in environmental processes; for a better understanding of how various electronics work; as well as how biomolecules interact. As advancements are made, the need to understand the underlying mechanisms becomes paramount to the development of sensing materials. Advanced sensors can answers these questions. ## Types of Graphene Sensor Applications Graphene (as a single molecule or a composite) is currently used in various sensing environments nowadays as biosensors, optical sensors, temperature and humidity sensors, piezoelectric and piezoresistive sensors, capacitance sensors and gas sensors. This series of graphene sensor guides details many examples of how graphene films and composites are utilized in sensor applications. ### Graphene Materials for Sensor Development We supply graphene oxide, reduced graphene oxide (rGO), and graphene nanoplatelets for gas, biosensor, and strain sensor research. CVD graphene films available for FET and GFET sensor platforms. [Shop Graphene Oxide →](https://www.cheaptubes.com/product-category/graphene-oxide/)[Shop Graphene Nanoplatelets →](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ## Fullerenes: Structure, Properties & Applications Source URL: https://www.cheaptubes.com/resources/fullerenes-properties-and-applications/ Last updated: 2026-04-23 --- **TL;DR:** Fullerenes are hollow-cage carbon allotropes — C60 (the soccer-ball Buckminsterfullerene, MW 720.64 g/mol, icosahedral symmetry) and C70 (ellipsoidal, MW 840.74 g/mol) are the most widely used. They're synthesized by arc-evaporating graphite rods in helium (the Kratschmer-Huffman method), then extracted with aromatic solvents and purified by HPLC. Fullerenes and their derivatives (PCBM, PC71BM, fullerenols, endohedral metallofullerenes) are benchmark electron acceptors in organic photovoltaics, n-type semiconductors in OFETs, molecular-scale lubricants, potent radical scavengers, and platforms for biomedical and energy-storage research. *By [Mike Foley](/about-cheap-tubes-inc/), Founder, Cheap Tubes Inc. — published April 2026* [image: ] ## 1. What Are Fullerenes? In 1985, Harold Kroto, Robert Curl, and Richard Smalley published a short paper in Nature* describing a new carbon allotrope: 60 carbon atoms arranged in a hollow, soccer-ball-shaped cage. The molecule was named **Buckminsterfullerene**, after Buckminster Fuller, whose geodesic domes it resembles at the molecular scale. Kroto, Curl, and Smalley shared the 1996 Nobel Prize in Chemistry for the discovery. What makes fullerenes distinctive is **closed curvature**. Graphite is flat sheets of sp² carbon. Diamond is sp³ carbon in a 3D lattice. Fullerenes introduce a third structural paradigm: closed polyhedral cages, where exactly 12 pentagons and a varying number of hexagons wrap the carbon lattice into a finite, hollow molecule. Every fullerene obeys Euler's formula for polyhedra — C60 has 60 vertices, 90 edges, and 32 faces (12 pentagons + 20 hexagons). The family includes: - C60 — Buckminsterfullerene, icosahedral, the canonical fullerene - C70 — the second-most-abundant natural fullerene, ellipsoidal - C76, C78, C82, C84 — higher "giant" fullerenes with multiple isomers - Endohedral fullerenes — fullerene cages with an atom trapped inside (e.g., La@C82, Sc3N@C80) - Functionalized derivatives — fullerenols, aminofullerenes, PCBM, dendrimer-fullerenes — where surface groups tune solubility and reactivity Fullerenes are distinct from [carbon nanotubes](/product-category/single-walled-carbon-nanotubes/), which extend the cage topology into a tube, and from [graphene](/product-category/cvd-graphene-films/), which is the infinite 2D sheet. All three share sp² carbon — they're topological cousins. ## 2. Structure and Symmetry **C60 structure:** Each of the 60 carbon atoms sits at the junction of two hexagons and one pentagon. No pentagon touches another pentagon — this is the **Isolated Pentagon Rule (IPR)**, which governs which fullerene cages are stable. The result is a molecule with full icosahedral (Iₕ) symmetry — the highest symmetry of any molecule. All 60 carbon atoms are chemically equivalent. **C70 structure:** C70 has 70 carbon atoms arranged in 12 pentagons and 25 hexagons. The shape is ellipsoidal, elongated along one axis — five additional hexagons form an equatorial belt. Symmetry drops from Iₕ to D5ₕ, and the 70 carbon atoms occupy five distinct chemical environments. **Bonding:** C60 has two bond lengths — a shorter "6-6" bond (1.38 Å, between two hexagons, more double-bond character) and a longer "6-5" bond (1.45 Å, between a hexagon and a pentagon, more single-bond character). This bond alternation has consequences for reactivity: the 6-6 bonds are preferential sites for cycloadditions. [image: ] ### Higher Fullerenes — Beyond C60 and C70 Higher fullerenes are lab-relevant but less widely used: - C76 exists as a single chiral D2 isomer — the first confirmed chiral fullerene. Research interest in molecular chirality and chiral electrochemistry. - C78 has multiple stable isomers (D3, C2v variants) — used to study isomer-specific optical and electronic properties. - C82 and C84 — the canonical hosts for endohedral metallofullerenes (e.g., La@C82, Sc3N@C80). Their larger cages accommodate metal atoms and clusters that won't fit inside C60. In arc-evaporated crude fullerene extract, C76–C84 typically represent 2–5% of the total fullerene fraction. Separating them from C60/C70 requires more HPLC stages than a C60/C70 separation, with yields of roughly 0.1–1% of starting soot. Pricing runs 10–50× the per-gram cost of C60. Most researchers only source higher fullerenes when the endohedral chemistry or a specific isomer property justifies the cost. [image: ] ## 3. Physical and Chemical Properties ### C60 properties | Property | Value | Molecular formula | C₆₀ | Molecular weight | 720.64 g/mol | Cage diameter (outer) | ~0.71 nm | Point group | Iₕ (icosahedral) | Bond lengths | 1.38 Å (6-6), 1.45 Å (6-5) | Density (solid, fcc) | 1.65 g/cm³ | Sublimation temperature | ~400 °C (vacuum) | Solubility in toluene | ~2.8 mg/mL at 25 °C | Solubility in CS₂ | ~7.9 mg/mL at 25 °C | Solubility in water | in situ* to form an azomethine ylide, which undergoes [3+2] cycloaddition across a 6-6 bond, yielding a pyrrolidine-fused fullerene. Prato reactions tolerate broader functional groups than Bingel and are the standard route to fullerene derivatives for biomedical use. **Regioselectivity** — monofunctionalization (one addition per cage) is usually straightforward, but multifunctionalization (2–6 additions per cage) raises selectivity questions. The "equatorial" and "polar" addition patterns of a bis-functionalized C60 have distinct electronic properties. Common derivatives: - PCBM / PC71BM — methano-fullerenes made by Bingel chemistry, workhorse OPV acceptors (see section 6.1) - Fullerenols (C₆₀(OH)ₙ, n = 20–40) — water-soluble, biocompatible, used in biomedical research - Aminofullerenes — C60-NH₂ and amino-pyrrolidine derivatives, used in drug delivery and antiviral research - Endohedral metallofullerenes — M@C2n where M is a lanthanide or early transition metal, plus tri-metallic nitride endohedrals (Sc3N@C80) - Fullerene dendrimers — used as scaffolds for controlled multivalent display of bioactive groups ## 8. Choosing the Right Purity Grade Not every application needs 99.9% purity. In 21 years of providing research-grade fullerenes, we've seen some customers pay for higher grades than they actually need, and others push 98% material through experiments where 99.9% would have achieved their desired results. We are always available to help guide our clients with fullerene selection. General guidance: - 95% purity — suitable for bulk exploratory work, composite additive research, and antioxidant formulations where trace C70 in C60 is acceptable. Cost-effective for gram-scale chemistry. - 98% purity — the workhorse grade for most OPV device fabrication, friction/lubrication studies, and photochemistry. Most published OPV device papers report C60 ≥ 98%. - 99% purity — required for quantitative photophysics (transient absorption, precise triplet yields), detailed electron-transfer kinetics, and device reliability studies where C70 trace contamination skews performance metrics. - 99.9% purity — demanded for OFET fabrication where carrier mobility is the headline number, endohedral metallofullerene synthesis (each chemistry step amplifies trace contaminants), NMR reference standards, and any work where sub-percent concentration effects matter. Practical rule: pick the grade where your bottleneck step starts dominating signal-to-noise. Higher purity doesn't help if your downstream chemistry or device fabrication reintroduces contaminants. ## 9. Solubility and Handling Practical notes for working with fullerenes: - Storage: Air-stable as dry powder. Solutions are UV-sensitive — amber glass, refrigerated, dark. - Solvent choice: Toluene, ortho-dichlorobenzene, and CS₂ are the workhorse solvents for native C60/C70. For functionalized derivatives, polarity tunes solubility: fullerenols are water-soluble, PCBM is moderately polar and dissolves in chlorobenzene + toluene. - Purity verification: HPLC is the reference — a research-grade C60 sample should show a dominant single peak with ≤ 1% area fraction from contaminants. Request the lot's HPLC chromatogram from your supplier if you don't receive one. - Safety: Acute toxicity of pure C60 is very low (LD50 > 2 g/kg in rodent models). Functionalized derivatives have variable profiles — consult the specific product's SDS. Standard nanomaterial handling applies: dust containment, nitrile gloves, lab coat, appropriate PPE. ## 10. Frequently Asked Questions ### What is the difference between a fullerene and a carbon nanotube? Both are sp² carbon cage structures, but fullerenes are finite, closed cages (C60, C70, etc.), while [carbon nanotubes](/product-category/single-walled-carbon-nanotubes/) extend the cage topology into a hollow tube — in principle infinitely long. A single-walled nanotube is effectively a "rolled-up" graphene sheet; a fullerene is a spherical-ish "rolled-up and closed" sheet. ### What is PCBM, and why is it used instead of raw C60? PCBM ([6,6]-phenyl-C₆₁-butyric acid methyl ester) is a C60 derivative with a methanofullerene sidegroup that dramatically increases solubility in common organic solvents (toluene, chlorobenzene). Raw C60 is poorly soluble in the solvents used for solution-processed OPV active layers, so PCBM is the practical workhorse. It's made by Bingel cyclopropanation of C60 with a methyl ester-substituted malonate. ### Can I use fullerenes for batteries? Research-only — C60 reversibly accepts up to 12 lithium atoms per molecule, but volumetric energy density is lower than graphite or silicon. Fullerenes are most relevant in battery research as model systems for studying electron-transfer kinetics, as additives in hybrid electrode formulations, or as templates for studying solid-electrolyte interphase (SEI) chemistry. ### Are fullerenes safe to handle? Pure C60 has very low acute toxicity in rodent studies (LD50 > 2 g/kg). Functionalized derivatives vary — always consult the specific product's SDS. Standard nanomaterial handling (dust containment, nitrile gloves, lab coat, appropriate PPE) applies. Our [Carbon Nanotube Safety Data Sheet](/carbon-nanotube-safety-data-sheet/) page has general nanomaterial safety context. ### How is fullerene purity measured? HPLC is the reference method — reverse-phase with toluene/hexane mobile phase, UV detection at 330 nm (C60) or 390 nm (C70). Supplementary techniques include ¹³C NMR (single peak for C60 at ~143 ppm), UV-Vis spectroscopy, MALDI mass spectrometry (clean C60⁺ at m/z 720), and IR spectroscopy (4 modes for pure C60). ### Why are endohedral metallofullerenes interesting? A metal atom (or small cluster) trapped inside the carbon cage is shielded from the chemical environment by the cage wall. This makes endohedrals promising as molecular qubits — the internal spin sees a much quieter magnetic environment than it would in a free ion. They're also of interest as MRI contrast agents and for studying atom-cage charge transfer. ### Where can I buy research-grade C60 and C70? Cheap Tubes supplies [research-grade C60 (99%+)](/product/carbon-fullerenes-c60/), [C70 (99%+)](/product/carbon-fullerenes-c70/), and [ultra-high purity C60 (99.9%)](/product/fullerenes-c60-99-9/) with TDS and SDS included on every order. See the [fullerenes product catalog](/product-category/fullerenes/) for current options and pricing. ## Related Reading - Solar Applications of Graphene — OPV and thin-film photovoltaic research with sp² carbon materials - Graphene Batteries: An Insider's Guide — how conjugated carbon materials are being engineered for energy storage - Carbon Nanotube Composites: Types, Properties & Uses — related sp² carbon architectures in composite formulations - Nanotechnology Glossary — terminology reference ## References Canonical literature on fullerenes: - Kroto, H. W.; Heath, J. R.; O'Brien, S. C.; Curl, R. F.; Smalley, R. E. Nature 1985, 318, 162. (original C60 discovery) - Krätschmer, W.; Lamb, L. D.; Fostiropoulos, K.; Huffman, D. R. Nature 1990, 347, 354. (arc-evaporation synthesis) - Hirsch, A.; Brettreich, M. Fullerenes: Chemistry and Reactions. Wiley-VCH, 2005. (textbook reference for chemistry) - Yu, G.; Gao, J.; Hummelen, J. C.; Wudl, F.; Heeger, A. J. Science 1995, 270, 1789. (first OPV bulk heterojunction) - Bingel, C. Chem. Ber. 1993, 126, 1957. (Bingel cyclopropanation) - Maggini, M.; Scorrano, G.; Prato, M. J. Am. Chem. Soc. 1993, 115, 9798. (Prato cycloaddition) - Yuan, J.; Zhang, Y.; Zhou, L.; et al. Joule 2019, 3, 1140. (Y6 NFA reference) ## Author **Mike Foley** founded Cheap Tubes Inc. in Townshend, Vermont in 2005 to supply researchers and R&D engineers with spec-guaranteed carbon nanotubes, graphene, and advanced nanomaterials. Over 21 years, Cheap Tubes has shipped research-grade materials to more than 10,000 customers, including research groups at MIT, NASA, Rice, Harvard, 3M, and the US Army. Mike has personally QC'd tens of thousands of fullerene orders and consults with OPV, lubrication, and biomedical labs on material selection. **Contact:** [Request a quote](/contact-cheap-tubes-inc/) | [sales@cheaptubes.com](mailto:sales@cheaptubes.com) --- ## Graphene Batteries: An Insider's Guide Source URL: https://www.cheaptubes.com/graphene-batteries-an-insiders-guide/ Last updated: 2026-04-24 --- Graphene Batteries - An Insiders Guide. Graphene Batteries are widely considered a "graphene's killer app". Killer apps drive commercial success and are critical for moving emerging technologies out of the lab and into large scale industrial applications. Savvy nanotech innovators and early adopters have adopted a collective mindset of "talk is cheap, now prove it works". Are batteries Graphene's killer app? Our [Graphene Battery User's Guide](https://www.cheaptubes.com/resources/graphene-battery-users-guide/)will detail traditional battery designs, emerging battery technologies, provide actionable steps that you can take to develop a graphene battery of your own, and detail what needs to happen to get advanced graphene batteries into consumer markets. [image: graphene-supercapacitor] ## We ♥ Graphene Batteries Humans love batteries - yes it sounds strange but batteries power our phones, tablets, laptops, cameras, fitbits, autos, toys, pacemakers, and clocks. Even the biggest companies with large market shares know they must be constantly advancing their battery's performance. Consumers want longer lasting batteries with faster charging times and we don't want to wait. As Samuel Gibbs astutely points out "The iPhone 7 is a missed opportunity. Apart from a bit of fluff retention the fit and finish, the cameras, fingerprint scanner, snappy performance and waterproofing are all great. But what does it matter how good it is when the battery is dead?" Ouch! While I'm fairly sure that Steve Jobs is still resting comfortably, Samuel is spot on in his assessment. [image: graphene-revolution-began-with-a-thought] The Graphene Revolution Began With A Single Idea Did Apple engineers simply take a pass when it came to designing the battery and matching it to the device's needs? I doubt it considering the risk to brand loyalty when selling devices between $650-$850 USD. A much loved company like Apple spends unfathomable sums of money designing & testing new products prior to launching them. Apple is aware that when they launch a new iphone, thousands of people line up to buy them as soon as they are released, much like when we used to sleep outside on the sidewalk while waiting for the ticket window to open for our favorite rock concerts. So what gives? Apple likely made a survey of commercially viable battery technologies and realized that a graphene battery wasn't ready for prime time for this generation iphone. Being an early adopter only works to your benefit if it doesn't create product nightmares. Imagine millions of phones with defective batteries. The cost alone would be staggering and the cost to brand loyalty devastating. Apple sure doesn't want [a Samsung like battery recall](https://www.bloomberg.com/news/articles/2016-09-18/samsung-crisis-began-in-rush-to-capitalize-on-uninspiring-iphone) on its hands. ## Graphene Battery Technology [image: Reduced graphene oxide rGO lithium battery electrode with 744 mAh/g capacity vs graphite] A battery is a source of electrical energy, which is provided by one or more electrochemical cells of the battery after conversion of stored chemical energy. In today’s life, batteries play an important part as many personal, household and industrial devices use batteries as their power source. In its most basic form, a battery is a cell consisting of an anode, a cathode, with an electrolytic material in between. There are 6 basic types of batteries. - Alkaline Batteries -Alkaline batteries are non-rechargeable, high energy density, batteries that have a long life span. This battery obtained its name because the electrolyte used in it is alkaline (potassium hydroxide). The chemical composition features zinc powder as an anode and manganese dioxide as the cathode with potassium hydroxide as the electrolyte. - Nickel Cadmium (NiCd)- mature and well understood but relatively low in energy density. The NiCd is used where long life, high discharge rate and economical price are important. Main applications are two-way radios, biomedical equipment, professional video cameras and power tools. The NiCd contains toxic metals and is environmentally unfriendly. - Nickel-Metal Hydride (NiMH) - has a higher energy density compared to the NiCd at the expense of reduced cycle life. NiMH contains no toxic metals. Applications include mobile phones and laptop computers. - Lead Acid — most economical for larger power applications where weight is of little concern. The lead acid battery is the preferred choice for hospital equipment, wheelchairs, emergency lighting and UPS systems. - Lithium Ion (Li‑ion) — fastest growing battery system. Li‑ion is used where high-energy density and lightweight is of prime importance. The technology is fragile and a protection circuit is required to assure safety. Applications include notebook computers and cellular phones. - Lithium Ion Polymer (Li‑ion polymer) — offers the attributes of the Li-ion in ultra-slim geometry and simplified packaging. Main applications are mobile phones. ## Why won't Li Ion Batteries just die? Li Ion batteries already have market acceptance. Companies have invested heavily production lines. Li Ion battery's improve performance a respectable 6-8% per year. Earlier this year, [an MIT start up announced they've doubled the life of a Li Ion battery](http://news.mit.edu/2016/lithium-metal-batteries-double-power-consumer-electronics-0817). Competing graphene alternatives, while promising are still likely years away from commercial acceptance. ## What's the holdup? As we've recently had Samsung's great example of an epic product battery fail, no one wants to responsible for that within their own organization, to let down their customers, and to have negative brand loyalty. Successful nano engineering takes repeated trials to make small steps in the right direction. It's not as easy as "throw some graphene in it and sell it". For an in depth review, check out our [Graphene Battery User's Guide](https://www.cheaptubes.com/resources/graphene-battery-users-guide/) to come up to date on research trends as well as to learn actionable steps that you can take to develop your own graphene battery with the four designs of experiments included in the guide. References [Types of Batteries and Their Applications (Bright Hub Engineering)](http://www.brighthubengineering.com/power-generation-distribution/123909-types-of-batteries-and-their-applications/) https://www.bloomberg.com/news/articles/2016-09-18/samsung-crisis-began-in-rush-to-capitalize-on-uninspiring-iphone http://news.mit.edu/2016/lithium-metal-batteries-double-power-consumer-electronics-0817 ### Source Graphene Materials for Battery Research We supply graphene oxide (for rGO anodes), graphene nanoplatelets (for composite cathodes), and SWCNTs (for conductive additives) to battery researchers and manufacturers. Bulk pricing, spec sheets, and technical guidance available. [Shop Graphene Oxide →](https://www.cheaptubes.com/product-category/graphene-oxide/)[Shop Graphene Nanoplatelets →](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- --- # Additional Content — Application Spotlights, Comparison Guides, Battery Hub > This appendix was added 2026-06-18. It indexes peer-reviewed research showcases (Application Spotlights), product-line comparison guides, and the battery applications content hub. See [/llms.txt](https://www.cheaptubes.com/llms.txt) for the concise URL index. --- ## About Mike Foley — Founder, Cheap Tubes Inc. Source URL: https://www.cheaptubes.com/about-cheap-tubes-inc/ Mike Foley founded Cheap Tubes Inc. in Brattleboro, Vermont, in 2005. The company has supplied research-grade carbon nanotubes, graphene, graphene oxide, MXene, and specialty nanomaterials to thousands of academic, government, and industrial laboratories worldwide. Cheap Tubes maintains an in-house technical sales process — every order is reviewed and supported by founder-level technical staff, not call-center reps. The company has shipped material that has been cited in peer-reviewed research across applications including lithium-ion batteries, supercapacitors, polymer composites, biomedical sensors, water purification membranes, electromagnetic shielding, thermoelectric generators, and structural concrete reinforcement. --- ## Materials in Peer-Reviewed Research Source URL: https://www.cheaptubes.com/cited-in-research/ Cheap Tubes maintains a public index of peer-reviewed studies that used its materials over the past two decades. The corpus includes hundreds of papers spanning carbon nanotubes (single-walled, double-walled, multi-walled, functionalized), graphene oxide, graphene nanoplatelets, fullerenes, and MXene. Citations appear in journals including Nature Communications, Advanced Materials, ACS Nano, Carbon, Energy & Environmental Science, Journal of Power Sources, and many others. The asset is curated as a public reference rather than a marketing claim — researchers can directly verify that material from Cheap Tubes has been used in the studies cited. --- ## Application Spotlights — Peer-Reviewed Research Showcases Each Application Spotlight summarizes a peer-reviewed paper that used Cheap Tubes material, identifies the specific product line, and links to the live page. See [/application-spotlights/](https://www.cheaptubes.com/application-spotlights/) for the full hub. --- ### MWCNT-1: Ethanol Dehydration Membrane (Gupta/Mitra, NJIT, Membranes 2022) Source URL: https://www.cheaptubes.com/mwcnt-pva-go-pervaporation-ethanol-dehydration-membrane-spotlight/ Paper: