08 March 2011
08 March 2011
New research from the University of Pennsylvania has demonstrated a more consistent and cost-effective method for making graphene.
A Penn research team has been able to create high-quality graphene that is just a single atom thick over 95% of its area, using readily available materials and manufacturing processes that can be scaled up to industrial levels.
""I'm aware of reports of about 90%, so this research is pushing it closer to the ultimate goal, which is 100%,"" said the study's principal investigator, A.T. Charlie Johnson, professor of physics. ""We have a vision of a fully industrial process."" Other team members on the project included postdoctoral fellows Zhengtang Luo and Brett Goldsmith, graduate students Ye Lu and Luke Somers and undergraduate students Daniel Singer and Matthew Berck, all of Penn's Department of Physics and Astronomy in the School of Arts and Sciences.
Producing graphene at industrial scales is inhibited by the ability to make meaningful quantities with consistent thinness. One of the more promising manufacturing techniques is CVD, or chemical vapor deposition, which involves blowing methane over thin sheets of metal. The carbon atoms in methane form a thin film of graphene on the metal sheets, but the process must be done in a near vacuum to prevent multiple layers of carbon from accumulating into unusable clumps.
The Penn team's research shows that single-layer-thick graphene can be reliably produced at normal pressures if the metal sheets are smooth enough.
""The fact that this is done at atmospheric pressure makes it possible to produce graphene at a lower cost and in a more flexible way,"" Luo, the study's lead author, said.
This research was supported by Penn's Nano/Bio Interface Center through the National Science Foundation and the group's findings were published on Feb. 10 in the journal Chemistry of Materials.