Synthesis and characterization of CuO/Ni₇S₆ composites for application in supercapacitors

Copper oxide (CuO) is considered a promising material for pseudocapacitor electrodes in supercapacitors. In this study, binder-free CuO/Ni₇S₆ composite electrode materials were prepared on nickel foam using a two-step electrodeposition method. The test results show that the CuO/Ni₇S₆-1:1-20 composite material has the best electrochemical performance. It displays an areal capacitance of 8644.3 mF cm⁻² at a current density is 1 mA cm⁻². The assembled CuO/Ni₇S₆-1:1-20|PVDF/KOH|CuO/Ni₇S₆-1:1-20 devices can reach a maximum energy density (E_a) and power density (P_a) of 112.5 μW h cm⁻² and 4200 μW cm⁻² respectively while retaining 58.3% of their initial capacitance after 3000 charge/discharge cycles. Two devices connected in series can power an LED lamp for up to 15 minutes. The results demonstrate that CuO/Ni₇S₆ materials have significant potential for application in supercapacitors.