Graphene production via electrochemical reduction of graphene oxide: Synthesis and characterisation

A considerable amount of research has been devoted to the synthesis of graphene materials via graphene oxide (GO) precursor during recent years due to the fact that it is ease in processing, versatile, and scalable for mass production. Nevertheless, GO needs to be reduced in order to recover the unique properties of pristine graphene. Of the various reduction approaches, the electrochemical method provides a facile, fast, scalable, economic and environmentally benign pathway to the production of desirable quality graphene materials. The electrochemical approach can be undertaken via two different routes: the one-step route which involves direct electrochemical reduction of GO in suspension onto the substrate electrode whereas the two-step route requires pre-deposition of GO onto the substrate electrode prior to electrochemical reduction process. This paper first reviews the preparation methods and various properties of graphene oxide. This is followed by a discussion on the working parameters of the two different electrochemical routes and the associated electrochemical techniques used to produce graphene. This paper also provides reviews on the characteristic properties of the electrochemically reduced graphene through the analysis of various spectroscopic techniques, such as X-ray photoelectron spectroscopy, Raman spectroscopy, infrared spectroscopy, X-ray diffraction and electron microscopic.