SYNTHESIS AND CHARACTERIZATION OF GRAPHENE OXIDE FOR USE IN ELECTROCHEMICAL CAPACITOR

Abstract

Graphene is a monolayer with a hexagonal structure of carbon atoms and has become a material of great interest to researchers in nanotechnology and nanoscience. In this paper the viability of the application of both oxidized and reduced graphene for use as electrodes in electrochemical capacitors was analyzed. The synthesis of graphene oxide was obtained through the modified method of Hummers-Hoffmann and later the chemical and thermal reduction of this material. The materials were characterized by X-ray Diffraction (XRD), Infrared Spectroscopy and Raman Spectroscopy. Analysis by XRD showed a little exfoliation for the graphene oxide with as precursor the graphite. The results of infrared spectroscopy showed oxygen groups that were inserted in the oxidation process, corroborated by the Raman spectroscopy technique. Synthesized graphene was analyzed by Raman spectroscopy and showed multi-sheet graphene. The electrodes obtained were characterized by the cyclic voltammetry technique and the voltammograms showed that graphene oxides presented better results as an electrochemical capacitor, compared to the reduced graphene, evidencing that the incorporation of oxygen groups on the surface of the oxide improved the formation of the layer electric double.