Graphene is a perfect example of the wonders of nanotechnology, in which common substances are scaled down to an atomic level to uncover new and exciting possibilities.
Graphene is created when graphite the mother form of all graphitic carbon, which is used to make the pigment that allows pencils to write on paper is reduced down to a one-atom-thick sheet. Graphene is among the strongest materials known and has an attractive array of benefits. These sheets single-layer graphene have potential as electrodes for solar cells, for use in sensors, as the anode electrode material in lithium batteries and as efficient zero-band-gap semiconductors.
Research on graphene sheets has been restricted, though, due to the difficulty of creating single-layer samples for use in experiments. But in a study published online Nov. 9 in the journal Nature Nanotechnology, researchers from UCLA's California NanoSystems Institute (CNSI) propose a method which can produce graphene sheets in large quantities.
Led by Yang Yang, a professor of materials science and engineering at the UCLA Henry Samueli School of Engineering, and Richard Kaner, a UCLA professor of chemistry and biochemistry, the researchers developed a method of placing graphite oxide paper in a solution of pure hydrazine (a chemical compound of nitrogen and hydrogen), which reduces the graphite oxide paper into single-layer graphene.
Such methods have been studied by others, but this is the first reported instance of using hydrazine as the solvent. The graphene produced from the hydrazine solution is also a more efficient electrical conductor. Field-effect devices display output currents three orders of magnitude higher than previously reported using chemically produced graphene. Kaner and Kang's co-authors on the research were doctoral students Vincent Tung, from Yang's lab, and Matthew Allen, from Kaner's lab.
"We have discovered a route toward
|Contact: Mike Rodewald|
University of California - Los Angeles