Scientists at Rice University have developed a cable made from carbon nanotubes that will serve as an energy-efficient electric grid.
Rice chemist Andrew R. Barron, author of a paper about the latest innovation stated that armchair quantum wire (AQW), with the capacity to carry current over long distances with minimal loss, will soon replace copper-based wires, which loses power at 5 % for every 100 miles of transmission. Details about this innovation were recorded online in the journal Nano Letters published by the American Chemical Society.
The paper was written by undergraduate student Andrew Owens and Barron, graduate student Alvin Orbaek, and a professor of materials science. Barron stated that a primary challenge in this innovation is the manufacturing of huge quantities of metallic single-walled carbon nanotubes. Armchairs are capable of carrying electricity, but they have to be manufactured in batches along with other types of nanotubes and have to be drawn out separately.
Barron's lab showed how to significantly elongate tiny groups of individual nanotubes. Under ideal conditions, long armchair nanotubes could be slashed, re-treated with catalyst and re-grown for an indefinite period. The researchers observed that amplification of nanotubes was a crucial step for manufacturing AQW.
Orbaek ensured to attach an iron/cobalt catalyst chemically to the tips of nanotubes and then fine-tuned the atmosphere and temperature surrounding the amplification. Barron stated that in the initial demo, they could evolve only a single tube from hundreds or thousands of nanotubes. In the experiments following the initial one, they could increase the yield, but the growth of tubes was minimal. He claimed that the catalyst would etch the nanotubes.
Barron said that up to 90 % of the nanotubes present in a group can now be grown to considerable lengths. The researchers conducted the recent experiments on single-walled carbon nanotubes, but they feel that the results would be better when a group of pristine armchairs are used. The first growth happened at 1,000ºC. The researchers, during amplification, had to decrease the temperature to 200º and to regulate the chemistry to increase the yield. Barron and his team are working to fine-tune the process and hope to start amplification of armchair nanotubes to manufacture huge numbers of pure metallics.
Source: http://www.rice.edu/