(217et) Preparation of Reduced Graphene Oxide-MnOx Composites By Anodic Deposition and Their Supercapacitive Behaviors

A supercapacitor, also called electric double layer capacitor (EDLC) is a device that utilizes the electric charge accumulated in the electric double layer that occurs between the solid electrode and the electrolyte. Supercapacitors have advantages of high power density, long clycle lif and so on. Graphene oxide sheet (GOS) and graphene nano sheets (GNS) have attracted research interest as electrode materials for supercapacitors because of their large surface area and good conductivity. In this study, the electrochemical prosperities of a reduced graphene oxide (RGO)-MnO_X composite as the electrode materials for enger storage devices have been investigated in KOH solution. The working electrode was fabricated by an anodic deposition of MnO_X onto RGO electrode. The anodic deposition was carried out in 0.4M KMnO₄ electrolyte by chronoamperomety method using a platinum foil counter electrode and an Ag/AgCl reference electrode. The prepared RGO-MnO_X composite was characterized by a scanning electron microscope (SEM), an X-ray photoelectron spectroscopy (XPS) and so on. The electrochemical tests such as cyclic voltammetry (CV), galvanostatic charge-discharge technique and electrochemical impedance spectroscopy (EIS) were performed in 1M KCl solution. The nanosized MnO_X was successfully deposited on RGO and the measured specific capacitance of the RGO-MnO_X composite exhibits about 220F/g.