Nanospherical Cu2O/NiO synthesized by electrochemical dealloying as efficient electrode materials for supercapacitors

Abstract In this study, Cu2O/NiO with nanosphere structure has been successfully synthesized by dealloying a copper foil coated with Zn-Cu-Ni alloy films. First, Zn-Ni films were electrodeposited on copper foil. Next, the Zn-Cu-Ni films were produced by annealing and the Cu2O/NiO was obtained after Zn-dealloying and oxidation. Due to the advantage of the tunable nanosphere structure and dealloying synthesis method, Cu2O/NiO has excellent supercapacitor properties, such as excellent cycling stability (94.5% after 5000 cycles) and high specific capacitance (2255.5 mF/cm2 in 1 mA/cm2). These data suggested that this low-cost oxide Cu2O/NiO with nanosphere morphology synthesized by dealloying method could be a promising electrode material for supercapacitors.