Preparation, characterization, and supercapasitive properties of CoO-NiO microflowers incorporated with graphene oxide and reduced graphene oxide hybrid materials

Abstract

This research investigated the preparation, characterization and supercapacitive properties of cobalt oxide-nickel oxide (CoO-NiO) microflowers incorporated with graphene oxide (GO) and reduced graphene oxide (RGO) nanosheets. These hybrid materials were easily prepared through a direct mixing of CoO-NiO powder suspended in acidic solution with the appropriate amount of GO and RGO loading to make CoO-NiO/GO and CoO-NiO/RGO hybrid samples, respectively. Then, the obtained hybrid samples were characterized by X-ray powder diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques. The results demonstrated that the crystalline phases and functional groups of all hybrid samples are corresponding to pristine CoO-NiO and RGO. SEM results showed that the CoO-NiO microflowers were impregnated and well-combined with both GO and rGO nanosheets. Moreover, the supercapacitive behavior of pristine CoO-NiO and all hybrid samples were studied using cyclic voltammetry (CV) technique. The results revealed that all hybrid samples exhibited much higher the current density than those of the bare CoO-NiO. Thus, this research indicates that the supercapacitive properties of CoO-NiO incorporated with both GO and RGO hybrid materials are superior to the pure CoO-NiO microflowers.