Effective Reduction of Oxygen Debris in Graphene Oxide

Abstract

Graphene oxide (GO) raised substantial interest in the last two decades thanks to its unique properties beyond those of pristine graphene, including electronic energy bandgap, hydrophilic behavior and numerous anchoring sites required for functionalization. In addition, GO was found to be a cheap mass-production source for the formation of the pristine graphene. However, the presence of numerous clusters containing oxygen functional groups (called debris) on the GO surface hinders the GO integration in electronic devices.Here, we present a simple method aimed to reduce the density of oxygen debris weakly bonded to the surface. The method consists of minimal treatments, like sonication and/or water rinsing processes. Whereas this simple method removed epoxy and hydroxyl oxygen groups weakly attached to the graphene matrix, the double C=O bonds are almost not affected by the applied treatment, as demonstrated by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Scanning tunneling microscopy and high-resolution transmission electron microscopy measures designated non-uniform distribution of the oxidation sites, appearing as clusters concentrated preferentially on GO defected regions, albeit separated by pristine graphene areas. The results should have an impact in the implementation of GO in electronic devices deposited on different substrates.

From graphene to graphene oxide: the importance of extended topological defects

“…Please do not adjust margins the OD preferentially complexes to the disordered regions, as others have suggested. 62 Finally, areas highlighted in green show no contrast, and are assigned to holes in the graphene sheet. Again, we expect that the holes are not caused by basewashing per se, but rather that they are hidden by the OD coverage on the aGO.…”