Gupta, A.; Mitra, S., *Membranes* (2022) Institution: NJIT (New Jersey Institute of Technology) Hero stat: **523:1 selectivity** Carboxyl-functionalized MWCNTs from Cheap Tubes were embedded into a hybrid PVA-GO-CNT-COOH pervaporation membrane that broke the ethanol-water azeotrope. The hydrophilic GO/COOH-MWCNT network selectively transports water while rejecting ethanol — achieving a 523:1 water/ethanol selectivity factor that surpasses commercial polyamide membranes by more than an order of magnitude. Cheap Tubes material cited: [Functionalized Multi Walled Carbon Nanotubes (COOH)](https://www.cheaptubes.com/product-category/functionalized-carbon-nanotubes/cooh-functionalized-carbon-nanotubes/) --- ### MWCNT-2: Flexible Printable Thermoelectric Generator (Mehmood, Brown + US Army CCDC, J Mater Sci 2020) Source URL: https://www.cheaptubes.com/mwcnt-flexible-printable-thermoelectric-generator-spotlight/ Paper: Mehmood, T. et al., *Journal of Materials Science* (2020) Institution: Brown University + US Army Combat Capabilities Development Command (CCDC) Hero stat: **13 mV at ΔT=20K** A printable hybrid rGO-MWCNT-PEDOT:PSS organic thermoelectric generator deposited on flexible polyimide substrate. The rGO+MWCNT scaffolding provides conductive pathways without sacrificing flexibility. The device generates 13 mV at ΔT=20K with cyclical bending durability — targeting wearable energy harvesting from body heat for portable electronics and self-powered sensors. NOTE: Cheap Tubes Industrial Grade MWCNTs are 90% pure, not the 70% figure occasionally cited in older specs. Cheap Tubes material cited: [Industrial Grade MWCNTs (10-30nm)](https://www.cheaptubes.com/product/multi-walled-carbon-nanotubes-90-10-30nm/) --- ### MWCNT-3: Room-Temperature Hydrogen Storage Composite (Desai, Wichita + UNAM, MRSE 2026) Source URL: https://www.cheaptubes.com/mwcnt-laceni-hydrogen-storage-polymer-composite-spotlight/ Paper: Desai, F. et al., *Materials for Renewable and Sustainable Energy* (2026) Institution: Wichita State University + UNAM (Mexico) Hero stat: **0.8 wt% H2 storage** A LaCeNi metal hydride composite with Graphitized MWCNT catalyst as the carbon framework. The Cheap Tubes Graphitized MWCNTs (99.5%+ purity, 8-15nm diameter) provide a sp2-conjugated carbon scaffold that improves hydrogen sorption kinetics in the metal hydride at near-ambient temperatures. The composite achieves 0.8 wt% reversible H2 storage at room temperature — a meaningful step toward practical mobile hydrogen storage for fuel cell vehicles. Cheap Tubes material cited: [Graphitized Multi Walled Carbon Nanotubes 99.5%+ 8-15nm](https://www.cheaptubes.com/product/graphitized-multi-walled-carbon-nanotubes-99-5-8-15nm/) --- ### MWCNT-4: Electrospun PAN/MWCNT Carbon Nanofibers (Yahya, University of Technology-Iraq, Iraqi J Sci 2026) Source URL: https://www.cheaptubes.com/mwcnt-electrospun-pan-carbon-nanofibers-graphitization-spotlight/ Paper: Yahya, R.A., *Iraqi Journal of Science* (2026) Institution: University of Technology — Iraq Hero stat: **1.9 S/cm conductivity** Electrospun polyacrylonitrile (PAN) fibers loaded with Industrial Grade MWCNTs and graphitized at lower temperature than conventional CNF processing. The Cheap Tubes IG MWCNTs (90% purity, 10-30nm diameter) act as graphitization templates inside the PAN matrix — enabling a lower-temperature, lower-cost route to electrically conductive carbon nanofibers. The composite reaches 1.9 S/cm conductivity, useful for fiber-based sensors, flexible heaters, and electrode mats. Cheap Tubes material cited: [Industrial Grade MWCNTs (10-30nm)](https://www.cheaptubes.com/product/multi-walled-carbon-nanotubes-90-10-30nm/) --- ### MWCNT-PURIFY: Bench-Scale Purification Methodology (Abbas et al., J Phys Conf Ser 2020) Source URL: https://www.cheaptubes.com/mwcnt-bench-purification-alcohol-h2o2-protocol-spotlight/ Paper: Abbas, M.S. et al., *Journal of Physics: Conference Series* (2020) Institution: University of Babylon (Iraq) Hero stat: **<0.6% impurity** A published bench-scale purification protocol for Cheap Tubes multi-walled carbon nanotubes using alcohol washing, H2O2 oxidation, and separation-funnel processing. The protocol takes off-the-shelf Industrial Grade MWCNTs and produces material with <0.6% residual impurities — equivalent to Cheap Tubes Standard or Graphitized lines without the upcharge. Useful as a Methodology Spotlight: researchers who need higher purity than 90% IG but want to control costs can publish their purification step rather than buying up to a higher SKU. Cheap Tubes material cited: [Industrial Grade MWCNTs](https://www.cheaptubes.com/product-category/multi-walled-carbon-nanotubes/) --- ### GO-1: rGO/ZnS Li-S Battery Cathode (Colombo et al., Politecnico Torino, Nanomaterials 2023) Source URL: https://www.cheaptubes.com/go-li-s-battery-rgo-zns-cathode-spotlight/ Paper: Colombo, A. et al., *Nanomaterials* (2023) Institution: Politecnico di Torino (Italy) Hero stat: **648 mAh/g capacity** Reduced graphene oxide (rGO) embedded with ZnS catalyst nanoparticles for a lithium-sulfur battery cathode. The rGO provides a conductive scaffold while ZnS catalytically suppresses the polysulfide shuttle effect that has historically plagued Li-S battery cycle life. The composite delivers 648 mAh/g specific capacity with markedly improved cycle stability — a step toward commercial Li-S batteries with 2x the energy density of Li-ion. Cheap Tubes material cited: [Reduced Graphene Oxide](https://www.cheaptubes.com/product/reduced-graphene-oxide/) --- ### GO-2: Dual-Anchor GO for CDI Desalination + CapMix Energy Harvesting (Pedico et al., Politecnico Torino 2022+2024) Source URL: https://www.cheaptubes.com/go-cdi-capmix-water-desalination-energy-harvesting-spotlight/ Paper: Pedico, A. et al., *Two papers (Energy Environ Sci + Desalination)* (2022 + 2024) Institution: Politecnico di Torino (Italy) Hero stat: **Same material, two applications** A single graphene oxide formulation — functionalized with dual anchor groups — used by the same lab in two distinct applications. Paper 1: capacitive deionization (CDI) electrodes for water desalination, achieving substantially improved salt removal capacity over standard activated carbon. Paper 2: CapMix (capacitive mixing) electrodes that harvest energy from salinity gradients at river-sea interfaces. Demonstrates that careful GO chemistry can serve both water purification and renewable energy applications. Cheap Tubes material cited: [Graphene Oxide Powder](https://www.cheaptubes.com/product/graphene-oxide-powder/) --- ### GO-3: 3D-Printed rGO + MnO2 Supercapacitor (Freyman, LLNL + UC Santa Cruz, Energy Adv 2026) Source URL: https://www.cheaptubes.com/go-3d-printed-rgo-supercapacitor-aerogel-spotlight/ Paper: Freyman, M.C. et al., *Energy Advances* (2026) Institution: Lawrence Livermore National Laboratory + UC Santa Cruz Hero stat: **1,370 F/g capacitance** Direct ink writing (DIW) of reduced graphene oxide aerogel scaffolds, post-loaded with MnO2 pseudocapacitive material. The 3D-printed architecture provides hierarchical porosity for ion transport while the rGO+MnO2 composition delivers both EDLC (electric double layer) and pseudocapacitance. Specific capacitance reaches 1,370 F/g — competitive with state-of-the-art bulk supercapacitor electrodes but with the geometric freedom of additive manufacturing for custom-form-factor energy storage. Cheap Tubes material cited: [Reduced Graphene Oxide](https://www.cheaptubes.com/product/reduced-graphene-oxide/) --- ### GO-4: CRISPR-Cas12a Sepsis Biosensor (Kasputis & Chen, Virginia Tech + UC Riverside, Anal Chem 2024) Source URL: https://www.cheaptubes.com/go-crispr-cas12a-sepsis-detection-biosensor-spotlight/ Paper: Kasputis, T.; Chen, J., *Analytical Chemistry* (2024) Institution: Virginia Tech + UC Riverside Hero stat: **3 × 10³ CFU/mL detection** Single-layer graphene oxide quenches a fluorescent ssDNA probe via π-π stacking. When the CRISPR-Cas12a complex detects bacterial DNA in a blood sample, its trans-cleavage activity releases the probe — restoring fluorescence. Detection limit reaches 3 × 10³ CFU/mL for sepsis-causing bacteria within minutes — versus 24-72 hours for traditional blood culture. The single-layer geometry is essential: only molecularly thin GO provides the right quenching efficiency for this fluorescence-on platform. Cheap Tubes material cited: [Single Layer Graphene Oxide](https://www.cheaptubes.com/product/single-layer-graphene-oxide/) --- ### GO-5: Sugar-to-Graphite via GO Catalytic Templating (Singh & Vander Wal, Penn State EMS, C 2022) Source URL: https://www.cheaptubes.com/go-catalyzed-sugar-graphitization-biomass-graphite-spotlight/ Paper: Singh, M.; Vander Wal, R.L., *C — Journal of Carbon Research* (2022) Institution: Penn State University, Earth and Mineral Sciences Hero stat: **Biomass → battery-grade graphite** Graphene oxide used as a catalytic templating agent to graphitize sucrose (table sugar) into battery-grade graphite at lower temperatures than conventional graphitization. The GO seed layer directs sp2 ordering in the developing graphitic structure, lowering the energy barrier for graphitization. The route is interesting commercially because it offers a sustainable, biomass-derived path to battery anode graphite — currently a Chinese-dominated supply chain — using domestic agricultural feedstock. Cheap Tubes material cited: [Graphene Oxide Powder](https://www.cheaptubes.com/product/graphene-oxide-powder/) --- ### GO-6: rGO/TiO2 DSSC Photoanode (Ghann et al., Coppin State + partners, ChemEngineering 2019) Source URL: https://www.cheaptubes.com/go-rgo-tio2-dssc-photoanode-solar-spotlight/ Paper: Ghann, W. et al., *ChemEngineering* (2019) Institution: Coppin State University + four partner institutions Hero stat: **+25% DSSC efficiency** In-house reduced graphene oxide combined with TiO2 nanoparticles as a dye-sensitized solar cell (DSSC) photoanode. The rGO improves electron transport in the TiO2 layer, reducing recombination losses. Result: 25% improvement in power conversion efficiency over baseline TiO2 DSSCs. Notable as a low-cost, low-temperature route to improved photovoltaic performance — DSSCs are particularly promising for indoor/diffuse-light applications where silicon underperforms. Cheap Tubes material cited: [Graphene Oxide Powder](https://www.cheaptubes.com/product/graphene-oxide-powder/) --- ### SWCNT-TCF: Ultra-Long SWCNT Transparent Conductive Films (Tai & Lubineau, Sci Rep 2016) Source URL: https://www.cheaptubes.com/ultra-long-swcnt-tcf-launch-spotlight/ Paper: Tai, K.; Lubineau, G., *Scientific Reports* (2016) Institution: KAUST (King Abdullah University of Science and Technology) Hero stat: **Ultra-long SWCNT TCFs** Long-aspect-ratio single-walled carbon nanotubes formed into transparent conductive films (TCFs) as a flexible alternative to ITO (indium tin oxide). The long-SWCNT network provides connected conductive pathways with fewer junction resistances than short-SWCNT or random-network films, enabling high transparency at low sheet resistance — the key metric for touchscreens, flexible displays, and electrochromic windows. Cheap Tubes material cited: [Single Walled Carbon Nanotubes 99%](https://www.cheaptubes.com/product/single-walled-carbon-nanotubes-99/) --- ### SWCNT Si-Anode: PPBT-SWCNT Composite (Gueon & Reichmanis, ACS AEM 2024) Source URL: https://www.cheaptubes.com/swcnt-ppbt-silicon-anode-spotlight/ Paper: Gueon, D.; Reichmanis, E., *ACS Applied Energy Materials* (2024) Institution: Lehigh University Hero stat: **High-cap Si Li-ion anode** Single-walled carbon nanotubes co-formulated with a PPBT (poly[3-(potassium-4-butanoate)thiophene]) conductive polymer to bind and connect silicon nanoparticles in a lithium-ion battery anode. The SWCNT network maintains electrical connectivity through silicon’s ~300% volume expansion during lithiation — addressing the central failure mode of Si anodes. Enables practical high-capacity Si anodes for next-generation Li-ion cells with significantly higher energy density than graphite. Cheap Tubes material cited: [Single Walled Carbon Nanotubes](https://www.cheaptubes.com/product-category/single-walled-carbon-nanotubes/) --- ### SWCNT EMI: Lightweight EMI Shielding Films (Yang et al., Carbon 2023) Source URL: https://www.cheaptubes.com/swcnt-emi-shielding-spotlight/ Paper: Yang, Y. et al., *Carbon* (2023) Institution: Beijing institutions Hero stat: **High-SE shielding film** Single-walled carbon nanotubes embedded into a lightweight polymer matrix to produce electromagnetic interference (EMI) shielding films. The SWCNT network provides high electrical conductivity at low loading (vs metals or carbon-black), and the resulting shielding effectiveness (SE) targets the X-band frequency range used in radar, 5G, and aerospace electronics. Critical advantage over metal shields: weight savings on the order of 10×. Cheap Tubes material cited: [Single Walled Carbon Nanotubes](https://www.cheaptubes.com/product-category/single-walled-carbon-nanotubes/) --- ### SWCNT-PEDOT TEG: Functionalized SWCNT Thermoelectric (Tonga et al., 2024) Source URL: https://www.cheaptubes.com/swcnt-pedot-pss-thermoelectric-spotlight/ Paper: Tonga, M. et al., *er.5535 (Energy Research)* (2024) Institution: University setting Hero stat: **Improved organic TEG** Functionalized single-walled carbon nanotubes blended with PEDOT:PSS conductive polymer for an organic thermoelectric generator (TEG). The chemical functionalization on the SWCNTs improves Seebeck coefficient by tuning the carrier concentration; the SWCNT network provides electrical conduction; PEDOT:PSS provides processability and flexibility. Result: an organic TEG capable of harvesting low-grade waste heat from skin, machinery, or industrial processes. Cheap Tubes material cited: [Functionalized Single Walled Carbon Nanotubes (COOH)](https://www.cheaptubes.com/product-category/functionalized-carbon-nanotubes/cooh-functionalized-carbon-nanotubes/) --- ### MWCNT-Canine: Smart Garment Respiration Sensor (Hong et al., ACS Sensors 2026) Source URL: https://www.cheaptubes.com/canine-respiration-mwcnt-smart-garment-spotlight/ Paper: Hong, S. et al., *ACS Sensors* (2026) Institution: Multi-institution Hero stat: **Canine respiration wearable** Multi-walled carbon nanotubes integrated into a flexible textile-based strain sensor sewn into a canine garment to monitor breathing rate. The MWCNT-coated fabric changes resistance as the dog’s chest expands during inhalation — providing wireless real-time respiration data for veterinary monitoring, working-dog stress assessment, and animal-research applications. Cheap Tubes material cited: [Multi Walled Carbon Nanotubes](https://www.cheaptubes.com/product-category/multi-walled-carbon-nanotubes/) --- ### MWCNT-Cement: Concrete Nanocomposite (Anastopoulos, J Compos Sci 2026) Source URL: https://www.cheaptubes.com/mwcnt-cement-nanocomposite-spotlight/ Paper: Anastopoulos, I., *Journal of Composites Science* (2026) Institution: Greek institution Hero stat: **Strength + durability gain** Multi-walled carbon nanotubes added to Portland cement at small loadings (typically 0.05-0.2 wt%) provide measurable improvements in compressive strength, flexural strength, and crack resistance. The MWCNTs nucleate C-S-H gel formation and bridge microcracks before they propagate. Applications include high-performance concrete for bridges, infrastructure, and structures requiring extended service life. Cheap Tubes material cited: [Multi Walled Carbon Nanotubes](https://www.cheaptubes.com/product-category/multi-walled-carbon-nanotubes/) --- ### GNP-1: Epoxy Fracture Toughness Enhancement Source URL: https://www.cheaptubes.com/gnp-epoxy-fracture-toughness-spotlight/ Paper: XG Sciences materials referenced, *Various journals* (Multiple) Institution: Multi-paper review Hero stat: **Toughness ↑ via GNP loading** Graphene nanoplatelets dispersed into epoxy resin systems improve fracture toughness, fatigue resistance, and impact performance at small loadings (0.1-1 wt%). The GNP platelets act as crack-deflectors and microcrack-bridgers, similar to how natural composites like nacre derive their toughness. Applications span aerospace structures, wind turbine blades, sporting goods, and high-performance automotive parts. Cheap Tubes material cited: [Graphene Nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ### GNP-Flexiphene: 1 wt% Flexiphene in PA66 (UMass Lowell Trial) Source URL: https://www.cheaptubes.com/flexiphene-pa66-umass-lowell-spotlight/ Paper: UMass Lowell Plastics Engineering, *Trial report* (2025) Institution: University of Massachusetts Lowell Hero stat: **1 wt% Flexiphene → PA66 gain** A 1 wt% loading of Flexiphene graphene nanoplatelets compounded into polyamide-66 (PA66) by UMass Lowell’s Plastics Engineering department. Mechanical testing showed meaningful improvements in tensile properties without sacrificing the inherent processability of PA66 — relevant for engineering plastics used in automotive under-hood components, electrical connectors, and load-bearing consumer products. Cheap Tubes material cited: [Flexiphene](https://www.cheaptubes.com/product/flexiphene/) --- ### GNP Fiber-Epoxy: Fatigue Life of Composite Laminates Source URL: https://www.cheaptubes.com/gnp-fiber-epoxy-fatigue-life-spotlight/ Paper: Multiple authors, *Composite-engineering journals* (Multiple) Institution: Multi-paper review Hero stat: **Fatigue life ↑** Graphene nanoplatelets incorporated into fiber-reinforced epoxy composite laminates (glass and carbon fiber) provide enhanced fatigue life and inter-laminar shear strength. The GNPs reside at the interlaminar region between plies, bridging the resin-rich zone where fatigue failures typically initiate. Particularly relevant for wind turbine blades (where fatigue life determines economic viability) and aerospace structures. Cheap Tubes material cited: [Graphene Nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ### GNP Concrete: Compressive Strength Enhancement Source URL: https://www.cheaptubes.com/gnp-concrete-compressive-strength-spotlight/ Paper: Multiple authors, *Construction journals* (Multiple) Institution: Multi-paper review Hero stat: **+12-25% compressive strength** Graphene nanoplatelets added to Portland cement composites at 0.05-0.1 wt% loading provide 12-25% improvements in compressive strength along with reduced water permeability and improved freeze-thaw resistance. The GNPs nucleate denser C-S-H gel formation and act as nano-scale aggregates. Targets include high-performance concrete for infrastructure with long service-life requirements. Cheap Tubes material cited: [Graphene Nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ### GNP Supercapacitor: Pulse-Power Electrode Source URL: https://www.cheaptubes.com/gnp-supercapacitor-pulse-power-spotlight/ Paper: Multiple authors, *Energy storage journals* (Multiple) Institution: Multi-paper review Hero stat: **Pulse-power EDLC** Graphene nanoplatelets formed into porous electrode films deliver high-rate (pulse-power) supercapacitor performance. The GNP morphology provides accessible surface area for ion adsorption with the conductivity needed for high current density. Applications include regenerative braking energy capture, power-tool starter assist, hybrid bus energy buffering, and grid-scale frequency regulation. Cheap Tubes material cited: [Graphene Nanoplatelets](https://www.cheaptubes.com/product-category/graphene-nanoplatelets/) --- ## Buying Decision Guides — Choosing Between Cheap Tubes Product Lines --- ## Which MWCNT Should You Buy? Industrial Grade vs Standard vs Graphitized — A Cheap Tubes Buying Decision Guide Source URL: https://www.cheaptubes.com/mwcnt-buying-guide-industrial-grade-vs-standard-vs-graphitized/ Buying Decision Guide · By Mike Foley , Founder, Cheap Tubes Inc. · Published: June 19, 2026 If you're shopping for multi-walled carbon nanotubes for the first time, the catalog can be confusing. Three different MWCNT product lines, prices that span an order of magnitude, purity numbers ranging from 90% to 99.5%+, and a half-dozen diameter SKUs in each line. The right answer depends entirely on what you're doing with the material. Using research-grade MWCNT for a percolation network in a polymer composite is overspending. Using industrial-grade MWCNT for a fuel cell electrocatalyst support is undershooting and your results will scatter. This guide walks through how to make the right call by application, with a side-by-side comparison and specific recommendations for the use cases we see most often. The Quick Answer If your application is... Polymer composites, EMI shielding, conductive coatings, cement reinforcement, antistatic films, electrode percolation networks → Industrial Grade MWCNT (90%) . Purity isn't the limiting factor; you're buying for mechanical and electrical percolation. Spending more for higher purity here is wasted money. General academic research, ink formulations, fiber spinning, hybrid material development, sensor substrates, supercapacitor electrode prep → Standard MWCNT (98%) . The workhorse line. Reproducible, research-grade, and the right purity tier for most published-paper work. Heterogeneous catalysis, biomedical applications, single-tube electronic devices, fuel cell electrocatalyst supports, hydrogen storage, defined-surface-chemistry sensors → Graphitized MWCNT (99.5%+) . When residual catalyst metals or amorphous carbon would compromise your results, the graphitization post-treatment eliminates both. The premium is worth it for these use cases. Side-by-Side Comparison Spec Industrial Grade Standard MWCNT Graphitized MWCNT Purity 90% 98% 99.5%+ Post-treatment As-synthesized (CVD) Purified to research grade Thermal graphitization (removes catalysts, converts amorphous carbon to graphitic structure) Diameter SKUs 10 nm, 10-30 nm, 20-40 nm 8 nm, 8-15 nm, 10-20 nm, 20 nm, 20-30 nm, 30-50 nm, 50 nm 8-15 nm, 10-20 nm, 20-30 nm, 30-50 nm, 50 nm Functionalization options Pristine (all diameters above) + COOH (10-30, 20-40 nm) + OH (10-30, 20-40 nm) Pristine (all 7 diameters above) + COOH (8/8-15/10-20/20/20-30/30-50/50 nm) + OH (8/8-15/10-20/20-30/30-50/50 nm) + NH2 (20 nm) + Short COOH + Short OH variants Pristine Graphitized (all 5 diameters above) + COOH-Graphitized (5 SKUs, 8-15 to 50 nm) + OH-Graphitized (5 SKUs, 8-15 to 50 nm) Catalyst residues Present (~10%) — Mo, Co, Fe typical Reduced (~2%) Largely eliminated (<0.5%) Amorphous carbon Present Reduced Converted to graphitic structure Raman I D /I G (typical) Higher (more defects) Mid-range Lowest (most graphitic) Price tier $ (lowest) $$ (mid) $$$ (premium) Best for Cost-sensitive composite + percolation work General research, papers, broad applications Catalysis, biomedical, high-purity electronics Industrial Grade MWCNT — When to Use, When Not To The Industrial Grade MWCNT line (90% purity) is the cost-effective tier. CVD-synthesized, minimally post-processed, available in 10 nm singular, 10-30 nm combined-range, and 20-40 nm diameter SKUs. The ~10% non-tube content is mostly residual catalyst metals (Mo, Co, Fe) from the CVD growth, plus some amorphous carbon and nano-capsule byproducts. Use it for: Polymer composite mechanical reinforcement (epoxy, PA66, PEEK, polyurethane) Conductive coatings and inks where percolation, not purity, drives performance EMI shielding films and ESD-protection coatings Cement and concrete nanocomposite reinforcement Antistatic textile coatings and yarn modification Battery electrode binder + conductive additive at scale Printable flexible electronics where cost per square meter dominates the engineering decision Educational lab work where students need bulk material to practice handling Don't use it for: Heterogeneous catalysis (residual Mo, Co, Fe will compete with engineered active sites) Biomedical applications where metal cytotoxicity matters Single-tube electronic device fabrication High-purity sensor electrodes with defined surface chemistry requirements Fuel cell electrocatalyst