The reduction of graphene oxide by elemental copper and its application in the fabrication of graphene supercapacitor

In this work, graphene oxide (GO) was directly reduced by copper to reduced graphene oxide (RGO) and formed a highly uniform RGO film on copper foil or copper-modified titanium (Ti) substrate. The characterization of as-prepared RGO film by FTIR and XRD indicated that GO was partially reduced by copper while some oxygen-containing groups still remained. The conductivity of the RGO film was improved from 3.76?×?10³ to 2.98?×?10⁴ S/m after it was further electrochemically reduced due to the removal of additional oxygen groups. The graphene supercapacitor prepared with this method exhibited better performances in a neutral aqueous electrolyte compared with that reported for graphene electrodes prepared by other fabrication methods.