Honda Research Institute, in conjunction with researchers at Purdue University and the University of Louisville, have published a report on single-walled carbon nanotubes, in today's edition of Science magazine.
Microscopic carbon nanotubes are 100,000 times thinner than a human hair and may have the potential to transport electricity faster and over greater distances with minimal loss of energy, according to the research.
The findings open new possibilities for miniaturization and energy efficiency, including much more powerful and compact computers, electrodes for supercapacitors, electrical cables, batteries, solar cells, fuel cells, artificial muscles, composite material for automobiles and planes, energy storage materials, and electronics for hybrid vehicles.
Microscopic carbon nanotubes are grown on the surface of metal nanoparticles, taking the cylindrical form of rolled honeycomb sheets with carbon atoms in their tips. When these tiny carbon nanotubes exhibit metallic conductivity they possess extraordinary strength compared with steel, higher electrical properties than copper, are as efficient in conducting heat as a diamond, and are as light as cotton.
Past research efforts to control the structural formation of carbon nanotubes with metallic conductivity through conventional methodology resulted in a success rate of between 25 and 50 percent. Honda, which is one of many companies working in the field of carbon nanotube synthesis, has achieved a success rate of 91 percent metallic conductivity for grown carbon nanotubes.
"This is the first report that shows we can control fairly systematically whether carbon nanotubes achieve a metallic state. Further research is in progress with the ultimate goal to take complete control over grown nanotube configurations to support their real-world application," said Avetik Harutyunyan, principal scientist from Honda Research Institute USA, and the leader of the project.
"Our finding shows that the nanotube configuration, which defines its conductivity, depends not only on the size of the metal nanocatalyst used to nucleate the tube as was previously believed, but importantly also is based on its shape and crystallographic structure, and we learned to control it," Harutyunyan said.