supports Published-research surface-chemistry work (you'll get scattered results) The decision rule: if the impurity load doesn't affect what you're measuring or what your product does, use industrial grade and save the cost premium for materials that actually matter to your performance. Standard MWCNT — The Research-Grade Workhorse The Standard MWCNT line (98% purity) is the broadest catalog by diameter range and the most commonly cited in peer-reviewed papers. Available in 8 nm, 8-15 nm, 10-20 nm, 20 nm, 20-30 nm, 30-50 nm, and 50 nm SKUs. Catalyst residues reduced to ~2%, amorphous-carbon content significantly lower than industrial grade, and reproducibility between lots good enough that controlled experiments produce clean results. Use it for: Academic research where reproducibility and clean characterization data matter Ink and dispersion formulations for printable electronics and inkjet work Carbon nanofiber spinning + electrospinning with PAN or other polymer precursors Hybrid composite material development (MWCNT/GO, MWCNT/polymer/metal hydride) Sensor substrate fabrication where surface chemistry is engineered post-purchase Supercapacitor electrode preparation at research scale Pre-functionalized COOH, OH, or NH2 work (broadest pre-functionalized catalog of any MWCNT line) Any application where the published-paper community uses "MWCNTs" without further spec Don't use it for: Pure cost-driven bulk composite applications (industrial grade is fine and cheaper) Catalysis where even 2% catalyst residue would skew your active-site measurements Biomedical applications where graphitized purity is the safety bar The decision rule: if you're publishing research, characterizing reproducibility, or doing controlled experiments where impurities would scatter results, Standard MWCNT is the right starting point. Graphitized MWCNT — The Premium Tier The Graphitized MWCNT line (99.5%+ purity) takes Standard MWCNT material and applies a high-temperature thermal treatment that vaporizes residual catalyst metals and converts amorphous carbon to graphitic structure. The result is a MWCNT with the lowest Raman I D /I G ratio in the catalog, minimal metal contamination, and the most ordered crystalline structure available off-the-shelf. Available in matched 8-15 nm, 10-20 nm, 20-30 nm, 30-50 nm, and 50 nm SKUs, plus pre-functionalized COOH and OH variants. Use it for: Heterogeneous catalysis where catalyst-metal residues would compete with engineered active sites (Pt, Pd, Au, transition-metal oxide supports) Fuel cell electrocatalyst supports (PEMFC, DMFC, AEMFC) Hydrogen storage composites where catalyst residues bias kinetics measurements Biomedical and biosensor applications where Mo/Co/Fe cytotoxicity matters Single-tube electronic devices where impurities create charge traps High-purity sensor electrodes with defined surface chemistry Photovoltaic and photoelectrochemical electrodes (clean charge transport) Aerospace and defense applications with stringent contamination specifications Don't use it for: Anything where Standard MWCNT would have worked (you're overspending without performance gain) Bulk composite filler applications (waste of premium material) The decision rule: if your application specifically requires the absence of catalyst residues or amorphous carbon (catalysis, biomedical, high-purity electronics), Graphitized MWCNT is the right choice and the cost premium is functional. Otherwise, you're paying for performance you can't use. Two Special Cases Worth Calling Out DIY purification of Industrial Grade or Standard MWCNT If you want higher purity than your starting tier but don't want to pay the Graphitized premium, you can purify in-house. A published 3-step alcohol + H 2 O 2 + separation-funnel protocol from a 2020 Iraqi research team drops impurities to <0.6% with <5% MWCNT mass loss. The full protocol takes 1-2 days of lab time per batch. Read the methodology Spotlight here . The economics work out when your lab time is cheap and your material cost is the constraint. Functionalized MWCNTs (COOH, OH, NH2) Every MWCNT line ships in both pristine and pre-functionalized variants — if your application needs functional groups (carboxyl, hydroxyl, or amine side groups) attached to the MWCNT sidewall, you don't need to DIY-functionalize unless you have a specialty chemistry requirement. The breadth of available functionalization differs by line: Standard MWCNT (98%) has the broadest functionalization catalog: COOH in 7 diameter SKUs (8, 8-15, 10-20, 20, 20-30, 30-50, 50 nm), OH in 6 SKUs (8, 8-15, 10-20, 20-30, 30-50, 50 nm), NH2 in 20 nm, plus Short COOH and Short OH variants in matched diameters for applications needing shorter aspect ratios. The Standard line is also the only line offering NH2 functionalization off the shelf. Industrial Grade (90%) offers COOH in 10-30 and 20-40 nm, OH in 10-30 and 20-40 nm. Lower per-gram cost; suitable when the functionalized MWCNT goes into a composite or bulk application where purity isn't the constraint. Graphitized MWCNT (99.5%+) offers COOH-Graphitized and OH-Graphitized each in 5 diameter SKUs (8-15, 10-20, 20-30, 30-50, 50 nm). The premium tier for catalysis, biomedical, and high-purity sensor work where pre-purified material is essential. DIY functionalization is still an option for groups with established surface-chemistry workflows or specialty group requirements (e.g., PEG, biotin, custom ligands) that we don't offer pre-attached. But for standard COOH, OH, or NH2 work, the pre-functionalized variants save you the lab time and give consistent batch-to-batch chemistry. Common Mistakes Researchers Make Buying Graphitized MWCNT for a polymer composite percolation network. The graphitization doesn't help your performance; you're paying for purity that doesn't change the percolation threshold or the bulk conductivity. Industrial Grade is the right call. Buying Industrial Grade MWCNT for a fuel cell electrocatalyst support. The ~10% catalyst-metal residues will skew your active-site composition and bias your performance measurements. Graphitized is essential. Buying Standard MWCNT for a published paper without specifying the lot. If you don't report the diameter, length, and purity grade in your Methods section, reviewers will ask. The Standard catalog has seven diameter SKUs — pick the right one and cite it explicitly. Mixing batches from different lots without re-characterizing. Even within a single product line, lot-to-lot variation matters for reproducibility. Order enough material upfront for your full experimental campaign. Defaulting to the cheapest option because your PI is cost-pressured. If you end up scattering data and re-running experiments because the impurity load contaminated your measurements, the cheaper material was the more expensive choice. Match purity to application. Browse the Three Lines $ Most affordable Industrial Grade MWCNT (90%) Composites, EMI shielding, conductive coatings, cement, antistatic films, bulk percolation networks. Browse Industrial Grade → $$ Research-grade Standard MWCNT (98%) Academic research, ink formulation, electrospinning, supercap electrodes, hybrid material R&D, DIY-functionalization precursor. Browse Standard MWCNT → $$$ Premium / pre-purified Graphitized MWCNT (99.5%+) Catalysis, biomedical, fuel cells, single-tube electronics, high-purity sensors, photovoltaic / photoelectrochemical electrodes. Browse Graphitized MWCNT → Frequently Asked Questions What's the actual difference between Industrial Grade, Standard, and Graphitized MWCNT? Three things differ: purity, post-treatment, and price. Industrial Grade is CVD-synthesized and minimally post-processed at 90% purity (the other 10% is residual catalyst metals plus amorphous carbon and nano-capsule byproducts). Standard MWCNT is purified to 98% research grade. Graphitized MWCNT takes the Standard material and applies a high-temperature thermal treatment that vaporizes catalyst metals and converts amorphous carbon to graphitic structure, reaching 99.5% plus purity. The three tiers price approximately at 1x / 2-3x / 5-10x of each other depending on diameter and quantity. How do I know which one I need? Ask whether impurities would affect your measurement or product performance. If you're building a polymer composite for mechanical reinforcement or electrical percolation, the 10% impurity load in Industrial Grade is invisible to your application — use it and save money. If you're doing catalysis where residual Mo, Co, or Fe would compete with your engineered active sites, you need Graphitized. If you're doing general academic research where reproducibility and clean characterization data matter, Standard MWCNT is the workhorse line. Can I just buy the cheapest one and purify it myself? Yes, if your lab time is cheap relative to material cost. A published 3-step alcohol plus H2O2 plus separation-funnel protocol drops Industrial Grade MWCNT impurities to less than 0.6 percent with less than 5 percent mass loss, taking 1 to 2 days per batch. This is the DIY-economics path. If your lab time is expensive or you need consistent batch-to-batch purity without your team running purification protocols, buy Graphitized. Do all three lines have the same diameter SKUs? No. Industrial Grade comes in 10 nm singular, 10-30 nm combined range, and 20-40 nm. Standard MWCNT has the broadest catalog: 8 nm, 8-15 nm, 10-20 nm, 20 nm, 20-30 nm, 30-50 nm, 50 nm. Graphitized MWCNT comes in 8-15 nm, 10-20 nm, 20-30 nm, 30-50 nm, 50 nm. Note that the 10-30 nm combined range is unique to Industrial Grade — if a paper cites that diameter, it identifies the IG line specifically. What about functionalized MWCNT (COOH, OH, NH2)? All three lines ship in both pristine and pre-functionalized variants. Pristine: every diameter SKU is available unfunctionalized in all three lines (Industrial Grade, Standard, Graphitized). Pre-functionalized: Standard MWCNT (98%) has the broadest catalog — COOH in 7 diameters, OH in 6 diameters, NH2 in 20 nm, plus Short COOH and Short OH variants. Industrial Grade offers COOH and OH in 10-30 and 20-40 nm. Graphitized offers COOH and OH in 5 diameter SKUs (8-15 to 50 nm). NH2 is only available in the Standard line. Will my paper's reviewers expect a specific grade? Reviewers will expect you to specify the diameter, length, purity, and supplier of any commercial MWCNT you used in your Methods section. For most academic research, Standard MWCNT at the appropriate diameter is the defensible choice and is widely cited in peer-reviewed literature. For catalysis, biomedical, or high-purity electronics work, reviewers will increasingly expect to see Graphitized or equivalent post-purified material justified in the Methods. For composite engineering papers, Industrial Grade is perfectly acceptable if the impurities don't affect what you're measuring. How do I cite Cheap Tubes products in a paper? Cite the specific SKU name (e.g., "Industrial Grade Multi Walled Carbon Nanotubes 10-30 nm, Cheap Tubes Inc., Grafton, VT, USA") along with the diameter, length, and purity grade. Use cheaptubes.com URLs in your bibliography if your journal accepts URL references. Reproducibility downstream depends on other researchers being able to source the same material. About the author Mike Foley is the founder of Cheap Tubes Inc. and CTI Materials. A high-tech manufacturing veteran with experience in semiconductor wafer fabs, thin-film optics, and nanotechnology, he holds a BS in Business Administration and two granted U.S. patents in nanoparticle dispersion , with additional patents pending in nanomaterials synthesis and applications. Cheap Tubes (Vermont, USA) has supplied research-grade carbon nanotubes, graphene, graphene oxide, MXene, and specialty nanomaterials since 2005 — used in thousands of peer-reviewed studies. See selected publications → About Mike Foley · Contact / Request a quote · All resources --- ## Which SWCNT Should You Buy? Purity, Length, Functionalization — A Cheap Tubes Buying Decision Guide Source URL: https://www.cheaptubes.com/swcnt-buying-guide-purity-length-functionalization/ Buying Decision Guide · By Mike Foley , Founder, Cheap Tubes Inc. · Published: June 19, 2026 Single-walled carbon nanotubes are more complicated to buy than multi-walled. SWCNT material varies along at least four axes — purity (60% to 99%+), length (short to ultra-long), functionalization (pristine, COOH, OH, NH2), and bundling (single-walled vs single-walled / double-walled mixed). The differences across those axes affect price by an order of magnitude and affect application performance by even more. Picking the right SWCNT for a transparent conductive film is a totally different decision than picking SWCNT for a polymer composite or a biosensor. This guide walks through how to make the call, with specific recommendations by application and the trade-offs at each tier. The Quick Answer by Application If your application is... Transparent conductive films (TCF), high-conductivity printed electronics, RF and microwave devices, single-tube spectroscopy → 99% purity, ultra-long . The flagship grade. The long aspect ratio + minimal junction resistance is what makes TCF work; anything less and the sheet conductivity collapses. General academic research, ink formulation, biosensor substrates, hybrid composite material development, electrochemistry, photovoltaic R&D → 95% purity (id=7757) or 90% SW-DW (id=154). The research-grade tier. Reproducible, defensible in published methods, broadly cited. Bulk polymer composites, EMI shielding, conductive coatings for paint or fabric, cost-sensitive composite reinforcement → 60% SW-DW (id=161). Cheapest SWCNT tier. Adequate for percolation work where purity isn't the limit. Biosensor functionalization, drug-delivery scaffolds, DNA/protein attachment, surface-chemistry-controlled electrode work → functionalized variants — pre-attached COOH, OH, or NH2 groups in the purity tier matched to your application. Polymer matrix inks, sprayable composites, dispersion-limited processing → short variants (1-4 nm length). Easier to disperse, less tangling during sonication, suitable for inkjet and spray-coat workflows. Side-by-Side Comparison — Pristine Purity Tiers Spec 60% SW-DW 90% SW-DW 95% SWCNT 99% Ultra-Long Purity 60% 90% 95% 99% Length Standard + Short variant Standard Standard Ultra-long (flagship spec) Tube structure SW + DW mixed SW + DW mixed SWCNT (predominantly single-walled) SW + DW mixed Functionalization options DIY only (or buy 99% functionalized variants) COOH, OH, NH2 (general SW-DW variants) DIY or use general SW-DW functionalized variants COOH-99 (id=152) Price tier $ (lowest) $$ $$$ $$$$ (premium) Best for Bulk composite percolation, EMI shielding, cost-driven applications General research, ink formulation, hybrid material work Defined-SWCNT research where SW vs DW matters, biosensors, electronics TCF, RF / microwave, high-conductivity printed electronics, premium R&D Product page SW-DW 60% (id=161) SW-DW 90% (id=154) SWCNT 95% (id=7757) SW-DW 99% Ultra-Long (id=148) The Four Purity Tiers — Detail 60% SW-DW — the cost tier SW-DW 60% (id=161) : CVD-synthesized, minimally post-processed. Mixed single-walled and double-walled tube population. The other 40% is amorphous carbon plus residual catalyst metals plus DWCNT fraction. Use it for bulk composite percolation, conductive coatings for paint or fabric, EMI shielding applications where impurity load doesn't affect performance. Don't use it for single-tube spectroscopy, biosensors, electronics that depend on defined surface chemistry, or any application where SW vs DW distinction matters. Short variant available: Short SW-DW 60% (id=163) — for ink and dispersion work where aspect ratio matters less than processability. 90% SW-DW — the workhorse research tier SW-DW 90% (id=154) : CVD synthesized with post-purification to research grade. Mixed SW + DW population. Cleaner than 60% by a meaningful margin; the 10% impurity is largely amorphous carbon with minimal catalyst residue. Use it for general academic research, ink formulation, hybrid material development (SWCNT/polymer, SWCNT/graphene, SWCNT/metal oxide), electrochemistry, photovoltaic R&D, sensor substrate prep. Don't use it for single-tube spectroscopy, applications requiring defined SWCNT-only composition, or premium electronics where ultra-long aspect ratio matters. 95% SWCNT — the defined-single-walled research tier SWCNT 95% (id=7757) : research-grade material specifically purified to predominantly single-walled composition (vs the SW-DW mixed populations at 60% and 90%). The distinction matters when your application sensitivity to tube structure (electronic band gap, chirality distribution, single-tube vs double-tube optoelectronic properties) is high. Use it for defined-SWCNT research, biosensor electrode work, electronics applications that depend on single-tube band-structure properties, electrochemistry where DWCNT contamination would skew results. Don't use it for bulk composite work where you're paying for purification you don't need. 99% SW-DW Ultra-Long — the flagship premium tier SW-DW 99% Ultra-Long (id=148) : the highest purity grade plus the longest tube length in the SWCNT catalog. Recently upgraded with a new ultra-long spec for transparent-conductive-film and RF/microwave applications where junction resistance between tubes dominates performance. Long tubes = fewer tube-to-tube contacts per unit area = lower sheet resistance for the same coverage. Use it for TCF for touchscreens and flexible displays, transparent EMI shielding, high-conductivity printed electronics, RF / microwave electronics, supercap electrodes where the conductivity matters more than the surface area, photovoltaic transparent electrodes, premium SWCNT research where reproducibility and lowest possible impurity load are essential. Don't use it for applications where 90% or 95% would have worked — you're paying the premium for ultra-long aspect ratio and 99% purity that doesn't affect your application. Pre-functionalized 99% variant available: COOH-99 (id=152) for ultra-pure carboxylated SWCNT work. Length — Standard vs Short Variants Most Cheap Tubes SWCNT ship in standard length (typical 5-30 μm for the SWCNT material). For applications where dispersion is the bottleneck (ink formulation, sprayable composites, polymer matrix mixing under shear), short variants (1-4 nm) are easier to disperse, less likely to tangle during sonication, and produce more uniform composite microstructure. Short SWCNT pay for processability with reduced aspect ratio, which lowers electrical percolation efficiency — the trade-off is application-dependent. Short pristine variants: Short SW-DW 60% (id=163) , Short SW-DW (id=157) (general grade) Short functionalized: Short COOH SW-DW 1-4 nm (id=231) , Short OH SW-DW 1-4 nm (id=217) Functionalization Options Pre-functionalized SWCNT variants save you the in-house surface chemistry workflow when your application needs COOH, OH, or NH2 groups attached to the SWCNT sidewall. Available across the SWCNT catalog: COOH SW-DW (id=156) — standard grade carboxylated SWCNT, general research COOH-99 SW-DW (id=152) — ultra-pure carboxylated for premium R&D OH SW-DW (id=155) — hydroxyl-functionalized SWCNT for hydrophilic dispersion + bioconjugation NH2 SW-DW (id=182) — amine-functionalized for protein attachment, drug delivery, biosensor coupling Short variants (1-4 nm): Short COOH SW-DW (id=231) , Short OH SW-DW (id=217) The COOH and OH functionalization is degree-controlled in production; if you need a specific degree-of-functionalization for your application, contact us for custom specifications. Specialty Products Thin Walled Carbon Nanotubes (id=379) — specialty grade between SWCNT and DWCNT, with controlled wall thickness for applications requiring intermediate electronic and mechanical properties. Common Mistakes Researchers Make Buying 99% Ultra-Long SWCNT for a polymer composite filler. The ultra-long aspect ratio doesn't help you in a sheared polymer composite; the tubes break during processing anyway, and you're paying the premium for a property you can't preserve. 60% or 90% is the right tier. Buying 60% SW-DW for biosensor work. The 40% impurity (including DWCNT fraction) will scramble your defined-surface chemistry. Spend the extra and buy 95% or functionalized variants. Not specifying the SW vs DW composition in published methods. Reviewers will ask. The 95% SWCNT product is "predominantly single-walled" by design; SW-DW products are mixed. Pick deliberately and cite explicitly. DIY-functionalizing 99% SWCNT when COOH-99 (id=152) ships pre-functionalized. Pre-functionalized variants save you the surface chemistry workflow and give consistent batch-to-batch degree of functionalization — buy the pre-functionalized SKU unless you need a specialty chemistry we don't offer. Ignoring length when ink formulation is the bottleneck. Short SWCNT variants (1-4 nm) disperse dramatically better than standard length and avoid the tangling that limits inkjet and spray-coat workflows. The aspect-ratio trade-off is small relative to the processing benefit. Browse the SWCNT Catalog $ Most affordable 60% SW-DW SWCNT Bulk composites, EMI shielding, conductive coatings, cost-sensitive percolation work. SW-DW 60% → $$ Workhorse research 90% SW-DW SWCNT General academic research, ink formulation, hybrid material work, electrochemistry, PV R&D. SW-DW 90% → $$$ Defined SW-only 95% SWCNT Defined-SWCNT research, biosensors, electronics where SW vs DW matters. SWCNT 95% → $$$$ Flagship premium 99% SW-DW Ultra-Long TCF, RF / microwave, high-conductivity printed electronics, premium R&D. SW-DW 99% → Or Browse by Category All single-walled and double-walled carbon nanotubes, plus functionalized variants and specialty products. All SWCNT → Functionalized CNTs → Frequently Asked Questions What's the difference between SWCNT, SW-DW, and DWCNT? Single-walled carbon nanotubes (SWCNT) are individual tubes formed from a single rolled graphene sheet. Double-walled (DWCNT) have two concentric tubes. SW-DW mixed products contain both populations because CVD synthesis without specialized chirality purification produces both. The 95% SWCNT product is predominantly single-walled by design; the 60%, 90%, and 99% products are SW-DW mixed. The distinction matters when your application is sensitive to band-structure properties or single-tube optoelectronics. How do I pick between 60%, 90%, 95%, and 99% purity? Match purity to what your measurement or application is sensitive to. For bulk percolation, EMI shielding, or composite mechanical reinforcement: 60% is fine. For general academic research and ink formulation: 90% SW-DW is the workhorse. For applications where SW vs DW distinction matters or where electronic band-structure properties are central: 95% SWCNT (predominantly single-walled by design). For TCF, RF and microwave electronics, premium high-conductivity work: 99% Ultra-Long. Why does the 99% product have the "Ultra-Long" tag? Long SWCNT have fewer tube-to-tube junction contacts per unit area than short SWCNT. For applications like transparent conductive films, RF and microwave devices, and high-conductivity printed electronics, junction resistance between tubes dominates the overall sheet conductivity. Ultra-long tubes produce dramatically lower sheet resistance at the same coverage density. The 99% Ultra-Long product is specifically engineered for those applications. What about Short SWCNT variants? Short SWCNT (1-4 nm) sacrifice aspect ratio for processability. Easier to disperse, less tangling during sonication, more uniform composite microstructure. The trade-off is reduced electrical percolation efficiency. Use short variants when dispersion is the bottleneck (inkjet, spray-coat, polymer matrix mixing under shear). Use standard length when percolation efficiency matters more than processability. Are functionalized SWCNT pre-attached or do I DIY-functionalize? Cheap Tubes ships pre-functionalized