Synthesis of hierarchical Co3O4@NiCo2O4 core-shell nanosheets as electrode materials for supercapacitor application

Construction of core-shell heterostructures with multifunctionalities has been regarded as promising materials to improve the supercapacitor performances for single metal oxide. In our work, hierarchical Co3O4@NiCo2O4 core-shell nanosheets are successfully fabricated on Ni foam for supercapacitors. The Co3O4@NiCo2O4 electrode demonstrates excellent supercapacitor performances with the areal capacitance of 1.33 F/cm2 at 3 mA/cm2, the specific capacitance of 1330 F/g at 3 mA/cm2 and superior cycling stability of ∼100.7% after 5000 cycles. The excellent electrochemical properties for the Co3O4@NiCo2O4 hybrid composites can be ascribed to the unique core-shell nanostructures as well as the synergistic effect of Co3O4 and NiCo2O4. The as-prepared Co3O4@NiCo2O4 hybrid composites with enhanced performances could be considered as a promising electrode material for high-performance supercapacitors.