Hierarchical CuCo2O4@NiMoO4 core–shell hybrid arrays as a battery-like electrode for supercapacitors

Abstract

Herein, hierarchical CuCo₂O₄@NiMoO₄ core–shell nanowire arrays were successfully synthesized on Ni foam via hydrothermal processes as a battery-like electrode. Owing to the unique core–shell structure and the synergetic effect from CuCo₂O₄ and NiMoO₄, the resulting CuCo₂O₄@NiMoO₄ core–shell arrays exhibit a high specific capacitance of 2207 F g⁻¹ at 1.25 A g⁻¹ and good rate capability with only about 4.4% capacitance loss after cycling tests. Furthermore, we assemble the corresponding asymmetric supercapacitor using CuCo₂O₄@NiMoO₄ (positive electrode) and activated carbon (negative electrode), which delivers a high energy density (about 40 W h kg⁻¹) and good cycle stability. Thereby, these electrochemical performances demonstrated that as-fabricated CuCo₂O₄@NiMoO₄ core–shell arrays are promising candidates as electrodes for high-performance supercapacitors.