Researchers at the Honda Research Institute, Purdue University and the University of Louisville have discovered a way to systematically grow carbon nanotubes with either metallic or semiconducting properties, solving a long-standing problem in nanotechnology research and paving the way for the widespread use of nanotubes in electronics.

Nanotubes are one-atom thick sheets of carbon rolled up in a cylindrical form, and come in two types: metallic and semiconducting. Metallic nanotubes are about 100 times stronger than steel while significantly lighter and stronger; semiconducting nanotubes, on the other hand, are among the best electrical conductors ever discovered.

When combined, these two kinds of nanotubes could be used as the basic building blocks to produce the next generation of transistors, as well as bringing important improvements to a number of fields including solar and battery technology.

Carbon nanotubes have been the object of intense research since they were discovered in the early 90s, but they need to be manufactured according to very specific standards in order to be employed successfully — this is particularly true with metallic nanotubes and has been a major obstacle to their effective employment so far.