Preparation of CeO2-MnO2 Nano-Oxide/Graphene Composite Electrode Materials and Their Performance of Supercapacitor

CeO2-MnO2 nano-oxide/graphene composite electrode materials were prepared by hydrothermal method. The morphology, crystal structure of composite electrode materials and functional group on the surface graphene were investigated by SEM, TEM, XRD and Raman microscopy. And the electrochemical performance of the composite electrode materials was also studied using constant current charging-discharging and cyclic voltammetry (CV). The results indicate that the addition of CeO2 could improve cycle number on electrode cycles. When the mole ratio of cerium to manganese was 2∶8, the best specific capacitance with maximum value of 157 F·g-1 under the scanning speed of 10 mV·s–1 in 1 mol·L-1 Na2SO4 electrolyte, and capacitance loss of 23% after 1 000 cycles of charging and discharging were achieved.