Pumping Carbon: Researchers watch nanofibers grow
By Peter Weiss
Carbon nanotubes only a few atoms in diameter could become the basis of important new technologies ranging from molecular-scale transistors to elevators capable of ascending to space. Yet longstanding uncertainties about how nanotubes and other ultrathin carbon fibers grow are slowing efforts to realize such visions (SN: 10/5/02, p. 218: Ribbon to the Stars). That knowledge gap has also stymied engineers trying to prevent the unwanted formation of nanoscale carbon whiskers in various industrial chemical processes where the fibers inactivate catalysts.
Now, a team of researchers in Denmark has made atomic-scale movies of the formation of carbon nanofibers. This most-detailed-ever look at the growth of such filaments bucks the prevailing wisdom about atomic migrations during the process. It also reveals unexpected behaviors of the metal catalysts, such as nickel, that facilitate fiber development.