Folding and cracking of graphene oxide sheets upon deposition
Date of this Version9-2011
Surface Science Volume 605, Issues 17–18, September 2011, Pages 1669–1675
Graphene Oxide (GO) sheets, suspended in an aqueous solution, were deposited on freshly cleaved highly oriented pyrolytic graphite (HOPG) and studied using Raman spectroscopy, atomic force microscopy (AFM) and scanning tunneling microscopy (STM). AFM phase imaging shows a distinct contrast between GO and the underlying HOPG substrate. Raman spectroscopy clearly showed the presence of GO sheets on the top of HOPG substrate. The AFM and STM images also reveal wrinkling, folding, and tearing of individual GO sheets after depositing onto an HOPG substrate. We have also observed a distinct cracking of a GO sheet after folding. We attribute this new cracking phenomenon to a weakening of C C bonds during the oxidation of a graphene sheet. (C) 2011 Elsevier B.V. All rights reserved.
Nanoscience and Nanotechnology