Enhanced capacitance of unexfoliated graphite oxide by coupled electro-deoxidation/functionalization in an alkali solution

Unexfoliated graphite oxide (GO) was electrochemically reduced in an alkali solution and the electrochemical oxidative functionalization of electrochemically reduced graphite oxide (ERGO) was achieved by applying a more positive potential than the open circuit potential (OCP) in an alkali solution such as KOH, NaOH or LiOH. Such a method highly increased the specific capacitance of the GO. The electrochemically reduced and functionalized GO exhibited a relatively high cation adsorption capacitance of about 140F/g. The results indicate that coupled electro-deoxidation/functionalization is a simple, fast and efficient method to improve capacitance, especially the cation adsorption capacitance of reduced GO.