SWCNT variants in COOH, OH, and NH2 forms — no DIY needed for standard chemistry. Pre-functionalized variants include COOH SW-DW (id=156), OH SW-DW (id=155), NH2 SW-DW (id=182), COOH-99 SW-DW (id=152), Short COOH SW-DW (id=231), Short OH SW-DW (id=217). DIY-functionalize only if you need specialty chemistry (PEG, biotin, custom ligands) we don't offer pre-attached. How do I cite Cheap Tubes SWCNT in a paper? Cite the specific product (e.g., "Single Walled-Double Walled Carbon Nanotubes 99 Ultra-Long, Cheap Tubes Inc., Grafton, VT, USA") along with the purity, length, and functionalization (if any). Use cheaptubes.com URLs in your bibliography if your journal accepts URL references. Reproducibility downstream depends on other researchers being able to source the same material. About the author Mike Foley is the founder of Cheap Tubes Inc. and CTI Materials. A high-tech manufacturing veteran with experience in semiconductor wafer fabs, thin-film optics, and nanotechnology, he holds a BS in Business Administration and two granted U.S. patents in nanoparticle dispersion , with additional patents pending in nanomaterials synthesis and applications. Cheap Tubes (Vermont, USA) has supplied research-grade carbon nanotubes, graphene, graphene oxide, MXene, and specialty nanomaterials since 2005 — used in thousands of peer-reviewed studies. See selected publications → About Mike Foley · Contact / Request a quote · All resources --- ## Graphene & CNT Battery Applications — Hub + Spokes --- ## Graphene and Carbon Nanotube Battery Applications Source URL: https://www.cheaptubes.com/graphene-cnt-battery-applications/ By Mike Foley , Founder, Cheap Tubes Inc. & CTI Materials LLC — 21 years supplying carbon nanomaterials to battery R&D and production. TL;DR Multi-walled carbon nanotubes (MWCNT) are now the dominant conductive additive in lithium-ion cathode formulations, replacing carbon black at one-fifth the loading. Graphene and silicon-graphene composites address the cycling failure mode of high-capacity silicon anodes. Graphene, reduced graphene oxide, and MXene serve as high-surface-area electrodes in supercapacitors and pseudocapacitors. Carbon nanotube and graphene scaffolds enable next-generation lithium-sulfur and lithium-air R&D by trapping polysulfide intermediates and accommodating volumetric changes. This guide maps each major battery application to the right carbon nanomaterial, the specifications that matter, and where to source them at research, pilot, and production scale. Quick selection table: Battery problem Material Cheaptubes category Cathode conductivity (LFP, NMC, LCO) MWCNT 95–98%, 8–20 nm OD Industrial CNT Silicon anode expansion buffer MWCNT 99%+, GNP, rGO SWCNT , GNP Supercapacitor electrode GNP, rGO, MXene Ti 3 C 2 T x GNP , Graphene Oxide , MXene Li-S polysulfide host Porous CNT, GO scaffolds SWCNT 99% , Graphene Oxide Dispersion bottleneck (any application) Surfactant-stabilized formulations Flexiphene technology Start with the battery problem you are solving and follow the tree to the right carbon nanomaterial grade and loading. Why carbon nanomaterials matter in batteries Three properties drive the role of carbon nanotubes and graphene in modern battery design: Electrical conductivity. Single-walled carbon nanotubes carry current along their axis at metallic conductivity (10 5 –10 6 S/m for individual SWCNT). Even imperfect MWCNT bundles deliver 100–10,000× the conductivity of carbon black at equivalent mass loading. This translates directly into higher rate capability and lower internal resistance. Surface area. A single layer of graphene has a theoretical surface area of 2,630 m²/g — every carbon atom is a surface atom. Graphene oxide, reduced graphene oxide, and MXene Ti 3 C 2 T x achieve experimentally accessible surface areas of 200–700 m²/g, which is the substrate every supercapacitor and pseudocapacitor needs to maximize stored charge. Mechanical strength and flexibility. Carbon nanotubes have tensile strengths 50–100× that of high-strength steel at one-sixth the density. A flexible carbon network around a brittle active material like silicon or sulfur absorbs the volumetric strain that would otherwise pulverize the electrode after a few hundred cycles. These three properties are why every major lithium-ion cell manufacturer has either adopted or actively qualified carbon nanotubes as a conductive additive in cathodes, and why graphene composites dominate the silicon-anode patent landscape from 2018 forward. Where each carbon nanomaterial operates in a modern battery cell — from cathode through supercapacitor and next-generation chemistries. The four application categories Battery applications for carbon nanomaterials fall into four working categories. Each has a different dominant material, a different maturity level, and a different set of specifications you need to get right. 1. Cathode conductive additive (commercial production) MWCNT replacing carbon black in LFP, NMC, and LCO cathode formulations. Loadings of 0.3–1.5 wt% CNT achieve the same percolation network as 2–5 wt% carbon black, freeing 1.5–4 percentage points of mass for active material. This is the largest commercial CNT-in-battery application today by tonnage. → Read more: CNT as Cathode Conductive Additive — LFP, NMC, LCO 2. Silicon-carbon anode composites (pilot and early production) Silicon's theoretical capacity (4,200 mAh/g) is roughly ten times that of conventional graphite anodes, but its 300% volume expansion during lithiation pulverizes the electrode within the first few cycles. CNT and graphene matrices buffer this expansion mechanically while providing the electrical highway the disconnected silicon fragments would otherwise lose. Several major battery makers have shipped Si-C anode cells in 2024–2026. → Read more: Silicon-CNT & Graphene Lithium-Ion Anodes 3. Supercapacitor and pseudocapacitor electrodes (commercial) Graphene nanoplatelets, reduced graphene oxide, and MXene serve as high-surface-area conductive substrates in EDLCs and pseudocapacitors. MXene contributes both double-layer capacitance and surface-redox pseudocapacitance, achieving volumetric capacitances above 1,500 F/cm³ in optimized films. Commercial supercapacitor manufacturers have shipped graphene-based devices since 2016. → Read more: Graphene & MXene Supercapacitor Electrodes 4. Next-generation chemistries: Li-S, Li-air, solid-state (R&D) Carbon nanotube and graphene scaffolds are the dominant cathode host architecture in lithium-sulfur cell research, where porous carbon traps soluble polysulfide intermediates that would otherwise shuttle between electrodes. Lithium-air and solid-state battery R&D similarly leverage carbon nanostructures for catalysis and interfacial conduction. Commercial deployment is 2027+ for most of these chemistries. → Read more: CNT & Graphene in Li-S, Li-air, and Solid-State Batteries Materials × applications: which spec for which problem The same nanomaterial label hides a wide range of grades. A 95% MWCNT optimized for industrial cathode slurry is different from a 99.9% MWCNT used in academic Si-anode research. Here is the practical selection matrix: Material Cathode additive Si anode Supercapacitor Li-S / next-gen Typical loading Notes SWCNT 95% Specialty ✓ – ✓ 0.05–0.5 wt% Best aspect ratio, premium price SWCNT 99% – ✓ – ✓ (R&D) 0.05–0.5 wt% R&D-grade, excellent for paper publication MWCNT 8–20 nm, 95% ✓✓✓ – – – 0.3–1.5 wt% Cathode workhorse — best price/performance MWCNT 8–20 nm, 98% ✓✓ ✓ – – 0.3–1.5 wt% Cleaner cathode, anode-friendly MWCNT 99.9% – ✓ – ✓ 0.5–2 wt% Academic R&D, ultra-low metal residual GNP (graphene nanoplatelets) – ✓ ✓✓ ✓ 1–10 wt% Anode buffer, supercap conductive backbone GO (graphene oxide) – – ✓ ✓✓ 1–10 wt% Polysulfide trapping via oxygen groups rGO (reduced graphene oxide) – ✓ ✓✓ ✓ 1–10 wt% Conductivity restored, defect-stabilized MXene Ti 3 C 2 T x – – ✓✓✓ – 5–80 wt% (electrode) Pseudocapacitive, premium price ✓ = useful · ✓✓ = strong fit · ✓✓✓ = dominant choice Materials × applications fit matrix. Darker color indicates stronger application fit; color codes the primary application category. The most common selection mistake is pulling the highest-purity or highest-spec material when the application doesn't require it. A 99.9% MWCNT in a cathode slurry adds cost without measurable performance benefit — the binder, electrolyte interface, and cell-level engineering will dominate any gain. Save the high-purity grades for fundamental R&D where metal residuals would interfere with measurement. Procurement realities — research, pilot, and production scale Most published battery papers use grams to tens of grams of carbon material. Most production cells use kilograms to tonnes per year. The supply chain considerations differ at every step. Research scale (mg to ~10 g): Purity, characterization data, and lot-to-lot reproducibility matter more than price. Buy what your method requires, document the lot number, and accept the per-gram premium. Pilot scale (10 g to 1 kg): Dispersion behavior becomes the dominant variable. Two MWCNT lots with the same nominal spec can disperse very differently in NMP, water, or your specific binder system. Source from a supplier who will provide pre-dispersed slurries or surfactant-stabilized formulations and who can talk through dispersion strategy. This is where tools like the Flexiphene patented surfactant technology earn their keep — the dispersion problem alone wastes more pilot batches than any other failure mode. Production scale (kg to tonne): Price, lead time, COA reproducibility, and packaging logistics dominate. Lock in a supplier who can deliver in your packaging spec (drum, super-sack, IBC), with a reproducible COA per lot, and who has the capacity to scale with you. The right supplier should be running quality control on every lot — TGA for ash content, BET for surface area, Raman for graphitization quality, TEM for diameter and length distribution. Cheap Tubes Inc. covers all three scales. Researchers can buy 1 g samples; pilot teams can buy 100 g–10 kg with characterization data; production buyers can negotiate tonnage contracts with consistent COA and packaging. Three procurement tiers — what matters at each scale and how Cheap Tubes supports every step. Working with hard-to-disperse materials Single-walled CNT, the highest-aspect-ratio multi-walled CNT, and many graphene grades are notoriously difficult to disperse uniformly. Bundling, agglomeration, and re-aggregation in slurries are the most common failure modes in battery R&D and the most expensive failure mode in production scale-up. Three approaches to manage dispersion in battery applications: Aggressive mechanical processing — high-shear mixing, ultrasonication, three-roll milling. Effective but consumes energy, can damage long tubes (cutting them shorter and reducing aspect ratio), and rarely scales cleanly. Functionalization — chemical attachment of -COOH, -OH, or -NH 2 groups to the carbon surface improves polar-solvent compatibility. Useful for water-based systems but can degrade conductivity if over-functionalized. Cheap Tubes' functionalized MWCNT category covers the major functional group options. Surfactant-stabilized formulations — non-covalent dispersion using engineered surfactants. Preserves the carbon's electrical and mechanical properties while delivering a stable dispersion that can be loaded into cathode slurries, anode pastes, or supercapacitor electrode coatings without re-bundling. The Flexiphene patented surfactant system developed by CTI Materials addresses this category specifically — NASA validation and 100× lower interfacial resistance vs comparable non-stabilized formulations make it the strongest commercial option for battery dispersion at scale. Free sample request available at the link. For lab batches, options 1 and 2 typically suffice. For pilot or production scale, option 3 is the only approach that consistently delivers reproducible electrode coatings without per-batch re-engineering. Patent-protected polymer-nanocarbon composite formulations The challenge in moving battery composites from R&D to production is not the carbon material itself — it is the polymer matrix that must hold the carbon dispersed, conduct ions or electrons, and survive thousands of charge cycles without degradation. The battery industry is migrating away from legacy PVDF binders toward a defined set of polymer systems: polyimide for silicon anodes, polyamide and water-soluble polyamide variants for cathodes, polyaniline and polyaminotriazole as conductive coatings, nylon for separators, and polyester-based films for solid-state architectures. CTI Materials holds patent coverage ( U.S. Patents 10,049,783 and 11,961,630 ) on polymer-nanocarbon composite formulations specifically combining CNT, graphene, graphene oxide, and graphene nanoplatelets with these exact polymers — nylon, polyester, polyimide, polyamide, polyaminotriazole, and polyaniline. The Flexiphene patented surfactant technology delivers stable dispersions in each of these polymer matrices, with NASA-validated performance data (100× lower interfacial resistance, 96× higher capacitance, +19% polymer strength at 1 wt% loading). For battery R&D and production teams, this means a single sourcing relationship covers both the carbon nanomaterials and the patent-protected polymer-composite formulations — eliminating the integration risk of stitching together suppliers across the composite stack. For licensees and OEMs developing proprietary chemistries, the patent portfolio provides freedom-to-operate options for the polymer systems most likely to scale in lithium-ion, silicon-anode, supercapacitor, and solid-state battery production. Request a Flexiphene technical sample → The battery industry is migrating from PVDF to next-generation polymers — all six target polymers are covered by CTI Materials patents on CNT and graphene composites. Authoritative external references Yoo, E. et al. — graphene nanosheets as LIB anode active material delivering 540 mAh/g vs graphite's 372 mAh/g (foundational, 2008) ( Nano Letters ) Chou, S.-L. et al. — first Si/graphene composite anode demonstrating 1168 mAh/g over 30 cycles (2010) ( Electrochem. Commun. ) Ji, L. et al. — graphene oxide as sulfur immobilizer in high-performance Li/S cells, foundational paper for GO trapping (2011) ( JACS ) Lukatskaya, M. R. et al. — MXene for high-power supercapacitors (2013) ( Science ) Raccichini, R. et al. — comprehensive review of graphene/GO/rGO in batteries and electrochemical capacitors (2015) ( Nature Materials ) Bonaccorso, F. et al. — graphene for batteries, supercapacitors and beyond (2016) ( Nature Reviews Materials ) Tang, J., Pang, J. & Wang, J. — covalent 3D CNT@rGO nano-hybrid for high-efficiency LiFePO 4 cathodes (2025) ( Advanced Science ) Tong, X. et al. — comprehensive review of CNT applications in lithium-ion batteries (2025) ( Carbon Energy ) DOE Office of Electricity — Energy Storage Grand Challenge Roadmap (External links reflect representative peer-reviewed literature; no endorsement implied.) Frequently asked questions Why use carbon nanotubes instead of carbon black in cathodes? Carbon nanotubes form a percolation network at far lower mass loading than spherical carbon black particles because of their high aspect ratio. Typical industrial cathodes use 2–5 wt% carbon black; equivalent percolation is achieved with 0.3–1.5 wt% MWCNT. The mass freed by lower additive loading is added back as active material, raising cell-level energy density by 1–4%. What loading of MWCNT is typical in LFP cathodes? Most production LFP formulations use 0.5–1.0 wt% MWCNT as the sole conductive additive, or 0.2–0.5 wt% MWCNT combined with a reduced carbon-black fraction. The exact loading depends on cathode coating thickness, target rate capability, and binder system. Higher MWCNT loadings improve rate capability but at a cost premium. Can SWCNT replace MWCNT for cathode conductive additive? Technically yes — SWCNT achieves percolation at even lower loading (0.05–0.2 wt%) — but the per-gram cost difference (5–20× higher) means most production cells stay with MWCNT. SWCNT in cathodes appears in premium niche products and high-rate cells where the conductivity gain justifies the cost. What's the role of graphene in silicon anodes? Graphene serves three functions simultaneously in silicon anode composites: a flexible mechanical buffer that absorbs the 300% volume expansion of silicon during lithiation; an electrical conductor that maintains contact with silicon fragments after they crack; and a structural matrix that limits the SEI growth which would otherwise consume electrolyte cycle after cycle. Why MXene for supercapacitors and not lithium-ion batteries? MXene's high pseudocapacitive contribution and excellent in-plane conductivity are well-matched to charge/discharge timescales of seconds (supercapacitors). At lithium-ion timescales (minutes to hours of charge/discharge), MXene's low gravimetric capacity vs lithium intercalation materials means it can't compete with graphite or silicon as a primary anode material. MXene's role in lithium chemistry is mostly as a conductive scaffold or interlayer rather than the active material. Are functionalized CNTs needed for batteries? For most cathode and anode applications, pristine MWCNT or SWCNT performs better than functionalized variants — the functional groups disrupt the conjugated π-network that delivers the electrical conductivity benefit. Functionalized CNT is most useful when dispersion in a polar solvent (especially water) is a hard requirement and you cannot use a surfactant approach. For polysulfide trapping in Li-S, the oxygen groups on graphene oxide are an exception — they actively bind polysulfide species, which is exactly the desired behavior. What dispersion methods work best for battery slurries? Lab scale: ultrasonic horn or bath sonication for short dispersions (5–30 minutes), with mechanical stirring during slurry homogenization. Pilot scale: high-shear mixers (e.g., IKA, Silverson), three-roll mill for high-viscosity slurries, planetary ball mills for solid-state cathode preparation. Production scale: in-line high-shear mixing combined with surfactant-stabilized pre-dispersions to skip the most variable steps. How to scale from lab grams to production kilograms? Three rules: (1) lock the specification — diameter range, length range, purity, and ash content must stay within tight bounds across orders; (2) use the same dispersion approach at every scale, even if mechanical method changes — surfactant-stabilized pre-dispersions are the most scale-stable; (3) validate at each step — do not skip from 100 g to 10 kg without an intermediate batch. Cheap Tubes provides matched lots at each scale to minimize lot-to-lot variation as you scale. Get started For specific battery application categories, start with one of the dedicated guides above. --- ## Carbon Nanotubes as Cathode Conductive Additive — LFP, NMC, and LCO Source URL: https://www.cheaptubes.com/cnt-cathode-conductive-additive-batteries/ By Mike Foley , Founder, Cheap Tubes Inc. & CTI Materials LLC. Part of the Graphene & CNT Battery Applications hub. TL;DR Multi-walled carbon nanotubes (MWCNT) have become the preferred conductive additive in lithium iron phosphate (LFP) and nickel-manganese-cobalt (NMC) cathodes for lithium-ion cells. At 0.3–1.5 wt% loading they deliver the same percolation network that 2–5 wt% carbon black provides — freeing up to 4 percentage points of mass for active material and raising cell-level energy density by 1–4%. The right grade is typically MWCNT 8–20 nm outer diameter, 95–98% purity, dispersed via surfactant or high-shear pre-mixing into NMP or aqueous binder systems. This page covers the mechanism, the LFP/NMC/LCO selection differences, and the specifications that determine performance and reproducibility. The problem with carbon black For three decades, the standard conductive additive in lithium-ion cathodes has been carbon black — typically Super P, Ketjen Black, or similar acetylene-black variants. Carbon black is cheap, well-characterized, and easy to disperse. Its limitation is geometry: carbon black particles are spheres of 30–60 nm diameter that conduct only between adjacent particles. Building a continuous electrical network through a thick cathode coating requires a percolating chain of touching spheres — which in turn requires a high mass loading, typically 2–5 wt% of the cathode formulation. That 2–5 wt% comes out of the active-material budget. Every percentage point allocated to carbon black is a percentage point not contributing to capacity. In a thick LFP cathode targeting 200 mAh/g of active-material capacity, displacing 4 wt% carbon black with 1 wt% conductive additive reclaims 3 wt% of mass for additional active material — directly raising cell-level energy density. The second problem with carbon black is its rate-capability ceiling. Spherical particle networks have many junction points, each a contact-resistance bottleneck. At high charge or discharge rates, the voltage drop across these junctions limits how fast the cell can deliver power. Cells targeting fast-charging consumer applications, electric-vehicle high-power discharge, or grid frequency response benefit from a conductive additive that minimizes the number of junctions in the current path. These two limitations — mass burden and junction resistance — are exactly the problems carbon nanotubes solve. Why MWCNT works as a cathode conductive additive A multi-walled carbon nanotube has an aspect ratio (length / diameter) typically between 100 and 10,000. A single 10 µm MWCNT 15 nm in diameter spans an entire cathode coating in one continuous conducting path. Where carbon black requires hundreds of touching spheres to bridge a cathode, a single CNT bridges it directly with zero internal junctions. Percolation threshold. Classical percolation theory predicts that anisotropic conductive fillers — long thin objects like nanotubes or fibers — reach a connected network at a critical volume fraction inversely proportional to their aspect ratio. For spherical particles, percolation requires roughly 16 vol%. For nanotubes with aspect ratio 1,000, percolation can be achieved at 0.05 vol% or lower. Translated into mass: where carbon black needs 2–5 wt% to percolate, MWCNT needs 0.3–1.5 wt%. This 3–10× reduction in conductive-additive mass is the fundamental commercial driver. Junction reduction. Beyond mass savings, the long-tube geometry eliminates the multi-junction resistance ladder of a sphere network. Most current paths through a cathode loaded with MWCNT cross only one or two tubes, vs hundreds of carbon-black-particle contacts. The result is lower internal resistance, higher rate capability, and reduced heating during fast charging. Mechanical reinforcement. Carbon nanotubes also provide mechanical reinforcement to the cathode coating during cycling. Cathode active materials such as NMC undergo small but cumulative volume changes during lithiation and delithiation. The CNT network reduces the cracking and electrical disconnection that otherwise progressively degrade cycle life — a secondary but measurable benefit, especially in high-nickel NMC formulations. The combination of lower mass loading, lower junction resistance, and mechanical reinforcement is why production cell manufacturers have either adopted MWCNT or actively qualified it across all major cathode chemistries. Same conductive network — carbon black needs hundreds of sphere junctions while MWCNT bridges with single tubes at 3-10× lower mass loading. LFP vs NMC vs LCO — application-specific considerations The right MWCNT grade and loading vary by cathode chemistry. Lithium iron phosphate (LFP). LFP has intrinsically low electronic conductivity (~10 -9 S/cm), making it the chemistry that benefits most from a high-conductivity additive. MWCNT loadings of 0.5–1.5 wt% are typical in commercial LFP