Electrochemical behaviour of graphene-poly (3,4-ethylenedioxythiophene) (PEDOT) composite electrodes for supercapacitor applications

In this paper, we report on the electrochemical characteristics of graphene-PEDOT composite electrodes. The electrodes were made of indium tin oxide (ITO) substrates by simple processes of electrophoretic deposition of graphene followed by electropolymerization of EDOT monomer. The composite electrode was obtained by electrochemical measurements, a median specific capacitance of 1410 F/g and a median area capacitance of 199 mF cm(-2) at a scan rate of 40 mVs(-1). The composite showed good stability characteristics after repeated scans in cyclic voltammetry and fared much better than a thin film of PEDOT. The thermal stability of the composite is also much superior when compared to the polymer with a weight loss temperature of 350 degrees C for the composite and 250 degrees C for the polymer, respectively. The above electrochemical and thermal behaviours of the composite are correlated to the unique morphology of electrodeposited graphene that provides a conductive and high surface area template for electropolymerization.