Optoelectronic properties of graphene thin films prepared by thermal reduction of graphene oxide

Graphene thin films have been prepared by thermal reduction of graphene oxide. Raising the reduction temperature results in a red-shift of the G peak in Raman spectra. The reduction temperature turns out to strongly affect the morphology of the prepared graphene film. Photoluminescence (PL) results show that the band gap of graphene can be tuned by varying the reduction temperature. The thermal reduction process has been optimized in an effort to minimize the formation of wrinkles/folds on the graphene surface leading to enhanced PL and Raman peak intensities and reduced electrical sheet resistance. (C) 2010 Elsevier B.V. All rights reserved.