formulations. LFP-cell makers — particularly those targeting energy-storage-system (ESS) and entry-tier electric vehicle applications — have led the industrial adoption of CNT in cathodes. Combination strategies (low CNT + reduced carbon-black fraction) are also common in cost-sensitive LFP cells. Nickel-manganese-cobalt (NMC) and high-nickel variants. NMC has higher intrinsic conductivity than LFP, so the conductivity benefit of CNT is smaller — but the mechanical reinforcement benefit is larger because NMC undergoes more volume change per cycle. Typical loadings are 0.3–1.0 wt% MWCNT. High-nickel NMC (NMC811, NMC9-series) particularly benefits from CNT because the mechanical-reinforcement effect mitigates the rapid cycle-life decay of high-nickel chemistries. Lithium cobalt oxide (LCO). LCO retains a niche in consumer electronics requiring high volumetric energy density. CNT is used in some premium LCO cells primarily for the mass-saving benefit; loadings of 0.3–0.8 wt% are typical. For all three chemistries, the CNT specification range converges: 8–20 nm outer diameter, 5–20 µm length, 95–98% purity. The differences are loading and the relative emphasis on conductivity vs mechanical benefits. Typical MWCNT loading versus legacy carbon black baseline across LFP, NMC, NMC811, and LCO production cathode formulations. Material specifications that matter For a cathode conductive additive, four MWCNT specifications determine the working performance: Outer diameter (8–20 nm). Smaller-diameter MWCNT has higher aspect ratio and percolates at lower loading, but is harder to disperse and more expensive to produce. Larger-diameter MWCNT (20–50 nm) is easier to handle but loses some of the percolation benefit. The 8–20 nm range is the practical sweet spot for cost-performance balance in production cells. Length (5–20 µm). Longer tubes improve percolation efficiency but are more prone to entanglement and bundling. Shorter tubes (1–5 µm) disperse more easily but require slightly higher loading. Most commercial cathode formulations target 10–15 µm average length. Note that aggressive sonication or ball milling during dispersion can cut tubes shorter — this is a meaningful effect in pilot scale-up. Purity (95–98%). Carbonaceous purity above 95% is essential — non-carbon impurities (catalyst metal residues, amorphous carbon) can create local hot spots, increase internal cell impedance, or contribute to side reactions at the cathode interface. For most production LFP and NMC, 95–98% MWCNT is sufficient. Premium and high-rate cells use 99%+. R&D and academic studies often specify 99.9% to eliminate metal-residue interference with measurement. Dispersion behavior. This is the most under-appreciated specification. Two MWCNT lots with identical nominal specs (same diameter, length, and purity) can disperse very differently into the same NMP or water-based binder system. Dispersion behavior depends on the manufacturing CVD conditions, the post-processing (acid treatment, annealing, surface treatment), and the bundling state of the as-produced material. The most reliable strategy is to pre-disperse MWCNT in a surfactant-stabilized formulation rather than disperse from dry powder — this is exactly the gap that the Flexiphene patented surfactant technology addresses for production-scale dispersion. A useful rule: if your dispersion takes more than 30 minutes of high-shear processing per batch to look uniform, the dispersion failure mode will dominate your batch-to-batch variability long before the MWCNT specification does. Four MWCNT specifications determine cathode performance — outer diameter, length, purity, and dispersion strategy. Patent-protected polymer binders. A growing share of production cathode formulations is migrating from PVDF/NMP binder systems to water-based polyamide or polyamide-blended binders, and to polyimide binders for high-temperature applications. CTI Materials holds patent coverage ( U.S. Patents 10,049,783 and 11,961,630 ) on CNT + graphene/GO/GNP composites with polyamide, polyimide, polyaniline, polyaminotriazole, nylon, and polyester polymer matrices — the exact binder chemistries the cathode industry is adopting. For production buyers transitioning to these next-generation binders, the Flexiphene patented system provides both the dispersion technology and freedom-to-operate on the polymer-composite chemistry. Three MWCNT dispersion approaches — only surfactant-stabilized Flexiphene formulations scale cleanly to production. Practical formulation guidance A representative starting formulation for an LFP cathode: Component Loading (wt%) Notes LFP active material 95.5–96.5 Carbon-coated LFP particles, 0.5–2 µm MWCNT (8–15 nm, 95%) 0.5–1.0 Pre-dispersed in NMP or surfactant-stabilized aqueous Carbon black (Super P or equivalent) 0–1.5 Optional; 0.5 wt% common in cost-tuned formulations PVDF binder 1.5–2.5 NMP solvent system Solvent (NMP) to slurry viscosity Typically 60–70% solids in slurry For a high-nickel NMC811 cathode the loading shifts: Component Loading (wt%) NMC811 active material 96.5–97.5 MWCNT (8–15 nm, 98%) 0.3–0.8 Carbon black 0–1.0 PVDF binder 1.5–2.0 The exact loading depends on coating thickness, current density target, and binder system. The ranges above are commercial-reference points, not absolute optima — every formulation requires validation on the target cell format and chemistry. Representative LFP and high-nickel NMC811 cathode slurry formulations — production reference compositions. Cheaptubes products for cathode conductive additive applications Industrial-Grade MWCNT — production-scale MWCNT in 8–20 nm OD, 95–98% purity. Available by the kilogram and tonnage. Ships in customer-spec packaging (drums, super-sacks). CNT Composite Additive — dedicated SKU optimized for conductive-additive applications, with characterization data tuned for percolation performance. CNT Masterbatches — pre-dispersed concentrates in PA6, PC, ABS, PP, and other engineering polymers for direct loading into cathode binder systems. Multi-Walled Carbon Nanotubes (full catalog) — for R&D and pilot work requiring specific OD, length, or purity grades not available in the industrial line. Flexiphene surfactant-stabilized dispersions — for dispersion-limited production scale-up. NASA-validated, U.S. patented, free sample request available for qualifying applications. For custom MWCNT specifications (specific OD distribution, length cuts, surface treatment), or for tonnage supply contracts, contact Cheap Tubes Inc. directly — the standard catalog covers ~85 SKUs but custom production runs are available for production buyers. Authoritative external references Tang, J., Pang, J. & Wang, J. — covalent 3D CNT@rGO nano-hybrid for high-efficiency LiFePO 4 cathode conductivity, current commercial-relevance state-of-the-art (2025) ( Advanced Science ) Tong, X. et al. — comprehensive review of CNT applications in lithium-ion batteries including freestanding anodes, conductive additives, and current collectors (2025) ( Carbon Energy ) Hassoun, J. et al. — full LIB cell with graphene anode + LiFePO 4 cathode achieving 190 Wh/kg energy density (2014) ( Nano Letters ) Su, F.-Y. et al. — single-walled CNT as a conducting additive for LFP cathodes (2011) ( Carbon ) Sehrawat, P. et al. — review of CNT-based composite cathode materials for lithium-ion batteries (2022) ( Energy Reports ) DOE Office of Vehicle Technologies — battery cell engineering Annual Merit Review presentations (External links reflect representative peer-reviewed literature; no endorsement implied.) Frequently asked questions What's the typical MWCNT loading in a commercial LFP cathode? 0.5–1.0 wt% as the sole conductive additive, or 0.2–0.5 wt% MWCNT combined with 0.5–1.5 wt% carbon black. The exact loading depends on coating thickness, target rate capability, and the LFP particle morphology. Cost-optimized formulations often use the combined approach because residual carbon black is cheaper than equivalent CNT mass. Can SWCNT replace MWCNT in cathodes? Technically yes — SWCNT achieves percolation at 0.05–0.2 wt%, even lower than MWCNT — but the per-gram cost of SWCNT is 5–20× higher. SWCNT in cathodes appears in premium niche cells (e.g., high-rate consumer or aerospace applications) where the conductivity-per-gram advantage justifies the cost premium. For mainstream LFP and NMC production, MWCNT remains the better cost-performance choice. What MWCNT diameter is best for LFP cathodes? 8–15 nm outer diameter is the typical commercial sweet spot. Smaller diameters (5–8 nm) reach percolation at lower loading but are harder to disperse and more expensive. Larger diameters (20–50 nm) are easier to handle but require slightly higher loading. Is MWCNT compatible with both NMP and aqueous (water-based) binder systems? Yes, with caveats. NMP-based PVDF binder systems are the legacy standard and disperse pristine MWCNT readily with high-shear mixing. Water-based binder systems (CMC/SBR) are increasingly popular for cost and environmental reasons but require either a surfactant-stabilized MWCNT dispersion or functionalized MWCNT to disperse uniformly. Surfactant-stabilized formulations like Flexiphene are particularly well-suited to aqueous cathode systems. Does MWCNT replace carbon black entirely or only partially? Both approaches are used in production. Full replacement (MWCNT only, 0.5–1.5 wt%) maximizes the energy-density gain but requires the most careful dispersion control. Partial replacement (MWCNT 0.2–0.5 wt% + carbon black 0.5–1.5 wt%) is more forgiving in production and achieves most of the energy-density benefit. Cost-tuned formulations often favor partial replacement; energy-density-tuned formulations favor full replacement. Continue reading Hub: Graphene & CNT Battery Applications — overview and material selection across all four battery application categories Spoke 2: Silicon-CNT and Graphene Lithium-Ion Anodes Spoke 3: Graphene & MXene Supercapacitor Electrodes Spoke 4: CNT & Graphene in Li-S, Li-air, and Solid-State Batteries Buying guide: Multi-Walled Carbon Nanotubes Buying Guide About the author Mike Foley is the founder of Cheap Tubes Inc. and CTI Materials LLC. He holds 2 granted U.S. patents (10,049,783 and 11,961,630) in carbon nanomaterial applications, with additional patents in prosecution. His patented materials were selected by NASA for the Enceladus mission as a dual-capacitance layer in ion-selective electrodes. Mike has supplied carbon nanomaterials to battery R&D and production for 21 years. --- ## Silicon-CNT and Graphene Composites for Lithium-Ion Anodes Source URL: https://www.cheaptubes.com/silicon-cnt-graphene-lithium-ion-anode/ By Mike Foley , Founder, Cheap Tubes Inc. & CTI Materials LLC. Part of the Graphene & CNT Battery Applications hub. TL;DR Silicon has roughly ten times the theoretical specific capacity of graphite (4,200 mAh/g vs 372 mAh/g) but expands by approximately 300% during lithiation, pulverizing pure-silicon anodes within a few cycles. Carbon nanotubes and graphene composites address this failure mode through three complementary mechanisms: mechanical strain absorption, electrical conductivity restoration after particle cracking, and SEI stabilization. Production cells with silicon-carbon anodes have shipped since 2024, with target capacity gains of 20–40% at the cell level vs graphite. The polymer binder chemistry (polyimide and polyamide families) is migrating in parallel with the carbon-material selection, and CTI Materials' Flexiphene patent portfolio ( U.S. Patents 10,049,783 and 11,961,630 ) covers exactly these polymer-nanocarbon composite formulations. This page covers design strategies, material-grade selection, and procurement considerations for silicon-CNT and silicon-graphene anode composites. The silicon anode capacity vs cycling problem Lithium intercalation into graphite forms LiC 6 — one lithium for every six carbons, a theoretical capacity of 372 mAh/g. Lithium alloying with silicon forms Li 15 Si 4 at room temperature (or Li 22 Si 5 at elevated temperatures) — between 3.75 and 4.4 lithium atoms per silicon, a theoretical capacity of 3,580–4,200 mAh/g depending on alloy phase. At the cell level, replacing graphite with silicon could in principle deliver 20–40% higher energy density at the same cell mass. The barrier is mechanical. Silicon expands volumetrically by roughly 300% during full lithiation (and contracts back during delithiation). Pure silicon particles experience this strain at the particle scale on every cycle. The first few cycles crack the particles into smaller fragments; subsequent cycles continue the process; within 50–200 cycles, the silicon has pulverized to the point that electrical contact between fragments — and between the silicon and the current collector — is lost. Capacity drops to a fraction of the initial value. A second failure mode compounds the first. The newly exposed silicon surfaces formed by each crack consume electrolyte to grow new solid-electrolyte interphase (SEI) layers. SEI growth is irreversible — every new layer permanently removes lithium and electrolyte from the cell's available pool. After enough cycles, the SEI growth consumes so much lithium that the cell cannot deliver capacity even where particles remain electrically connected. Together, the volume-expansion problem and the SEI-growth problem make pure silicon anodes commercially impractical. Carbon nanostructures address both. Three states show why silicon anodes need carbon: pristine, lithiated and pulverized, then Si-C composite buffered to 80%+ retention. How CNT and graphene solve the expansion problem Three mechanisms operate simultaneously when CNT or graphene is incorporated into a silicon anode composite: 1. Mechanical strain absorption. A flexible carbon matrix around silicon particles accommodates the 300% volume change without cracking. Carbon nanotubes have tensile strengths 50–100× that of high-strength steel at one-sixth the density. A web of MWCNT around a silicon particle stretches and rebounds with each lithiation cycle, redistributing the strain across the network rather than concentrating it at the silicon surface. Graphene nanoplatelets and reduced graphene oxide perform a similar function with sheet-like geometry — the silicon expands into the spaces between graphene layers, with the layers sliding past each other to accommodate the change. 2. Electrical conductivity preservation. Even with mechanical buffering, silicon fragments still form during cycling. The decisive question for cycle life is whether the fragments stay electrically connected to the rest of the electrode. Carbon nanotubes act as an electrical highway through the composite — a single 10 µm MWCNT spans dozens of silicon particle diameters and bridges any cracks that develop. Without this electrical network, silicon fragments become electrochemically dead and capacity drops irreversibly. 3. SEI stabilization. A confined silicon particle inside a graphene shell or CNT cage exposes far less surface area to the electrolyte than a free silicon particle. The SEI forms primarily on the carbon outer surface, which is relatively stable once formed. New silicon surface created by internal cracking is shielded from the electrolyte by the carbon shell — preventing the runaway SEI growth that would otherwise consume electrolyte and lithium. The performance impact is dramatic. Published data on Si-graphene and Si-MWCNT composites shows capacity retention above 80% after 500 cycles at moderate (C/2) rates, compared to <40% retention for unmodified silicon anodes. The best Si-C composite architectures achieve over 1,500 mAh/g at the composite level (still 4× the capacity of graphite) with cycle lives suitable for commercial deployment. Hybrid Si-CNT-graphene composites maintain 86% capacity at 300 cycles vs pure silicon's 40% at 200 cycles. Composite architectures Silicon-carbon anode composites fall into four practical design families: Si@graphene core-shell. Silicon particles or nanowires encapsulated in a graphene or rGO shell. The shell mechanically constrains expansion and stabilizes the SEI on the carbon outer surface. Commercial implementations typically use 5–15 wt% graphene with silicon nanoparticles in the 50–200 nm range. Si-CNT yarn or network. Silicon particles dispersed within a CNT scaffold. The CNT network provides both mechanical buffering and the conductive backbone. Optimized formulations use 5–15 wt% MWCNT with silicon particles in the 100–500 nm range. SWCNT is sometimes preferred for the highest conductivity at the lowest mass loading. Si-rGO sandwich. Silicon particles between sheets of reduced graphene oxide. The rGO sheets slide past each other during expansion, accommodating strain while maintaining a conductive network. Common loadings: 10–30 wt% rGO. Hybrid Si-CNT-graphene composites. The current state-of-the-art combines all three carbon morphologies — graphene sheets, MWCNT bridges, and amorphous carbon coating — around silicon nanoparticles. Each carbon form addresses a different failure mode. These architectures appear most often in current commercial production cells targeting 20–40% capacity gain over graphite. The right architecture depends on the silicon morphology (nanoparticle, nanowire, porous), the binder system, and the cell-level targets. Most commercial Si-anode designs use a hybrid approach in production. Four composite architectures for silicon anodes - hybrid Si-CNT-graphene is the production state-of-the-art. Material specifications that matter For silicon-anode composite work, the carbon material selection depends on application stage: Graphene nanoplatelets (GNP). Thickness 5–15 nm, lateral size 5–25 µm. The workhorse for Si-graphene sandwich and shell architectures. Loadings 5–30 wt% of total anode mass. Cheap Tubes' GNP catalog covers the major lateral size and thickness combinations used in commercial anode work. Reduced graphene oxide (rGO). Defect-stabilized, conductive, easy to disperse from GO precursor. Lateral size typically 0.5–5 µm. Common loadings 10–30 wt%. Available via the graphene oxide category — most rGO research starts with GO from the same supplier to control the reduction step in-house. SWCNT 95–99% purity. Best mechanical reinforcement and lowest-mass percolation. Diameters 1–2 nm, lengths 5–30 µm. Loadings as low as 0.5–3 wt% for the conductivity backbone. Premium price but justified in high-spec cells. Available in Cheap Tubes' SWCNT catalog . MWCNT 8–20 nm, 98%+ purity. Cost-effective alternative to SWCNT for the conductive backbone. Loadings 1–5 wt%. The 98%+ purity grade is important for anode applications — metal residuals in lower-purity MWCNT can promote unwanted side reactions at the lithium-rich anode interface. Dispersion strategy. The dispersion problem at the anode interface is acute. Silicon particles, carbon, and binder must form a uniform composite without phase separation. For pilot and production scale, surfactant-stabilized dispersions perform better than dry-mixed formulations — the Flexiphene patented system was originally validated on this class of dispersion and remains the strongest commercial option for surfactant-stabilized silicon-carbon anode formulations. Patent-protected polymer binder coverage for Si-anode composites. The silicon-anode industry is moving from PVDF binders to polyimide and polyamide binder systems that better tolerate silicon volume expansion. Polyimide binders preserve adhesion through repeated 300% volumetric strain cycles where PVDF would crack and delaminate. CTI Materials holds patent coverage ( U.S. Patents 10,049,783 and 11,961,630 ) on CNT + graphene/GO/GNP composites with polyimide, polyamide, polyaniline, polyaminotriazole, nylon, and polyester matrices — covering the exact next-generation binder chemistries the silicon anode industry is adopting. For Si-anode R&D and pilot teams qualifying these binder systems, the Flexiphene patented dispersion technology provides validated performance data and freedom-to-operate on the composite chemistry. The 2024 Tark & Lee work (Korea Electrotechnology Research Institute) demonstrates the importance of this combined approach — dispersant-free N-doped SWCNT + graphene encapsulation of silicon, achieving accelerated Li-ion transport and improved cycle stability. The dispersion engineering and polymer-binder selection are inseparable from the carbon-material specification when scaling Si-C anodes to production. Carbon material selection matrix for silicon anode composites - GNP, rGO, SWCNT, MWCNT, functionalized CNT, and patented Flexiphene dispersions. Cheaptubes products for silicon-anode applications Graphene Nanoplatelets — multiple lateral sizes and thicknesses suitable for Si-graphene shells and sandwich structures Graphene Oxide / Reduced Graphene Oxide — for rGO-based sandwich architectures Single-Walled Carbon Nanotubes — 95% to 99.9% purity grades for premium and R&D anode work Multi-Walled Carbon Nanotubes — 98%+ purity for cost-effective conductive backbone Functionalized CNT — -COOH, -OH, -NH 2 functional groups for water-based binder compatibility Flexiphene surfactant-stabilized dispersions — for scale-up of silicon-carbon anode slurry where dispersion uniformity drives yield. NASA-validated, free sample request available. For custom silicon-carbon formulations or tonnage supply, contact Cheap Tubes Inc. directly . PVDF cracks under 300% Si expansion; polyimide flexes and survives - the silicon anode industry is migrating to polyimide binders. Authoritative external references Chou, S.-L. et al. — first Si/graphene composite anode demonstrating 1168 mAh/g stable over 30 cycles, foundational paper (2010) ( Electrochem. Commun. ) Ng, S.H. et al. — Si nanoparticles–graphene paper composite achieving >2200 mAh/g over 50 cycles (2010) ( Chem. Commun. ) Magasinski, A. et al. — silicon-graphene composite anodes (2010) ( Nature Materials ) Chan, C. K. et al. — silicon nanowire anodes (2008) ( Nature Nanotechnology ) Wu, H. et al. — stable silicon-graphene hybrid anodes (2013) ( Nature Communications ) Tark, H.J. & Lee, D.G. — dispersant-free colloidal engineering of Si-nanocarbon hybrid anode using N-doped SWCNT + graphene encapsulation, accelerated Li-ion transport (2024) ( Advanced Functional Materials ) Recent comprehensive review — CNT and graphene for relieving volume expansion in Si-based composite anodes (2024) ( Carbon , 218, 118726 ) Tailoring rGO sheet size for Si@rGO composite anodes (2024) ( ACS Appl. Mater. Interfaces ) DOE Vehicle Technologies — Si anode roadmap ( Annual Merit Reviews ) (External links reflect representative peer-reviewed literature; no endorsement implied.) Frequently asked questions Why does silicon need carbon at all — why not pure Si nanoparticles? Pure silicon nanoparticles cycle better than micron-scale silicon (because smaller particles tolerate strain), but they still suffer from SEI runaway growth and electrical disconnection after enough cycles. The carbon network is what extends cycle life from a few dozen cycles to several hundred and ultimately several thousand cycles needed for commercial cells. What silicon loading is typical in commercial Si-C anodes? Most commercial Si-C anode chemistries use 5–20 wt% silicon in a graphite-dominant matrix. Some next-gen designs push to 30–40% silicon. Pure silicon anodes (>80% Si) remain primarily R&D. Is SWCNT necessary or is MWCNT sufficient? For most commercial Si-C anode formulations MWCNT (98%+, 8–20 nm) delivers excellent performance at significantly lower cost. SWCNT is favored in premium cells, fast-charge applications, and academic R&D where the highest conductivity and best mechanical reinforcement at lowest mass justify the premium price. What's the difference between GO, rGO, and graphene in Si anodes? Graphene (GNP, mechanically exfoliated, CVD) has the highest electrical conductivity but is hardest to disperse. Graphene oxide (GO) has oxygen functional groups that improve dispersion in polar solvents but reduce conductivity — useful as a precursor. Reduced graphene oxide (rGO) restores most of the conductivity while keeping useful surface defects that anchor silicon particles. Most Si-anode work uses rGO as the practical compromise; pure CVD graphene is reserved for fundamental studies. How does the carbon affect first-cycle coulombic efficiency? First-cycle coulombic efficiency (CE 1 ) is critical for Si-anode cells because every percentage point of irreversible capacity loss in the anode requires extra cathode material to compensate. Pristine silicon CE 1 is typically 60–80%. Si-C composites with well-engineered SEI stabilization achieve 85–92% CE 1 — close to but still below graphite's 92–95%. Composite design and pre-lithiation strategies (chemical or electrochemical) are active development areas for closing this gap. Continue reading Hub: Graphene & CNT Battery Applications Previous spoke: CNT Cathode Conductive Additive Next spoke: Graphene & MXene Supercapacitor Electrodes Buying guides: SWCNT , MWCNT , Graphene Nanoplatelets About the author Mike Foley is the founder of Cheap Tubes Inc. and CTI Materials LLC. He holds 2 granted U.S. patents (10,049,783 and 11,961,630) in carbon nanomaterial applications, with additional patents in prosecution. His patented materials were selected by NASA for the Enceladus mission as a dual-capacitance layer in ion-selective electrodes. Mike has supplied carbon nanomaterials to battery R&D and production for 21 years. Application Spotlight: PPBT/SWCNT Stress-Relieving Coating Delivers 1,894 mAh/g on Silicon Microparticle Anodes — Gueon, Ren, Sun et al. (Reichmanis group, Lehigh + Brookhaven + Stony Brook). 