Electrolytic method could fulfil carbon nanotube potential

A team at Cambridge University is investigating whether nanotubes made with the new method could be used to improve the energy density of lithium-ion batteries for electric vehicles.

The unique electrical and mechanical properties of carbon nanotubes mean they could have wide-reaching applications for a number of industries. However, costs are still prohibitive — currently in the region of $1,000(£610)/kg — meaning that, on balance, existing materials generally have the edge in terms of cost and function. Indeed, total worldwide production of carbon nanotubes is only around 1,300 tonnes a year.

One of the reasons behind this is the method used to produce the material, which essentially involves growing nanotubes from a hot, carbon-rich vapour in the presence of expensive catalysts. It has poor throughput, yield and selectivity.

A team headed by Prof Derek Fray, director of the Department of Materials Science and Metallurgy at Cambridge, has been experimenting for some years with a new technique to produce nanotubes directly from readily available graphite using an electrolytic process.