Hybrid of cerium dioxide nanoparticles/reduced graphene oxide as an electrode material for supercapacitor applications

In this study, we prepared cerium oxide (CeO2) hybridized with reduced graphene oxide (rGO) nanosheets using the hydrothermal method. CeO2 and CeO2/rGO were evaluated as electrode materials for use in supercapacitor applications. The structure and morphology of the synthesized materials were investigated. Cyclic voltammetry tests determined a high specific capacitance of 581 F g(-1) for CeO2/rGO at a scan rate of 10 mV s(-1) in 2 M KOH. In addition, the CeO2/rGO electrode retained 91 % of its initial capacitance after 5000 consecutive cycles, thereby indicating its excellent electrochemical stability. The excellent stability of CeO2/rGO was due to a synergistic effect between CeO2 and rGO. CeO2 nanoparticles decorated on rGO facilitated the migration of electrolyte ions and provided electroactive sites for the faradic process. The rGO nanosheets increased the conductivity of the composite and enhanced its electrochemical stability.