1894 mAh/g reversible capacity at 300 cycles (2 A/g), 0.027%/cycle decay, 85% ICE, 3.3x improvement over pristine Si MP, 45% less tensile-stress variation than SWCNT-only coatings. ACS Applied Energy Materials 7(17), 7220-7231 (2024). --- ## Graphene and MXene Supercapacitor Electrodes Source URL: https://www.cheaptubes.com/graphene-mxene-supercapacitor-electrodes/ By Mike Foley , Founder, Cheap Tubes Inc. & CTI Materials LLC. Part of the Graphene & CNT Battery Applications hub. TL;DR Graphene nanoplatelets, reduced graphene oxide, and MXene (Ti 3 C 2 T x ) serve as high-surface-area electrodes in electrochemical double-layer capacitors (EDLCs) and pseudocapacitors. Graphene provides up to 2,630 m²/g theoretical surface area; practical electrodes achieve 200–700 m²/g. MXene contributes both double-layer capacitance and surface-redox pseudocapacitance, achieving volumetric capacitances above 1,500 F/cm³ in optimized films — among the highest reported for any electrode material. This page covers EDLC vs pseudocapacitor selection, material-grade choice, and procurement considerations for graphene and MXene supercapacitor electrodes. EDLC vs pseudocapacitor vs hybrid Supercapacitors store charge by three distinct mechanisms, and the right carbon material depends on which mechanism dominates: Electrochemical double-layer capacitors (EDLCs). Charge is stored physically at the electrode-electrolyte interface — no chemical reaction, just ion adsorption on a high-surface-area substrate. Energy density is modest (5–10 Wh/kg) but power density is very high (5,000–10,000 W/kg) and cycle life is essentially unlimited (10 6 + cycles). EDLCs use porous carbon, activated carbon, graphene, or rGO as the electrode material. Pseudocapacitors. Charge is stored via fast, reversible surface redox reactions in addition to double-layer adsorption. Energy density is higher than EDLCs (10–30 Wh/kg) at moderate cost in cycle life (10 4 –10 5 cycles). Common pseudocapacitive materials: MnO 2 , RuO 2 , conductive polymers, and (notably) MXene Ti 3 C 2 T x . Hybrid supercapacitors. Combine an EDLC electrode (carbon, high power) with a battery-like electrode (lithium intercalation material, high energy). Energy density approaches 50 Wh/kg with power density retained at 1,000–5,000 W/kg. Hybrid devices increasingly dominate commercial supercapacitor product launches in 2024–2026. The trade-offs determine material choice. For pure EDLC: maximize surface area and conductivity. For pseudocapacitor: choose a material with reversible surface redox at the operating voltage. For hybrid: carbon electrode is typically graphene-based; battery electrode follows lithium-ion design. Three supercapacitor mechanisms - EDLC, pseudocapacitor, and hybrid - each suits a different carbon material grade. Why surface area and conductivity = supercap performance Specific capacitance (F/g) at the EDLC electrode is proportional to electrochemically accessible surface area times the dielectric capacitance of the electrolyte double layer. Practical EDLC carbons deliver 100–250 F/g in aqueous electrolyte and 80–200 F/g in organic electrolyte. Graphene and rGO can exceed 300 F/g in optimized configurations. Two surface-area caveats matter: Pore size matters more than total surface area. Pores smaller than the solvated ion (1–2 nm for organic electrolytes, 0.5–1 nm for aqueous) contribute little to capacitance because ions cannot access them. Optimal carbon electrodes have a hierarchical pore structure: meso-pores for ion transport plus narrow micro-pores tuned to the solvated ion size for high-density adsorption. Conductivity sets the rate ceiling. A high-surface-area carbon with poor conductivity delivers excellent low-rate capacitance but cannot maintain it at high rates. Graphene and MXene have intrinsic in-plane conductivities orders of magnitude higher than activated carbon, which is the reason they dominate high-power supercapacitor research. For graphene specifically, the practical challenge is that graphene sheets restack into multilayer assemblies during electrode fabrication — losing most of the theoretical surface area. Successful graphene supercapacitor electrodes use spacers (curved sheets, nanotube intercalation, polymer linkers) to prevent restacking and maintain accessible surface area. Pristine graphene restacks during drying losing surface area - CNT spacers, polymer linkers, or 3D structures preserve accessibility. Material-by-material breakdown Graphene nanoplatelets (GNP) and few-layer graphene. Conductive backbone for EDLC electrodes. Practical specific capacitances 120–200 F/g in aqueous electrolyte at moderate rates. Lower capacitance than activated carbon at low rates, but far higher rate capability and far better cycle stability. Common pairing: GNP + activated carbon hybrid composite, which combines GNP's conductivity with activated carbon's surface area. Available from Cheap Tubes' GNP catalog . Graphene oxide (GO). Used primarily as a precursor for reduced graphene oxide electrodes. GO itself is electrically insulating because of the oxygen functional groups; it must be reduced to rGO before use as a supercap electrode. GO's solubility in water and aqueous binders makes it the easiest graphene-family material to process at scale. Available via Cheap Tubes' GO catalog . Reduced graphene oxide (rGO). Conductivity restored, defect density tunable via reduction conditions. Practical capacitances 150–250 F/g. rGO defects are sometimes beneficial — they introduce pseudocapacitive contributions from residual oxygen groups, raising total capacitance. rGO is the most common graphene-family electrode in published supercapacitor work. MXene Ti 3 C 2 T x . The standout 2D material for pseudocapacitors. Layered structure with intercalated water and surface-terminating groups (-O, -OH, -F denoted T x ) that participate in reversible surface redox. Volumetric capacitances exceed 1,500 F/cm³ in dense films — among the highest reported for any electrode material. Areal capacitances of 1–2 F/cm² in thick coatings. Limitations: oxidative degradation in ambient air over long storage; performance dependent on synthesis-induced surface chemistry. Available via Cheap Tubes' MXene category . Composite electrodes. Most published high-performance supercap electrodes combine two or more carbon morphologies — for example, GNP backbones interleaved with activated carbon spacers, or MXene + CNT pillared structures that prevent MXene restacking. Hybrid electrodes are the current state-of-the-art for commercial-grade performance. MXene Ti3C2Tx delivers two simultaneous charge storage mechanisms: double-layer capacitance plus surface redox pseudocapacitance. Pseudocapacitive contributions of MXene MXene's high volumetric capacitance comes from two simultaneous mechanisms: Double-layer capacitance from the high accessible surface area between layered Ti 3 C 2 T x sheets — comparable to a high-quality EDLC carbon. Surface-redox pseudocapacitance from oxidation-state changes of surface Ti atoms in the presence of protons or other cations. The functional groups (-O, -OH, -F) on the MXene surface modulate the redox potential and the available redox capacity. This is the contribution that distinguishes MXene from a pure-EDLC graphene electrode. The combined effect is volumetric capacitance several times that of activated carbon or pristine graphene, with rate capability that scales with the in-plane MXene conductivity. The technology trade-offs: MXene cost is higher than graphene-family materials, and ambient-air stability is more limited (storage and processing require inert or controlled atmospheres for the highest-quality grades). For supercapacitor R&D and commercial development teams evaluating MXene, the practical specifications to check are: Ti 3 C 2 T x layer count (mono vs few-layer), surface termination distribution (-O, -OH, -F ratio), and pre-intercalation state (delaminated vs multilayer). Pore size matching determines real capacitance - pores must accept the solvated ion without excluding it. Material specs for supercap electrodes Material Practical capacitance (F/g) Best application Notes GNP (5–25 µm lateral, 5–15 nm) 100–180 EDLC conductive backbone Restacking is the main loss mechanism rGO (0.5–5 µm lateral) 150–250 EDLC + mild pseudocap Defect-stabilized, easy to process GO (precursor only) Reduce to rGO in situ Water-soluble, easy slurry processing MXene Ti 3 C 2 T x 300–500 (mass), 1,500 F/cm³ (vol) Pseudocapacitor, hybrid Highest volumetric capacitance; air-stability caveat Activated carbon + GNP composite 200–280 Commercial EDLC Best cost-performance for production Loading in the final electrode is typically 70–95 wt% active carbon material, 5–15 wt% binder (PTFE or PVDF), 0–10 wt% conductive additive (carbon black or CNT). For composite electrodes, mass ratios of the carbon components are typically optimized empirically. MXene Ti3C2Tx delivers 300-500 F/g gravimetric and 1500+ F/cm³ volumetric capacitance - 2-5x better than graphene-only electrodes. For pilot or production-scale electrode coating, dispersion uniformity again drives yield. Surfactant-stabilized Flexiphene formulations are well-suited to graphene and rGO supercapacitor electrode coatings where standard NMP-based dispersion would otherwise re-bundle. Polyaniline and polymer-composite electrodes. A growing fraction of pseudocapacitor electrode formulations combine MXene or graphene with conductive polymers — particularly polyaniline (PANI) — that contribute both pseudocapacitance and mechanical robustness. CTI Materials holds patent coverage ( U.S. Patents 10,049,783 and 11,961,630 ) on CNT + graphene/GO/GNP composites with polyaniline, polyaminotriazole, polyimide, polyamide, nylon, and polyester polymer matrices. For supercapacitor R&D and production buyers integrating conductive-polymer composites, the Flexiphene patented dispersion technology provides validated formulations covering these exact polymer-nanocarbon chemistries. Cheaptubes products for supercapacitor applications Graphene Nanoplatelets — multiple lateral sizes and thicknesses for EDLC and hybrid electrodes Graphene Oxide — for in-situ rGO electrode preparation MXene — Ti 3 C 2 T x powder and films for pseudocapacitor R&D Multi-Walled Carbon Nanotubes — for pillared MXene-CNT structures preventing restacking Flexiphene surfactant-stabilized dispersions — for production-scale electrode coating For custom MXene or graphene specifications, contact Cheap Tubes Inc. directly . Authoritative external references Stoller, M. D. et al. — graphene-based ultracapacitors (2008) ( Nano Letters ) Lukatskaya, M. R. et al. — MXene for high-power supercapacitors (2013) ( Science ) Ghidiu, M. et al. — clay-like MXene with high volumetric capacitance (2014) ( Nature ) Raccichini, R. et al. — graphene/GO/rGO in batteries and electrochemical capacitors, critical review (2015) ( Nature Materials ) Bonaccorso, F. et al. — graphene for batteries, supercapacitors and beyond (2016) ( Nature Reviews Materials ) Anasori, B. et al. — review of 2D MXenes for energy storage (2017) ( Nature Reviews Materials ) Simon, P. & Gogotsi, Y. — perspectives on supercapacitors (2020) ( Nature Materials ) Comprehensive review — electrochemical energy storage applications of graphene oxide including supercapacitors (2024) ( Energy & Fuels ) (External links reflect representative peer-reviewed literature; no endorsement implied.) Frequently asked questions Graphene or MXene — which is better for supercapacitors? It depends on the metric. For gravimetric capacitance and cost, graphene-family materials (GNP, rGO) lead. For volumetric capacitance and pseudocapacitive contribution, MXene Ti 3 C 2 T x is best-in-class. For commercial production, graphene-based EDLCs dominate by cost; MXene leads in volumetric energy density for R&D and emerging applications. Why doesn't pristine graphene match its theoretical capacitance? Restacking. Graphene sheets attract each other strongly during electrode drying — multi-layer assemblies form that lose most of the theoretical surface area. Successful electrodes use spacers (CNT intercalation, polymer linkers, hierarchical structures) to keep sheets separated and surface area accessible. Can MXene be used in aqueous and organic electrolytes? Yes to both, with different performance characteristics. Aqueous electrolytes deliver the highest pseudocapacitive contribution (proton-mediated surface redox). Organic electrolytes enable higher operating voltage windows but reduce pseudocapacitance. Ionic-liquid electrolytes are increasingly used for high-voltage MXene cells. How stable is MXene in ambient air? Pristine Ti 3 C 2 T x MXene degrades over weeks-to-months in ambient air, particularly in humid conditions. Storage under inert atmosphere or in solvent dispersions slows degradation. Surface-functionalized MXene variants and protective coatings are active development areas for improving shelf life. What's the role of carbon black in supercap electrodes? In most commercial supercapacitor electrodes, the active carbon (activated carbon, graphene, rGO) provides most of the capacitance, and 5–15 wt% carbon black is added for electrical connectivity to the current collector. Replacing carbon black with CNT or graphene in the conductive-additive role can reduce loading while improving rate capability — same percolation argument as in lithium-ion cathodes. Continue reading Hub: Graphene & CNT Battery Applications Previous spoke: Silicon-CNT and Graphene Anodes Next spoke: CNT & Graphene in Li-S, Li-air, and Solid-State Batteries About the author Mike Foley is the founder of Cheap Tubes Inc. and CTI Materials LLC. He holds 2 granted U.S. patents (10,049,783 and 11,961,630) in carbon nanomaterial applications, with additional patents in prosecution. His patented materials were selected by NASA for the Enceladus mission as a dual-capacitance layer in ion-selective electrodes. Mike has supplied carbon nanomaterials to battery R&D and production for 21 years. --- ## CNT and Graphene in Lithium-Sulfur, Lithium-Air, and Solid-State Batteries Source URL: https://www.cheaptubes.com/cnt-graphene-next-gen-batteries-li-s-li-air/ By Mike Foley , Founder, Cheap Tubes Inc. & CTI Materials LLC. Part of the Graphene & CNT Battery Applications hub. TL;DR Lithium-sulfur (Li-S), lithium-air (Li-O 2 ), and solid-state battery chemistries promise 2–10× the energy density of conventional lithium-ion, but each faces a distinct materials challenge that carbon nanotubes and graphene help solve. In Li-S, porous CNT and graphene hosts trap soluble polysulfide intermediates that would otherwise shuttle between electrodes and destroy capacity. In Li-air, CNT/graphene scaffolds catalyze oxygen reduction and accommodate Li 2 O 2 deposition. In solid-state cells, graphene at the electrolyte/electrode interface improves wettability and reduces interfacial resistance. This page covers R&D-grade carbon material selection and procurement for these next-generation chemistries. The polysulfide shuttle problem in Li-S Lithium-sulfur cells have a theoretical specific energy of approximately 2,600 Wh/kg — roughly 5× that of conventional lithium-ion. The cathode is elemental sulfur, which is abundant, cheap, and lightweight. The barrier to commercialization is the polysulfide shuttle effect: During discharge, sulfur progressively combines with lithium through intermediate lithium polysulfides (Li 2 S 8 , Li 2 S 6 , Li 2 S 4 , Li 2 S 2 ) before reaching the final Li 2 S product. The mid-chain polysulfides (Li 2 S 8 , Li 2 S 6 , Li 2 S 4 ) are soluble in the conventional liquid electrolyte. Once dissolved, they diffuse across the separator to the lithium anode, react with lithium metal directly, and either form an insulating layer on the anode or return to the cathode as longer-chain polysulfides — a parasitic shuttle that consumes active material and lithium with every cycle. The result: pristine sulfur cathodes lose more than 50% of capacity within the first 50 cycles. The shuttle effect, not the sulfur itself, is the bottleneck. Carbon nanostructures address this by trapping polysulfides physically and chemically before they can dissolve and diffuse. Polysulfide shuttle is the Li-S failure mode - CNT scaffolds + GO trapping layers solve it for 10x cycle life improvement. Carbon hosts for sulfur cathodes Three carbon-host architectures dominate published Li-S cathode work: 1. Mesoporous CNT scaffolds. Sulfur is melt-infiltrated into the pores of a CNT network. The high-aspect-ratio CNT framework provides electrical connectivity to the sulfur and physically confines the polysulfide intermediates within the pore network. Best-performing implementations use SWCNT 99% or MWCNT 99.9% with engineered pore sizes 2–10 nm. 2. Graphene oxide trapping layers. GO has oxygen functional groups (-OH, -COOH, epoxy) that interact chemically with polysulfide species. Polysulfides bond to the oxygen groups, preventing dissolution. GO is used both as the sulfur host and as a separator interlayer that catches escaping polysulfides. Loadings 20–60 wt% GO in the cathode are common in R&D formulations. 3. Hierarchical CNT/graphene composite hosts. Combining CNT scaffolding (electrical highway, mechanical support) with graphene oxide trapping (chemical polysulfide binding) yields composite cathodes with both mechanisms operating simultaneously. Most published high-cycle-life Li-S cells in 2024–2026 use this hybrid approach. Material specifications for Li-S cathode hosts: Material Function Loading Notes SWCNT 99% Conductive scaffold for sulfur 5–15 wt% High aspect ratio, low ash MWCNT 99.9% Mesoporous host 10–30 wt% Best for pore-engineering studies Graphene oxide Chemical polysulfide trap 20–50 wt% Oxygen functional groups bind LiS x Reduced GO Conductive backbone + trap 20–40 wt% Partial defect retention preserves binding The high carbon loading (often 30–50 wt% in academic R&D) is the trade-off for cycle life — sulfur utilization drops as carbon mass goes up. Production-feasibility work targets 20% carbon while maintaining shuttle suppression. Lithium-air cathodes Lithium-air (Li-O 2 ) cells have a theoretical specific energy near 11,400 Wh/kg using oxygen from ambient air as the cathode reactant — the highest of any practical battery chemistry. The cathode reaction forms lithium peroxide (Li 2 O 2 ), an insulating solid that must accumulate on a porous conductive scaffold during discharge and be decomposed back to lithium and oxygen during charge. Carbon scaffolds are the dominant cathode architecture in Li-air R&D for three reasons: Porosity for Li 2 O 2 accommodation. Discharge product Li 2 O 2 is an insulating solid that must accumulate without blocking oxygen access. Porous CNT or graphene networks provide the void space for deposition while maintaining oxygen diffusion paths. Catalytic activity for oxygen reduction. Defective graphene and N-doped CNT exhibit measurable electrocatalytic activity for the oxygen reduction reaction (ORR), reducing the cathode overpotential during discharge. Conductive backbone for insulating discharge products. Once Li 2 O 2 accumulates, only the carbon scaffold can carry current; the discharge product itself is insulating. CNT/graphene scaffolds maintain electrical connectivity to the deposition sites. Material specifications converge on similar grades to Li-S work: high-purity SWCNT or MWCNT (99%+), and high-quality graphene oxide or rGO. The lower commercial volume of Li-air R&D vs Li-S means specifications are typically academic-grade rather than industrial production. Carbon scaffolds enable Li-air cells by accommodating Li2O2 deposition while maintaining O2 diffusion paths and electrical connectivity. Solid-state battery interfaces Solid-state batteries replace the liquid electrolyte with a solid-electrolyte layer (sulfide-based, oxide-based, or polymer-based). The fundamental advantage is safety and high-voltage compatibility; the fundamental challenge is the electrode-electrolyte interface, where poor contact creates high interfacial resistance and cycle-life problems. Graphene-family materials appear in solid-state battery research in two roles: Interfacial conductive layer. A thin graphene or rGO film at the electrode/solid-electrolyte interface improves electrical and ionic contact, reducing the impedance ladder that limits high-rate cycling. Layer thicknesses of 50 nm to 1 µm are typical. Cathode composite for sulfide solid electrolytes. Sulfide solid electrolytes are sensitive to oxidation at high-voltage cathodes. CNT and graphene composites with the cathode active material can buffer the interface and extend the stable voltage window. Solid-state work is currently the smallest commercial volume of the four next-gen chemistries but the largest R&D pipeline, with multiple commercial deployment targets in 2027–2030. Graphene interlayers at electrode/solid-electrolyte boundaries reduce impedance and extend solid-state battery cycle life. Polymer electrolytes and CNT/graphene interfaces Solid-state batteries using polymer-electrolyte architectures rely on a different set of polymer chemistries than conventional lithium-ion: polyethylene oxide (PEO) and its successors, polyimide for high-temperature operation, and polyaminotriazole-family coordination polymers for high-conductivity solid electrolytes under R&D. The polymer-electrolyte/electrode interface is one of the dominant performance bottlenecks for solid-state cells, and CNT/graphene composite interlayers are an active area of research for improving this interface. CTI Materials' Flexiphene patent portfolio ( U.S. Patents 10,049,783 and 11,961,630 ) covers CNT + graphene/GO/GNP composites with the exact polymer matrices appearing in solid-state battery R&D — polyimide, polyamide, polyaniline, polyaminotriazole, nylon, and polyester. For research groups and battery-startup R&D teams working on polymer-electrolyte solid-state cells, this means a single technology source covers both the carbon nanomaterial and the patent-protected polymer-composite formulation chemistry. The Flexiphene patented system provides NASA-validated dispersion performance in these exact polymer systems. Material specs for R&D-grade work Next-gen battery R&D requires the highest-purity carbon grades for two reasons. First, metal