Hydrothermal synthesis of CuCo2O4/CuO nanowire arrays and RGO/Fe2O3 composites for high-performance aqueous asymmetric supercapacitors

Abstract

The applications of traditional asymmetric supercapacitors are restricted due to the low specific capacitance of carbon negative materials. The rational design of positive and negative electrodes that afford high-performance asymmetric devices is particularly important. In this paper, we fabricate a cost-effective, environmental-friendly aqueous asymmetric supercapacitor by using CuCo₂O₄/CuO nanowire arrays as the positive electrode and RGO/Fe₂O₃ composites as the negative electrode. The assembled device exhibits a high energy density of 33.0 W h kg⁻¹ at a power density of 200 W kg⁻¹, and it still operates at a high power density of 8.0 kW kg⁻¹ with an energy density of 9.1 W h kg⁻¹. The current strategy will provide a fresh route for the design and fabrication of novel asymmetric supercapacitors with high energy density and high power density.