Binder-free hydrogenated NiO–CoO hybrid electrodes for high performance supercapacitors

Abstract

Binder-free NiO–CoO hybrid electrodes were directly grown on nickel foam by electrodeposition and subsequent annealing in 5% H₂/95% N₂ gas at 300 °C. Crystal structure, elemental analysis, surface morphology and chemical compositions of the composites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) equipped with an energy dispersive X-ray analysis system. The hydrogenated NiO–CoO hybrid electrodes were evaluated as electrodes for supercapacitors which demonstrated promising electrochemical performance with high specific capacitance, excellent rate capability, and stable cycling.