IN THE past ten years or so, the remarkable electrical and mechanical properties of carbon nanotubes have captured the attention of researchers worldwide. This is largely because these novel structures could lead to a huge range of potential applications worth billions of dollars. These range from nanoscale electronics and tools to manipulate individual atoms, to exceptionally strong materials, flat-panel displays and hydrogen fuel cells.
However, to turn nanoscience into a technology, we need to be able to grow carbon nanotubes and fabricate nanometre-sized devices on a large scale. We also need a thorough understanding of the properties of nanotubes. Early efforts to characterize carbon nanotubes were hindered by the inability to make sufficiently pure samples, and the difficulty in assembling "addressable" structures from individual nanotubes.
In the future, integrated circuits that have components or wires made from nanotubes will unavoidably rely on some sort of chemical "self-assembly" in which the chemical properties of the constituent molecules cause them to form regular structures, or on methods to control the growth of nanotubes on surfaces. Developing these chemical approaches will undoubtedly benefit fundamental studies of quasi-one-dimensional systems and their practical applications.
In the June issue of Physics World magazine, Hongjie Dai from Stanford University writes about the latest research on the growth of nanotubes.