Nano, nano

An electron microscope image of a hybrid structure made from a gold nanowire (middle) and carbon nanotubes.

But the marriage of carbon nanotubes and metal nanowires could put the structures in computer chips, displays, sensors, and other electronic devices, say researchers at Rensselaer Polytechnic Institute.

The Rensselaer technique deposits copper or gold wires inside the nanoscale pores of an alumina template. The assembly goes in a furnace that has a carbon-rich atmosphere. High temperatures cause the carbon atoms to arrange themselves along the channel wall of the template. Carbon nanotubes then grow directly on the copper wires. The approach lets researchers manipulate and control the junctions between nanotubes and nanowires over a length of several hundred microns.

To date, the team has made hybrid nanowires of carbon nanotubes with both copper and gold. They are also working to connect carbon nanotubes to a semiconductor, which could form a diode. The alumina templates come from the filter industry, so scaling up the technique should be straightforward.