residuals (catalyst remnants from CVD synthesis) interfere with electrochemical measurement — they catalyze unwanted side reactions, mask intrinsic capacity, and complicate interpretation of published results. Second, the small batch sizes typical of academic R&D allow premium-grade procurement without prohibitive cost. Recommended grades: SWCNT 99% — primary scaffold material; lowest ash content available in catalog grades; available in 0.5–10 g batches at Cheap Tubes MWCNT 99.9% — high-purity multi-walled CNT for pore engineering and percolation studies Graphene Oxide — high oxygen functional density for polysulfide trapping Single-Layer Graphene Oxide — monolayer GO for trapping-layer R&D Fullerenes (C 60 , C 70 ) — molecular carbon for electrocatalysis and interface studies For specific batch characterization (TGA ash content, BET surface area, Raman, TEM imaging), Cheap Tubes provides per-batch characterization data on request — important for reproducible academic publication. R&D-grade carbon material selection across Li-S, Li-air, and solid-state chemistries - 99 percent purity required for academic publication. Cheaptubes products for next-gen battery R&D Single-Walled Carbon Nanotubes — 95–99.9% purity grades suitable for Li-S, Li-air, and solid-state R&D Multi-Walled Carbon Nanotubes — 98–99.9% purity options for pore-engineering studies Graphene Oxide — including single-layer GO for polysulfide trapping research Fullerenes (C 60 , C 70 ) — 95–99.9% purity grades for electrocatalysis and molecular electronics work MXene — emerging role in solid-state battery interfaces For academic R&D requiring documented characterization on each batch, contact Cheap Tubes Inc. directly . Free samples are available for qualifying R&D projects. Battery deployment roadmap 2026-2030: Si-C anodes shipping now, sulfide solid-state by 2028, Li-S by 2029, polymer/oxide solid-state and Li-air at 2030+. Authoritative external references Ji, L., Rao, M., Zheng, H. et al. — graphene oxide as sulfur immobilizer in high-performance Li/S cells, foundational paper for GO trapping (2011) ( JACS ) Ji, X. et al. — sulfur-graphene oxide nanosheet cathode for Li-S (2011) ( Nature Communications ) Manthiram, A. et al. — review of Li-S battery cathode design (2014) ( Chemical Reviews ) Janek, J. & Zeier, W. G. — solid-state battery roadmap (2016) ( Nature Energy ) Liu, T. et al. — review of Li-air battery electrocatalysts (2017) ( Chemical Society Reviews ) Li, X. et al. — self-catalyzed Co 4 N + N-doped CNTs as bifunctional cathode for flexible Li-air batteries (2024) ( ACS Nano ) Graphene and CNT-based hybrid nanocomposite review covering Li-S, Li-air, supercapacitors, fuel cells (2025) ( Synthetic Metals ) DOE Office of Electricity — Energy Storage Grand Challenge Roadmap (External links reflect representative peer-reviewed literature; no endorsement implied.) Frequently asked questions Why does Li-S need a carbon host — why not just use sulfur directly? Pure sulfur cathodes lose more than 50% of capacity within 50 cycles because polysulfide intermediates dissolve in the electrolyte and shuttle to the anode. The carbon host traps polysulfides physically (in pores) and chemically (oxygen groups bind LiS x ), keeping the sulfur active material in the cathode and extending cycle life by 10× or more. Is GO or rGO better for polysulfide trapping? GO has more oxygen functional groups and stronger chemical binding to polysulfides — better trapping per gram. rGO has higher electrical conductivity — better current collection. Most high-performance Li-S cathodes use a combination: GO for the trapping interlayer or external layer; rGO or CNT for the conductive scaffold. What CNT purity is needed for Li-air R&D? 99%+ at minimum. Metal residuals from synthesis catalysts interfere with oxygen reduction kinetics — they can either catalyze unwanted side reactions or dominate the measured cathode performance. For peer-reviewed publication, 99.5–99.9% MWCNT or 99% SWCNT is standard. When will solid-state batteries reach commercial deployment? Most credible roadmaps target initial commercial deployment in 2027–2029, with broader market entry through 2030. Sulfide solid-electrolyte cells lead the production timeline; oxide and polymer solid-electrolyte systems target later windows. Carbon-graphene interface engineering is a critical enabler for high-rate solid-state cells. Are fullerenes used in any commercial battery? Not currently in commercial production. Fullerene research in batteries focuses on electrocatalysis (oxygen reduction in Li-air), interface engineering (solid-state cathodes), and as a molecular probe for studying lithium-carbon interactions. Commercial deployment requires step-changes in either fullerene synthesis cost or in a battery chemistry where fullerenes are uniquely enabling — neither has yet emerged. Continue reading Hub: Graphene & CNT Battery Applications — overview of all four application categories Previous spokes: CNT Cathode Conductive Additive Silicon-CNT and Graphene Anodes Graphene & MXene Supercapacitor Electrodes Buying guides: SWCNT , MWCNT , GNP About the author Mike Foley is the founder of Cheap Tubes Inc. and CTI Materials LLC. He holds 2 granted U.S. patents (10,049,783 and 11,961,630) in carbon nanomaterial applications, with additional patents in prosecution. His patented materials were selected by NASA for the Enceladus mission as a dual-capacitance layer in ion-selective electrodes. Mike has supplied carbon nanomaterials to battery R&D and production for 21 years. Application Spotlight: 648 mAh/g Li-S Battery Cathode with Cheap Tubes GO-Derived rGO/ZnS — Politecnico di Torino group uses Cheap Tubes graphene oxide as precursor for sulfur and nitrogen co-doped rGO embedded with ZnS nanoparticles. The catalytic cathode delivers 648 mAh/g at 1C (vs 517 baseline), 48.2% capacity retention at 750 cycles, and near-99% Coulombic efficiency. Colombo et al., Nanomaterials 13(15), 2149 (2023). --- # Additional Content — Research Watch & Supplier Comparisons > This appendix was added 2026-08-10. It indexes new Research Watch entries (papers and conference abstracts we're tracking, regardless of whose material was used) and supplier comparison pages published since the June 19, 2026 build. See [/llms.txt](https://www.cheaptubes.com/llms.txt) for the concise URL index. --- ## GO + Perovskite QD Memristor Doubles SNR for Low-Light Neuromorphic Vision Source URL: https://www.cheaptubes.com/research-watch-go-memristor-neuromorphic-vision/ Research Watch · By Mike Foley , Founder, Cheap Tubes Inc. · Published: July 22, 2026 Research Watch tracks papers researchers are chasing right now on carbon nanotube and graphene applications — regardless of whose material was used. This entry covers a 2026 Applied Physics Letters paper from Hebei GEO University and Shijiazhuang Tiedao University (China) on a flexible graphene oxide (GO) + perovskite quantum dot memristor for low-light neuromorphic vision. Cheap Tubes did not supply material for this study. We’re covering it because the device chemistry maps cleanly onto our graphene oxide catalog, for researchers who want to understand, replicate, or extend the approach. The Problem: Vision Sensors That Fail in Low Light Flexible neuromorphic vision systems — artificial retinas that sense and compute in the same device, rather than shuttling raw pixel data to a separate processor — depend on memristors: components that rapidly tune their own resistance in response to an optical input, the way a biological synapse adjusts signal weight. That works well in good lighting. In dim conditions, low-contrast images carry more noise than signal, and most memristor materials don’t have enough dynamic range in their conductance to separate a faint object from background noise before the data ever reaches downstream circuitry. For wearable and curved-surface vision applications — skin-mounted sensors, flexible cameras, low-power edge vision — that noise floor is the limiting factor, and it has to be solved at the material level, not just in software. What the Team Did A team led by Jingjuan Wang and Lingzhi Tang at Hebei GEO University’s College of Information Engineering, working with Shijiazhuang Tiedao University, built a flexible optoelectronic memristor using a switching layer that combines graphene oxide (GO) sheets with perovskite quantum dots . The composite behaves differently in the dark than under illumination: under dim light, the memristor’s conductance range expands, which lets the device filter noise more effectively and, in effect, amplify faint optical signals before they’re processed further. Fed low-contrast images, the device outputs clean silhouettes and extracts usable features for object recognition — all handled locally on the flexible sensor itself, with no additional circuitry required. The GO component is central to both the electrical behavior (it’s part of the switching-layer chemistry) and the mechanical durability: the composite kept operating reliably after thousands of bending cycles, and its resistance to cracking under deformation is what makes it a realistic candidate for wearable use, including attachment to curved skin to pick up weak ambient light signals. Key Results GO + Perovskite QD Flexible Memristor 2× signal-to-noise ratio for noisy, low-light images >10% recognition accuracy gain on noisy, low-light images 1000s bending cycles survived no cracking, wearable-durable 0 extra circuits required filtering handled on-sensor Source: Yue, Zhao, Li, Tang, Ren & Wang — Applied Physics Letters 129, 033506 (2026). Hebei GEO University + Shijiazhuang Tiedao University. DOI: 10.1063/5.0339447. Why signal-to-noise and accuracy move together The reported gains — signal-to-noise ratio doubling and recognition accuracy improving more than 10% — both trace back to the same mechanism: under dim illumination the memristor’s usable conductance range widens, so small differences in incoming light produce clearly distinguishable resistance states instead of getting lost in device noise. Foreground and background separate cleanly as a direct result, which is what makes downstream object recognition more accurate without any additional image processing. Why flexibility and durability matter here A memristor that only works rigid and flat isn’t useful for the applications this work targets — curved-surface and wearable vision sensing. The GO-based composite continued operating reliably after thousands of bending cycles and resisted cracking under deformation, which the team highlights as the property that makes attaching the sensor to curved skin (to pick up weak ambient light signals) a realistic near-term application rather than a lab-only demonstration. Replicating or Extending This Work The team’s public description of the material cites graphene oxide (GO) sheets combined with perovskite quantum dots as the switching-layer composite. The published coverage of this work does not specify a layer count, lateral flake size, or oxidation degree for the GO component — so we can’t point to an exact spec match. What we can do is name the comparable Cheap Tubes material: our Single Layer Graphene Oxide is the longest-standing, most general-purpose GO grade in our catalog and the natural starting point for researchers exploring this class of switching-layer chemistry. Product clarification: because the paper doesn’t specify GO grade details, this is a spec match on the generic term “graphene oxide,” not a citation of Cheap Tubes material used in the study. If your own device work needs a different GO grade — smaller flake size for thin-film uniformity, larger lateral size for fewer grain boundaries, or a reduced GO (rGO) precursor — see the full Graphene Oxide Buying Guide for the layer-count and flake-size decision tree across our GO product line. Graphene Oxide for Memristor and Neuromorphic Switching-Layer R&D Single-layer graphene oxide for resistive-switching composites, optoelectronic memristor research, and flexible device R&D. The general-purpose, longest-standing GO grade in the Cheap Tubes catalog — a spec-matched starting point for this class of switching-layer chemistry, not a citation of material used in the study above. See Single Layer Graphene Oxide → Browse all Graphene Oxide grades Frequently Asked Questions What did the Hebei GEO University team demonstrate? A flexible optoelectronic memristor built from a graphene oxide and perovskite quantum dot composite switching layer, designed for low-light neuromorphic vision. Under dim illumination the device’s conductance range widens, which filters noise and amplifies faint optical signals locally on the sensor. For noisy, low-light images the team reports recognition accuracy improving more than 10% and signal-to-noise ratio doubling, with reliable operation after thousands of bending cycles. Did Cheap Tubes supply the material used in this study? No. This is Research Watch coverage of an early-stage published paper, not an Application Spotlight. The Hebei GEO University and Shijiazhuang Tiedao University team did not use Cheap Tubes material. We cover papers like this because the material class maps to our catalog, so researchers can find a comparable starting point — we never imply our material was used unless it actually was. What material would I need to replicate this work? The published description cites graphene oxide sheets combined with perovskite quantum dots as the switching-layer composite, without specifying GO layer count, flake size, or oxidation degree. The comparable Cheap Tubes material is Single Layer Graphene Oxide, our longest-standing general-purpose GO grade. Perovskite quantum dot synthesis is outside the Cheap Tubes catalog and would need to be sourced or synthesized separately. Why does graphene oxide show up in a memristor’s switching layer? GO’s oxygen-containing functional groups and tunable defect density give it the kind of variable electrical resistance that resistive-switching (memristive) devices rely on. Combined with a photo-responsive material like perovskite quantum dots, the composite can shift its resistive-switching behavior based on light exposure, which is the mechanism this paper uses to build a light-sensitive artificial synapse. Citation Ziwei Yue, Siyu Zhao, Yuchun Li, Lingzhi Tang, Shuxia Ren, and Jingjuan Wang (2026). Flexible optoelectronic memristor with photo-enhanced resistive switching for low-light visual perception. Applied Physics Letters , 129(3), 033506. doi:10.1063/5.0339447 . Hebei GEO University, College of Information Engineering; Shijiazhuang Tiedao University. About the author Mike Foley founded Cheap Tubes Inc. in 2005 and holds two granted U.S. patents in nanoparticle dispersion . Cheap Tubes (Vermont, USA) supplies research-grade carbon nanotubes, graphene, graphene oxide, MXene, and specialty nanomaterials. See selected publications → About Mike Foley · Contact / Request a quote · All resources --- ## Polymer-Assisted CNT Dispersion for Lithium-Ion Battery Electrodes Source URL: https://www.cheaptubes.com/research-watch-polymer-dispersed-cnt-li-ion-electrodes/ Research Watch · By Mike Foley , Founder, Cheap Tubes Inc. · Published: July 22, 2026 Research Watch tracks papers and conference abstracts researchers are chasing right now on carbon nanotube and graphene applications — regardless of whose material was used. This entry covers a 2026 ECS Meeting Abstract from Hansol Chemical (a Korean battery-materials company) on a polymeric dispersant for carbon nanotube (CNT) conductive additives in lithium-ion battery (LIB) electrodes. This is a conference abstract, not a full peer-reviewed paper — the published text is a short teaser ahead of the full presentation and doesn’t include the detailed numeric results a journal article would. Cheap Tubes did not supply material for this work. We’re covering it because uniform CNT dispersion in electrode slurries is one of the questions researchers bring to us most often, and this is one way to solve it. The Problem: CNTs Are Hard to Disperse in Electrode Slurries Carbon nanotubes are attractive as conductive additives for lithium-ion battery electrodes because their one-dimensional structure forms efficient conductive networks that significantly enhance electronic transport within the electrode — particularly valuable for high-energy and high-power LIB systems. The catch is that CNTs have strong van der Waals interactions that promote tightly bundled aggregates, which makes uniform dispersion in electrode slurries difficult. Poor dispersion leads to non-uniform conductive pathways and increased electrode resistance — the opposite of what the CNT additive is there to deliver. Achieving stable CNT dispersion while staying compatible with the LIB electrochemical environment is a real manufacturing constraint, not just a lab curiosity. What the Team Did The Hansol Chemical team (Jinju Eom, Kwang In Kim, and Se Man Kwon) designed a polymeric dispersant engineered to disperse CNTs effectively while maintaining electrochemical stability within the operating voltage window of lithium-ion batteries. The polymer’s molecular structure was built to enhance interfacial interactions with CNT surfaces and provide steric stabilization — a physical barrier effect that suppresses the CNTs from re-aggregating once dispersed. They evaluated dispersion behavior through rheological measurements (how the slurry flows and resists deformation) and microstructural characterization. According to the abstract, the designed polymer improves CNT dispersion stability and promotes well-connected conductive networks within the electrode structure, while maintaining electrochemical stability under battery-relevant conditions. Electrodes built with the polymer-assisted CNT dispersion reportedly show reduced internal resistance and improved electronic transport compared with conventional CNT dispersion systems, which the team links to enhanced DC resistance behavior and improved cycling stability in LIBs. The abstract does not report specific numeric values for any of these comparisons — that level of detail is typical of the full presentation or a follow-up journal paper, not the meeting abstract itself. Key Results (as Reported in the Abstract) Polymer-Assisted CNT Dispersion, LIB Electrodes Improved dispersion stability vs conventional CNT dispersion systems no numeric value reported in abstract Reduced internal resistance improved electronic transport no numeric value reported in abstract Improved cycling stability enhanced DC resistance behavior no numeric value reported in abstract Source: Eom, Kim & Kwon — ECS Meeting Abstracts MA2026-01, 2798 (2026). Hansol Chemical. DOI: 10.1149/ma2026-0172798mtgabs. Why this is directional, not quantified, coverage ECS Meeting Abstracts (published by The Electrochemical Society ahead of conference presentations) are typically 200-400 words and exist to summarize what will be presented, not to report full data tables. This one follows that pattern — it names the mechanism (steric stabilization via a purpose-built polymer), the evaluation methods (rheology, microstructural characterization), and the direction of every result (dispersion stability up, internal resistance down, cycling stability up), but doesn’t publish the underlying numbers. We’re covering it at this stage because the mechanism and problem statement are useful on their own, and because early visibility into live research trends is the point of Research Watch. If a fuller paper follows, we’ll cover that with the actual data. The mechanism: steric stabilization against CNT re-aggregation The core idea — a polymer engineered to interact with the CNT surface and physically block the tubes from re-bundling — is a well-established dispersion strategy (steric stabilization), applied here with an added constraint: the polymer also has to stay electrochemically stable inside a working lithium-ion cell’s voltage window, which rules out a lot of off-the-shelf dispersants developed for other industries. That’s the specific engineering problem this abstract is targeting, and it’s the same problem any lab or manufacturer dispersing CNTs into an electrode slurry runs into. Replicating or Extending This Work Product clarification: the abstract refers to “carbon nanotubes (CNTs)” generically and does not state a diameter, purity, wall count (single- vs multi-walled), or loading level — so there is no exact spec to match. Conductive-additive CNT work in lithium-ion electrodes overwhelmingly uses multi-walled carbon nanotubes for cost and conductive-network efficiency at practical loadings, so the closest general-purpose match in our catalog is Standard MWCNT (98% purity) , our longest-standing, broadest MWCNT line. For bulk conductive-additive work where cost per kilogram matters more than research-grade purity, the Industrial Grade MWCNT (90% purity) line is the lower-cost alternative. The Hansol Chemical approach adds dispersion assistance as a separate polymeric additive mixed into the slurry, rather than modifying the CNT surface itself. If your own formulation work would rather build dispersion assistance into the tube surface — covalent COOH or OH functional groups that improve wetting and reduce re-aggregation without a separate dispersant — the closest analog in our catalog is the Functionalized Carbon Nanotubes category (COOH-, OH-, and NH 2 -functionalized MWCNT across our Standard, Industrial, and Graphitized lines). These are two different dispersion strategies solving the same underlying problem — a separate polymer dispersant vs. surface chemistry built into the tube — and both are viable starting points depending on your process constraints. MWCNT Conductive Additives for Li-ion Electrode Dispersion R&D Multi-walled carbon nanotubes for lithium-ion, sodium-ion, and next-generation battery electrode conductive networks. Standard MWCNT (98% purity) for research-grade dispersion work, Industrial Grade MWCNT (90% purity) for cost-sensitive bulk formulation, and COOH / OH functionalized MWCNT where surface-chemistry-assisted dispersion is preferred over a separate polymeric dispersant. Browse Standard MWCNT → Browse Functionalized CNT Polymer-assisted dispersion is one route among several — polymer-free aqueous dispersion approaches, such as our own Flexiphene emulsions , take a different path to the same stability problem. Frequently Asked Questions What did the Hansol Chemical team report? An ECS Meeting Abstract describing a polymeric dispersant engineered to disperse carbon nanotubes in lithium-ion battery electrode slurries while remaining electrochemically stable within the battery’s operating voltage window. The polymer is designed to enhance interfacial interaction with the CNT surface and provide steric stabilization that suppresses re-aggregation. The abstract reports improved dispersion stability, reduced internal resistance, improved electronic transport, and improved cycling stability versus conventional CNT dispersion systems, without publishing specific numeric values. Is this a peer-reviewed paper or a conference abstract? It’s a conference abstract published by The Electrochemical Society (ECS Meeting Abstracts), not a full peer-reviewed journal article. Meeting abstracts are short summaries submitted ahead of a conference presentation and typically don’t include full data tables or numeric results. We’re covering it as early-stage research to watch, and we say so explicitly rather than treating it like a completed study. Did Cheap Tubes supply the material used in this study? No. This is Research Watch coverage of an early-stage conference abstract, not an Application Spotlight. The Hansol Chemical team did not use Cheap Tubes material, and the abstract doesn’t name any CNT supplier. We cover items like this because the underlying problem — CNT dispersion in electrode slurries — is directly relevant to researchers using our conductive-additive materials. What