Preparation and Electrochemical Properties of NiCo2O4/rGO Composites

Abstract

NiCo2O4/rGO as electrode materials for supercapacitor were prepared by a facile hydrothermal route and co-precipitation. XRD and SEM were used to determine the lattice characteristics and morphology of NiCo2O4/rGO nanocomposite. It was found that GO had a good lamellar layer structure, and the overall structure was a flower-like structure. NiCo2O4 in the two methods is uniformly attached to the surface of rGO. The shape of NiCo2O4/rGO nanocomposites prepared by solvothermal method (S-NiCo) after composite is similar to that of sea urchin, and the gap distribution between needles is reasonable. The NiCo2O4/rGO nanocomposites prepared by coprecipitation method (C-NiCo) have three-dimensional network structure, and the nanocomposites are oriented. Using calomel electrode as reference electrode, a three electrode system was constructed for electrochemical experiments. The specific capacitance of NiCo2O4/rGO prepared by coprecipitation method is 1063.5F/g, that of NiCo2O4/rGO prepared by solvothermal method is 935.6F·g−1, and that of NiCo2O4 prepared by coprecipitation method is 913.4F·g−1 by constant current charge discharge test at 2A·g−1. The resistance measured by the AC impedance experiment is 1.13Ω, which is less than 1.35Ω of NiCo2O4/rGO electrode material prepared by solvothermal method.