Carbon Nanotubes (CNT)
Carbon Nanotubes (CNT): SWCNT and MWCNT Types, Functionalisation and Applications
A carbon nanotube is a graphene sheet rolled into a tube a few nanometres across. Its strength, conductivity and high aspect ratio make CNTs widely used in batteries, composites and sensors.
- SWCNT ≈ 1–2 nmsingle-wall diameter
- -COOH, -OH, aminefunctionalisation options
- Powder, dispersion, arraysincluding buckypaper
- Research scaleavailable at AMI Scientific
What are carbon nanotubes?
Picture a single graphene sheet rolled into a seamless tube: that is a single-walled carbon nanotube (SWCNT), about 1–2 nm in diameter. When several tubes are nested concentrically like Russian dolls, they form multi-walled carbon nanotubes (MWCNT), which can be tens of nanometres across.
SWCNTs have the most remarkable electrical and optical properties but cost more. MWCNTs are more economical and easier to produce at scale, so they are the most common choice as conductive additives and composite reinforcement. CNTs can also be functionalised with carboxyl (-COOH), hydroxyl (-OH) or amine groups to make them easier to disperse and bond to a matrix or biomolecules.
Choosing a CNT type
| Type | Characteristics | Best for |
|---|---|---|
| SWCNT | ±1–2 nm diameter, high surface area | Transparent conductive films, electronics, sensors |
| Industrial MWCNT | Economical, standard purity | Composites, cement and polymer additives |
| Graphitised MWCNT | More ordered graphitic structure, better conductivity | Battery conductive additive, electrodes |
| -COOH / -OH CNT | Disperses easily in water and polar solvents | Sensors, biomaterials, water-based composites |
| Amine CNT | -NH₂ groups for covalent bonding | Epoxies, biomolecule immobilisation |
| Arrays and buckypaper | CNTs aligned on substrates or as free-standing sheets | Field emission, membranes, free-standing electrodes |
Carbon nanotube products
Selected Nanografi products. Some products share a name but differ in size or purity; check each product page.
| Product | Best for | Price | Purchase |
|---|---|---|---|
| SWCNT 1–2 nm | Electronics and sensor research | Rp 7.273.000 | Buy online |
| Large-surface-area SWCNT | Supercapacitor electrodes, adsorption | Rp 8.241.000 | Buy online |
| -COOH functionalised SWCNT | Biosensors and aqueous dispersions | Rp 5.338.000 | Buy online |
| Graphitised MWCNT | Conductive additive for battery electrodes | Rp 3.751.000 | Buy online |
| -COOH graphitised MWCNT | Electrochemical sensor electrodes | Rp 4.448.000 | Buy online |
| -COOH industrial MWCNT | Composites and larger-scale research | Rp 2.668.000 | Buy online |
| Amine MWCNT | Epoxy composites, biomolecule immobilisation | Rp 7.118.000 | Buy online |
| MWCNT isopropanol dispersion | Direct coating without long sonication | Rp 7.660.000 | Buy online |
| CNT buckypaper | Free-standing electrodes and membranes | Rp 7.505.000 | Buy online |
See everything in the carbon nanotube search.
Applications and usage tips
- Conductive additive in lithium battery cathodes and anodes, often combined with carbon black.
- Glassy carbon electrode modification for electrochemical sensors.
- Reinforcement of polymer, cement and metal composites.
- Disperse with sonication and a surfactant such as SDS or Triton X-100; functionalised CNTs disperse more easily in water.
- Purify or check residual metal catalyst if your application is sensitive to metal impurities.
- CNTs are fibrous nanopowders; avoid inhalation and use personal protective equipment.
Usage notes
Products are for research and laboratory use only, not for consumption or as finished cosmetic ingredients. Full specifications and SDS are on each product page.
Frequently asked questions
What is the difference between SWCNT and MWCNT?
SWCNTs have a single graphene wall about 1–2 nm across; MWCNTs have several concentric walls and a larger diameter. SWCNTs excel in electronics, MWCNTs are more economical for composites and batteries.
Why choose functionalised CNTs?
-COOH or -OH groups make CNTs easier to disperse and able to bond to polymers or biomolecules, which helps sensors and water-based composites.
How much CNT goes into a battery electrode?
Usually just a few weight percent depending on the formulation; many studies combine CNTs with carbon black. Optimise with EIS and rate-capability tests.
Need help choosing?
Tell us about your samples, methods and budget. Our team will put together the equipment and supplies with a formal quotation.