material would I need to replicate or extend this work? The abstract doesn’t specify CNT diameter, purity, or wall count, so there’s no exact SKU match. The general-purpose starting point for MWCNT conductive-additive work is our Standard MWCNT (98% purity); Industrial Grade MWCNT (90% purity) is the lower-cost bulk alternative. If you’d rather build dispersion assistance into the tube surface instead of formulating a separate polymeric dispersant, our COOH- and OH-functionalized MWCNT lines are the closest analog. The polymeric dispersant itself is not a Cheap Tubes product and would need to be sourced or developed separately. Citation Jinju Eom, Kwang In Kim, and Se Man Kwon (2026). Polymer-Assisted Dispersion of Carbon Nanotube for Improved Conductive Networks in Lithium-Ion Battery Electrodes. ECS Meeting Abstracts , MA2026-01(7), 2798. doi:10.1149/ma2026-0172798mtgabs . Hansol Chemical, South Korea. Conference abstract, The Electrochemical Society. About the author Mike Foley founded Cheap Tubes Inc. in 2005 and holds two granted U.S. patents in nanoparticle dispersion . Cheap Tubes (Vermont, USA) supplies research-grade carbon nanotubes, graphene, graphene oxide, MXene, and specialty nanomaterials. See selected publications → About Mike Foley · Contact / Request a quote · All resources --- ## Chemically Modified Porous Graphene for Cement Dispersion Stability Source URL: https://www.cheaptubes.com/research-watch-modified-porous-graphene-cement-dispersion/ Research Watch · By Mike Foley , Founder, Cheap Tubes Inc. · Published: August 10, 2026 Research Watch tracks papers and conference abstracts researchers are chasing right now on carbon nanotube and graphene applications, regardless of whose material was used. This entry covers a 2026 paper in the American Society of Civil Engineers’ Journal of Materials in Civil Engineering from a team at Guangxi University and Huazhong University of Science and Technology on chemically modifying three-dimensional porous graphene (3DG) so it stays dispersed in cement paste. The paper is peer-reviewed and ahead-of-print (accepted for the November 2026 print issue); the publisher’s full text, figures, and detailed data tables sit behind ASCE’s paywall. This coverage draws on the paper’s own published abstract, which reports real numeric results. We’ve quoted those, and we say plainly where the abstract’s detail ends and the paywalled full text begins. Cheap Tubes did not supply material for this study. We’re covering it because graphene dispersion stability in alkaline, cementitious environments is a live problem for anyone working with our graphene oxide or graphene nanoplatelet materials in construction or composite research. The Problem: Graphene Agglomerates in Cement’s Alkaline Pore Solution Graphene is one of the most-studied nanoscale reinforcements for cement-based materials. Its two-dimensional structure, high aspect ratio, and mechanical properties make it attractive for densifying microstructure, accelerating hydration, and improving strength and durability. The catch, well known in the cement-nanomaterials literature, is that graphene’s own van der Waals attraction pulls individual sheets back into stacked, agglomerated clumps almost as soon as they’re mixed into an aqueous system, and cement pore solution is an especially hostile environment for staying dispersed. Once cement starts hydrating, the pore solution rapidly becomes strongly alkaline (the literature typically cites pH in the 12.5–13.5 range, driven by dissolved calcium, sodium, and potassium hydroxides), and that high ionic strength compresses the electrostatic double layer that would otherwise keep charged graphene sheets apart. Agglomerated graphene doesn’t reinforce anything. It behaves like a coarse, poorly bonded inclusion, and the strength and durability gains the material is supposed to deliver don’t show up. High-quality graphene is also expensive relative to bulk cement, so agglomeration wastes a costly input on top of costing performance. Solving alkaline dispersion stability is the gatekeeping problem for graphene-cement research generally, not a detail specific to any one study. What the Team Did The Guangxi University-led team (Jingwei Ying, Hao Wang, Haijie Yan, Feiming Su, and Caishou Wei) started from three-dimensional porous graphene (3DG), a graphene architecture built as an interconnected porous network rather than flat, discrete platelets, and covalently modified it with polycarboxylate (PC), the same class of chemistry used in PC superplasticizers that concrete producers already use to control workability. The resulting material, which they call PC-modified 3DG (PG), was designed specifically to improve dispersion stability in cement’s alkaline environment rather than to change the graphene’s intrinsic mechanical properties. They tested PG at an extremely low dosage: 0.03% by mass of cement, which works out to only about 0.01% graphene content within the modified material, and evaluated dispersion behavior in solution and in cement paste directly, alongside rheology, hydration heat analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and mercury intrusion porosimetry (MIP) to see whether better dispersion actually changed the hardened microstructure. According to the paper’s own abstract, PG showed superior dispersibility and stability compared with unmodified 3DG, both in solution systems and within cement paste. The covalent polycarboxylate coating did what it was designed to do. Incorporating PG also slightly reduced the yield stress and plastic viscosity of the cement paste (a workability benefit alongside the strength benefit), and the hydration-heat, XRD, and SEM data indicated PG accelerated the hydration reaction and densified the resulting microstructure. MIP analysis showed the more homogeneous PG dispersion inhibited the formation of large pores and reduced total porosity, which the authors link to improved resistance to chloride ion diffusion, a durability property relevant to reinforced concrete service life. Key Results (as Reported in the Abstract) PC-Modified 3D Porous Graphene (PG), 0.03% Cement Mass Dosage +30.8% / +28.8% / +26.4% compressive strength vs. plain paste at 3 / 7 / 28 days −21.9% / −19.6% / −23.4% total porosity (MIP) vs. plain paste at 3 / 7 / 28 days 0.03% dosage by mass of cement ≈0.01% graphene content within PG Source: Ying, Wang, Yan, Su & Wei, Journal of Materials in Civil Engineering 38(11), ASCE (2026). DOI: 10.1061/JMCEE7.MTENG-23238. Figures as stated in the published abstract; full data tables, mix designs, and discussion are in the paywalled paper. Why alkaline dispersion stability is the whole ballgame Cement pore solution is not a mild aqueous environment. It is one of the more aggressive dispersion conditions a nanomaterial can be asked to survive. As cement hydrates, calcium hydroxide, sodium hydroxide, and potassium hydroxide dissolve into the mix water, driving pore-solution pH into the 12.5–13.5 range and pushing ionic strength well above what most dispersion strategies developed for neutral water or organic solvents were designed to handle. Two mechanisms usually keep nanosheets like graphene or graphene oxide apart in a liquid: electrostatic repulsion (charged surface groups pushing sheets away from each other) and steric hindrance (physical bulk, like an attached polymer chain, getting in the way of re-stacking). High ionic strength compresses the electrostatic double layer and screens surface charge, which is why electrostatic-only stabilization tends to fail in cement pore solution even when it works fine in plain water. That’s the specific reason a covalent, polymer-based modification, like the polycarboxylate coating in this paper, is a sensible design choice: steric stabilization from a bulky, covalently attached polymer chain is far less sensitive to ionic strength than charge-based stabilization alone. Getting this right at a very low dosage (0.03% by cement mass here) also matters economically. Graphene is expensive enough that dispersion strategies requiring high loadings to overcome agglomeration erode the cost case for using it at all. The mechanism: covalent polycarboxylate modification of a 3D porous network Two design choices stand out. First, starting from a three-dimensional porous graphene architecture rather than flat platelets: a porous, interconnected network changes how the material distributes through the paste and how it interacts with hydration products, compared with discrete 2D sheets. Second, using polycarboxylate specifically as the modifying chemistry: PC superplasticizers are already a known, cement-compatible chemistry (they’re the workhorse dispersant for cement particles themselves), so grafting PC onto the graphene surface borrows a chemistry the cement system already tolerates well, rather than introducing an unfamiliar surfactant or polymer that might interfere with hydration. The reported combination (better dispersion, slightly reduced yield stress and plastic viscosity, and a denser, less porous hardened microstructure) is a coherent picture: if the graphene stays dispersed instead of clumping, it can actually participate in and influence hydration and pore structure development, instead of sitting inert as an agglomerated inclusion. Replicating or Extending This Work Product clarification: the abstract describes the starting material as “three-dimensional porous graphene” without stating a manufacturer, lateral flake size, layer count, or oxidation state, so there is no exact SKU match, and we’re not going to pretend otherwise. 3D porous graphene architectures (foams, aerogels, self-assembled networks) are most commonly built starting from a graphene oxide dispersion. GO’s oxygen-containing functional groups make it water-dispersible and let it self-assemble (hydrothermally or via freeze-drying) into a 3D network before reduction. Cost matters here: cement additions are dosed by mass of cement, so even a low weight percent means bulk quantities of graphene material, and the price gap between a premium research-grade GO and an affordable, QC’d GO adds up fast at that scale. Our Graphene Oxide Powder (id 30170) is the practical starting point for cement and composite dispersion work: spray-dried, QC’d to a tight carbon-to-oxygen specification on every lot, and priced for the quantities this kind of research actually consumes. If your process calls for a partially-reduced sheet instead, our Reduced Graphene Oxide Industrial Grade (id 30171) is the equivalent cost-appropriate option on the reduced side. Both sit in our Graphene Oxide category . If instead your work calls for a ready-to-disperse graphene platelet material, adding bulk graphene content directly into a cement or composite mix without first building a self-assembled porous network, the more direct analog is our Graphene Nanoplatelets (GNP) line. Covalent polymer modification, as this paper used, is one route to alkaline-stable dispersion. Polymer-free aqueous dispersion approaches, such as our own Flexiphene emulsions , take a different path to the same stability problem. Which starting point makes sense depends on whether your process needs the graphene pre-dispersed and stable in water going in, or whether you’re building your own surface chemistry (like the PC grafting in this paper) as part of the research itself. Graphene Oxide & GNP for Cement & Composite Dispersion R&D Graphene Oxide Powder and Reduced Graphene Oxide Industrial Grade are priced and QC’d for pilot-scale cement and composite dispersion work, where additions are dosed by cement mass and material cost adds up fast. Graphene Nanoplatelets are the direct-dispersion option for bulk graphene content in cement, polymer, and composite formulations. Pre-dispersed aqueous Flexiphene emulsions are available where a polymer-free dispersion path is preferred. Browse Graphene Oxide → Browse Graphene Nanoplatelets Frequently Asked Questions What did the Guangxi University team report? A peer-reviewed paper in ASCE’s Journal of Materials in Civil Engineering describing polycarboxylate-modified three-dimensional porous graphene (PG) engineered to resist agglomeration in cement’s strongly alkaline pore solution. At 0.03% cement mass dosage, the paper’s abstract reports compressive strength gains of 30.8%, 28.8%, and 26.4% at 3, 7, and 28 days versus plain cement paste, alongside reduced total porosity and improved resistance to chloride ion diffusion, which the authors attribute to better dispersion enabling accelerated hydration and a denser microstructure. Is this a peer-reviewed paper or a preliminary abstract? It’s a peer-reviewed journal article, accepted and ahead-of-print in ASCE’s Journal of Materials in Civil Engineering (assigned to the November 2026 print issue, volume 38, issue 11). The publisher’s full text, figures, mix-design tables, and detailed discussion are behind ASCE’s paywall. This coverage is based on the paper’s own published abstract, which does report real numeric results. We’ve quoted those and linked the paywalled paper for anyone who wants the full dataset. Did Cheap Tubes supply the material used in this study? No. Cheap Tubes did not supply material for this study. This is Research Watch coverage of a paper we found relevant to graphene dispersion research, not an Application Spotlight, and the paper does not name Cheap Tubes or reference our products. We cover items like this because alkaline dispersion stability is directly relevant to researchers using our graphene oxide and graphene nanoplatelet materials in cement or composite work. What material would I need to replicate or extend this work? The abstract doesn’t specify a graphene manufacturer, flake size, or oxidation state for the starting 3D porous graphene, so there’s no exact SKU match. If you’re building a similar self-assembled porous network from a solution-processable precursor, Graphene Oxide Powder is the cost-appropriate starting point for cement-scale dosing, with Reduced Graphene Oxide Industrial Grade as the equivalent option on the reduced side. If you want a ready-to-disperse platelet material for direct addition to a cement or composite mix, Graphene Nanoplatelets are the more direct analog. The polycarboxylate surface modification itself is not a Cheap Tubes product and would need to be developed or sourced separately. Citation Jingwei Ying, Hao Wang, Haijie Yan, Feiming Su, and Caishou Wei (2026). Effects of Chemically Modified Three-Dimensional Porous Graphene for the Optimal Rheology and Mechanics of Cement Composite. Journal of Materials in Civil Engineering , 38(11). American Society of Civil Engineers (ASCE). doi:10.1061/JMCEE7.MTENG-23238 . Guangxi University, Huazhong University of Science and Technology, and Nanning University, China. Peer-reviewed journal article, ahead-of-print; full text paywalled by publisher. About the author Mike Foley founded Cheap Tubes Inc. in 2005 and holds two granted U.S. patents in nanoparticle dispersion . Cheap Tubes (Vermont, USA) supplies research-grade carbon nanotubes, graphene, graphene oxide, MXene, and specialty nanomaterials. See selected publications → About Mike Foley · Contact / Request a quote · All resources --- ## How Cheap Tubes Compares — Supplier Comparisons Hub Source URL: https://www.cheaptubes.com/compare/ Honest supplier comparisons How Cheap Tubes Compares A “lowest price” slogan tells you nothing about whether the material will work in your study. These are straight, fact-based comparisons of Cheap Tubes against other carbon-nanomaterials suppliers — so you can judge for yourself instead of taking a banner’s word for it. Compare us, supplier by supplier Cheap Tubes vs. ACS Material → Pricing, published specifications, a specification guarantee, and 21 years of results — side by side. Cheap Tubes vs. Nanografi Coming soon Cheap Tubes vs. Carbon Solutions Coming soon Cheap Tubes vs. Labxsci Coming soon Cheap Tubes vs. Matexcel Coming soon What every comparison weighs Price — real, published pricing at research and volume scale. Published specs & data — full specifications and representative characterization data, with a TDS and SDS on every order. Specification guarantee — the material meets its published spec, or it is replaced or refunded. Provenance & support — where it is made, who ships it, and who stands behind it. Track record — Cheap Tubes has supplied researchers worldwide since 2005. Compare us for yourself See full specifications, published data, and live pricing — or ask us anything. Browse Cheap Tubes → --- ## Cheap Tubes vs. ACS Material: Honest Supplier Comparison Source URL: https://www.cheaptubes.com/cheap-tubes-vs-acs-material/ An honest comparison Cheap Tubes vs. ACS Material If you searched for Cheap Tubes and saw a competitor’s ad on our name promising a “Lowest Price Guarantee,” we invite you to check that claim. Below is a straight, verifiable comparison of the two suppliers for carbon nanotubes, graphene and graphene oxide. Every figure can be confirmed on each company’s own website. The ad that prompted this page ACS Material is running paid Google ads against searches for our brand name — including the exact query “cheaptubes.com” — under a “Lowest Price Guarantee” headline. We think buyers deserve to see how the two suppliers actually compare, starting with the very claim that ad makes. A competitor’s paid ad served on a search for our company name. Source: Google Search, June 2026. Per Google’s public Ads Transparency Center, ACS Material is currently running roughly 25 U.S. ads. We could find no price-match terms or “lowest price” guarantee published anywhere on acsmaterial.com to support that headline. Who is Cheap Tubes? Cheap Tubes Inc. has supplied research-grade carbon nanomaterials from Vermont, USA since 2005 . For 21 years we have done one thing: make and supply high-quality carbon nanotubes, graphene and related nanomaterials to universities, national laboratories, and R&D teams worldwide. We are not a broad-line reseller adding nanomaterials to a catalog — carbon nanomaterials are our entire business, and our customers’ published results are our reputation. Cheap Tubes was founded by Mike Foley, president, who leads the company to this day. Side by side What matters to researchers Cheap Tubes ACS Material In business since 2005 — 21 years, carbon nanomaterials only 2011 Published specifications & characterization data Published — full specifications plus representative XPS, Raman, FTIR, TGA, AFM & C:O data; TDS + SDS with every order Specifications on product pages Specification guarantee Yes — meets the published spec or we replace it or refund you None stated Graphene oxide pricing* From $90/g From $135 MWCNT pricing at volume* Down to under $1/g From $120/g Specialty CNTs Deep range — functionalized, graphitized, helical & short CNTs Limited range Volume / tonnage capability Yes — research grams to production tonnage Primarily research quantities Based in United States (Vermont) United States (California) If you want the best carbon nanomaterials — fully specified, guaranteed to spec, openly priced, from a team that has done only this for 21 years — that’s us. And on the one thing their ad claims, price, the table above shows who actually wins. What we make that broad-line suppliers don’t Because carbon nanomaterials are all we do, our range goes deeper than a general catalog: Carbon nanotubes Single- and multi-walled, plus a full functionalized library (COOH, OH, NH₂, N-doped), graphitized MWCNTs, helical CNTs, and short CNTs for dispersion-sensitive work. Graphene & graphene oxide Graphene oxide and reduced GO in multiple grades, graphene nanoplatelets, and CVD graphene films — each with published characterization. Industrial & composite CNT masterbatches and composite additives, conductive inks, and tonnage-scale supply for production, not just the research bench. Proprietary lines Flexiphene surfactant sheets and engineered nanocomposites you will not find in a general materials catalog. What makes a quality nanomaterials supplier A “lowest price” headline tells you nothing about whether the material will work in your study. Independent surveys of commercial graphene have repeatedly found wide variation in flake size, layer count and purity between suppliers — which means reproducibility, not the sticker price, is what protects your grant and your publication. Here is what actually matters, and it is exactly where we compete: 1. Published specifications and characterization data Insist on real data — XPS, Raman, FTIR, TGA, AFM and C:O ratios — not just a one-line generic datasheet. We publish full specifications and representative characterization data, and ship a TDS and SDS with every order. 2. A specification guarantee If the material does not meet its published spec, you should get a replacement or a refund. We guarantee that. Ask any supplier whether they will put the same in writing. 3. Transparent pricing Prices should be visible, not hidden behind a slogan. Ours are listed, with an instant quote in the cart and real volume pricing. 4. The ability to scale Many suppliers stop at research grams. We take you from a few grams of validation material to production tonnage of the same, characterized product. 5. Experience that shows up in your results Twenty-one years of supplying researchers means our materials appear in a large body of peer-reviewed work. Consistency over two decades is hard to fake and impossible to buy with ad spend. Independently verified: we lead the category Across our tracked market keyword set, third-party SEO data ranks Cheap Tubes the #1 most-visible supplier in the category, above 50% visibility — ahead of much larger names — and we hold the #1 organic position for high-intent searches such as “best SWCNT supplier” and “99.5 purity SWCNT.” Researchers find us because, for two decades, our materials have performed in their work. A note to competitors We have no problem being compared — we welcome it, because the facts favor our customers. Bidding on the Cheap Tubes name and trademark is a different matter. We monitor brand bidding and trademark use continuously, and we respond with a public comparison like this one, with trademark complaints to Google where our mark appears in ad copy, and by competing harder on the only things that matter to a researcher — quality, data, price, and 21 years of doing right by them. Compete with us on the merits. You will find that the harder game. Questions buyers ask Is Cheap Tubes a good alternative to ACS Material? Yes — for carbon nanotubes, graphene and graphene oxide, Cheap Tubes is a direct, lower-cost, fully-characterized alternative, in business since 2005. Is Cheap Tubes cheaper than ACS Material? At volume, yes. Our graphene oxide starts around $90/g and our MWCNT pricing falls below $1/g at volume; ACS lists graphene oxide from about $135 and MWCNT from about $120/g (publicly listed prices as of June 2026 — confirm current pricing on each site). Does Cheap Tubes provide characterization data and a guarantee? Yes — full published specifications plus representative XPS, Raman, FTIR, TGA and AFM data, a TDS + SDS with every order, and a guarantee that material meets its published specification or is replaced or refunded. What carbon nanomaterials does Cheap Tubes supply? SWCNTs and MWCNTs, functionalized/graphitized/helical/short CNTs, graphene oxide and rGO, graphene nanoplatelets, CVD graphene films, fullerenes, MXene, silver nanowires, nano inks, Flexiphene sheets and engineered nanocomposites. Compare us for yourself See full specs, published characterization data, and live pricing — or ask us anything. Browse Cheap Tubes → *Representative pricing shown for illustration; confirm current pricing on each supplier’s website. Comparison reflects publicly available information as of June 2026. Company names and trademarks are the property of their respective owners; this comparison is provided for informational purposes.