When Al3+ meets CuCo2O4 nanowire arrays: An enhanced positive electrode for energy storage devices

Abstract Bimetal oxides have superior supercapacitive properties because of synergistic effect, but their applications are usually limited because of low conductivity. Metal cations doping has been a promising method to break the restriction. Here, we first selected CuCo2O4 nanowire arrays with high electrochemical activity as mother bimetal oxides and Al3+ with high electric conductivity as the dopant to investigate the influence of doped amounts on the electrochemical behaviors. With the increase of doped Al3+, the specific capacitance increased at first and then decreased, in accord with the analysis results of the conductivity, capacitive and diffusion-controlled contribution. The sample with the optimal doping amount had the highest capacitive behavior (1871 F g−1 at 1 A g−1) and considerable cycling performance (93% after 8000 cycles at 2 A g−1). A full button cell consisting of anode material (AC) and cathode material (the optimal Al-doping CuCo2O4) exhibited satisfied energy density (65 Wh kg−1) and power density (735 W kg−1) as well as favorable cycling performance (95% retention after 4000 cycles). A LED was successfully powered by the constructed full cell suggested the promising application in future industrial green energy-storage devices of the Al-doping CuCo2O4 nanomaterials.