By Weiss, P.
Science News , Vol. 170, No. 16
Nanoscale tubes of carbon could potentially lead to novel technologies, such as electronic circuits that are much faster and more compact than those made today. However, the batches of carbon nanotubes that manufacturers now produce are difficult to use because they contain a hodgepodge of tubes of varying electronic properties and diameters.
Now, researchers have devised a way to sort these nanotubes. The technique could clear a major obstacle to industrial-scale application of the tubes in circuits, sensors, computer screens, and other products, say Michael S. Arnold and his colleagues at Northwestern University in Evanston, Ill.
The new approach is "a landmark breakthrough," comments nanotechnologist and chemist Ray H. Baughman of the University of Texas at Dallas.
"This method is surely going to accelerate the process for developing real applications of nanotubes," adds chemist Jie Liu of Duke University in Durham, N.C.
The atomic structures of carbon nanotubes enable some of them to serve as semiconductors in nanoscale transistors (SN: 9/10/05, p. 165). Other nanotubes behave like metal wires. Nanotubes' diameters also affect their properties.
In previous research, other scientists had devised ways to separate carbon nanotubes. However, those methods required costly additives or had other shortcomings that limited their potential for large-scale use, says Arnold. …