The Various Carbon Nanotubes Applications

There are several carbon nanotubes' applications that take full advantage of their unique properties such as their mechanical strength, thermal conductivity, electrical conductivity and aspect ratio. Let's throw light on some of them as follows:

Carbon nanotubes' uses in creation of lighter conductive plastics

Plastics for long have been used as a temporary replacement for metal. Though they've made inroads into structural applications, but not when it comes to electrical conductivity as they're good electrical insulators.

The deficiency of electrical conductivity in plastics is generally overcome by heavily loading them up with graphite and carbon black fibres, leading to an increase in their weight.

This is where the carbon nanotubes come into the picture. They've the highest aspect ratios among all carbon fibres, thus requiring lower loading in order to achieve the desired level of electrical conductivity in plastics. Hence some of the carbon nanotubes' uses are in creation of

  • EMI/RFI shielding composite and coatings for gaskets, enclosures etc.
  • Electrostatic dissipation or ESD
  • Radar-absorbing materials and
  • Antistatic materials

Applications of carbon nanotubes in molecular electronics

One of the key components of nanotechnology is creation of electronic circuits using molecules. The inter-connections between the switches and other active devices becomes highly critical as the dimensions get reduced to nano-scale in electronic circuits.

Carbon nanotubes are the ideal mediums for such connections in molecular electronics owing to their electrical conductivity and geometry. Furthermore, they're also actively used as switches.

Applications of carbon nanotubes in field emissions

Owing to their unparalleled tip sharpness and high electrical conductivity, carbon nanotubes are the best field emitters of any material. Their extremely sharp tips also leads to emission of very low voltage, something that's highly relevant in devices, which can benefit from such feature. Carbon nanotubes can carry very high current density with extreme stability.

One of the immediate applications of carbon nanotubes in this regard is in flat panel displays. Rather than using the conventional cathode ray tube display with a single electron gun, one or many electron guns can be used for every pixel in the display. Few other applications of this field emission characteristic of nanotubes are in lightning arrestors, electron microscope sources and cold-cathode lighting sources.

Some of the other applications of carbon nanotubes

Thermal materials - Carbon nanotubes' anisotropic thermal conductivity is highly useful in applications where the heat must be moved from one location to the other, for example, in case of electronics, especially advanced computing where it's normal for chips to reach 100°C or higher temperatures. Nanotubes' composites are showing great promise in dramatically increasing bulk thermal conductivity, even at small loadings.

Energy storage - Carbon nanotubes' intrinsic characteristics are easily utilised in the form of electrodes in capacitors and batteries. They've even found applications in various types of fuel cell components. Some of the unique properties of CNTs make them useful in the form of electrode catalyst supports in the PEM fuel cells too. Furthermore, their high electrical conductivity makes them useful in current collectors and gas diffusion layers as well.

Fibers and fabrics - Rapid research and development work is underway in production of fibres and fabrics from carbon nanotubes, apart from production of CNT composite fibres. These highly strong fibres have applications in textiles, transmission line cables, vehicle armour, body armour and woven fabrics.

Structural composites - CNTs don't just have amazing thermal and electrical conductivities, their mechanical properties like their strength, toughness and stiffness are commendable too, making them applicable in advanced composites needing high values of one or more of these properties.

Other applications of carbon nanotubes

Some of the other carbon nanotubes' applications are:

  • In the form of catalyst supports
  • In biomedical applications such as in the form of coatings for prosthetics, vascular stents, neuron regeneration, neuron growth and more
  • As nanoporous filters
  • As solar collectors
  • As conductive connectors and adhesives