Carbon nanotubes, often abbreviated as CNTs, are very small allotropes of carbon, with dimensions in the range of few nanometers or lower, which have properties that make them very much suitable for a number of applications
It has an enormously high tensile strength and they have a very high electrical conductivity along with other advantages such as the ability to withstand high temperatures and other extreme conditions.
As for physical strength, it has been shown that potentially they can reach a modulus up to 1TPa, which would put them much beyond the limits of steel or other high-toughness materials available today
However, such theoretical properties have not been fully achieved yet, with current production methods such as CVD or spinning being able to produce them with substantially lower strength properties. Currently carbon nanotube-based yarns have been demonstrated with strengths of 10 GPa but having defects in the structure bringing down such value to 1GPa in real world applications
While the production of carbon nanotubes has so far proven expensive, they are making a slow but steady advance in many fields such as medicine, military, automotive field, in the construction and electronics business among others.
So far, they have been also successfully adopted in small quantities in carbon fibers for the production of tennis rackets, baseball bats, automobile parts and for other mission-critical tools where strength and light weight are needed.
The issue of high cost has been so far the stumbling block preventing widespread adoption of carbon nanotubes for a range of applications, but efforts made by some major players such as Arkema S.A., CNano Technology Ltd., Hyperion Catalysis International Inc., are driving prices down and this may further increase their adoption for new applications, such as adoption in the IC market or in the MEMS market.
For example, new potential applications in the IC market are most interesting as IC based on CNTs, also known as carbon nanotube field-effect transistors, have been demonstrated to operate at room temperature and being able to switch using only one electron. Since the year 2000, several IC components have been developed, such as: nanotube-based transistors, nanotube-based memory components, nanotube-based memory switches; density of such components, however, is not even remotely comparable to today silicon-based ICs.
Another future big market for CNTs may be the solar market, as they have shown the interesting property of being able to absorb infra-red light and therefore being able to increase the efficiency of classic silicon-based solar cells.
Finally, they may have yet another potential application in hydrogen storage, as they have the property to allow molecules of condensed gases being stored inside a single walled CNT.
Geographically wise speaking, the major growth in year 2012 in their utilization has been in the Asia-Pacific and United States markets, due to an increase of number of applications in the electronics and other semiconductor markets.
As of today, main players in the CNTs market are Nanocyl S.A. of Belgium, Showa Denko K.K. of Japan in addition to the companies already mentioned above: Arkema of France, CNano Technology Ltd. and Hyperion Catalysis International Inc. of the US.
About the Author-
This article was written by Matteo Martini, author and CEO of Martini Tech, a company that provides Nano imprinting, PSS patterning, MOCVD deposition, sputtering, MEMS foundry, GaN wafer, GaN LED Technology and other microfabrication-related services. Please have a look at our blog.