Ni₃Se₂thin films deposited on CuO nanomaterials as electrode materials for supercapacitors

With the ever-increasing demand for high-performance energy storage devices, the development of efficient and stable electrode materials for supercapacitors has garnered significant attention. Although CuO has a high theoretical specific capacitance, its poor conductivity and cycling performance limit its application. In this study, low-resistance nickel selenide (Ni₃Se₂) nanostructures were fabricated on the surface of copper oxide by electrodeposition, and the synergistic effect of the two was utilized to enhance the overall electrochemical performance of the electrode. The results exhibit that CuO@Ni₃Se₂ attains a specific capacitance up to 1488.0 mF cm⁻² at a current density of 1 mA cm⁻², with a cycling stability of 97.4% in 3000 cycles of charge/discharge test. In addition, the solid-state symmetric supercapacitors assembled from CuO@Ni₃Se₂ have energy and power densities of 60.5 μWh cm⁻² and 3757.7 μW cm⁻², respectively. The device successfully provided 10 minutes of power supply for an LED lamp, indicating that it has certain application potential in practical applications.