Novel Ag configurations decorated CuO hybrid electrode for high-performance asymmetric supercapacitor

In situ integration of highly conductive metals into transitional metal oxide electrodes with enabling fast electron transfer kinetics is a plausible technique for improving electrochemical performances of electrode materials. Herein, for the first time, we demonstrate a rational configuration of conductive Ag flakes (FAg) that directly grown on CuO nanorods by in situ chemical approach. The obtained FAg–CuO hybrid electrode demonstrates a superior specific capacitance of 812 F/g at a current density of 2 A/g which is retained of about 110.37% after 5000 cycles. The solid-state asymmetric supercapacitor (ASC) based on FAg–CuO and active carbon is further fabricated. The ASC device similarly demonstrates remarkable performances with a high energy density of 40.02 Wh/kg at a power density of 1095.8 W/kg and also excellent cycling ability with stable capacitances output beyond 5000 cycles. The obtained superior performances are attributed to the rational Ag configurations which could effectively reduce the interfacial barriers and meanwhile enhance the electron transport and ion diffusion, with achieving the high-efficiency utilization for the active materials during Faradaic redox reactions.