Facile synthesis of graphene oxide hybrids bridged by copper ions for increased conductivity

Abstract

In this article, we report a facile method for preparing graphene oxide (GO) hybrid materials consisting of copper ions (Cu²⁺) complexed with GO, where Cu²⁺ acted as bridges connecting GO sheets. The method of film formation is based on cross-linking GO using Cu²⁺ followed by filtration onto nanoporous supports. This binding can be rationalized due to the chemical interaction between the functional groups on GO and the metal ion. We observed that there was a decrease in charge transfer resistance through electrochemical study. It suggests that the presence of metal ions in GO films could introduce new energy levels along the electron transport pathway and open up possible conduction channels. We also found that the hybrid graphene film assembled with Cu²⁺ dramatically decreases resistance through flash light reduction.