Characterizations of in situ grown ceria nanoparticles on reduced graphene oxide as a catalyst for the electrooxidation of hydrazine

Abstract

Ceria (CeO₂) nanoparticles were grown on reduced graphene oxide (RGO) via the in situ reduction of graphene oxide (GO) in the presence of cerium nitrate and CTAB, followed by a one step hydrothermal treatment. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), Raman spectroscopy (RS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the samples. The characterization suggests that the ammonia-assisted hydrothermal method is a facile and advantageous route to synthesize CeO₂–RGO nanocomposites compared to the widely used method utilising hydrazine hydrate as the reducing reagent. TEM investigations revealed that the CeO₂ nanoparticles with an average size of ∼14 nm were dispersed on the layers of RGO. The catalytic activity of the CeO₂–RGO nanocomposites towards the electrooxidation of hydrazine was further investigated by cyclic voltammetry measurements. The results obtained suggest that compared to bare CeO₂ nanoparticles, the CeO₂–RGO nanocomposite exhibits remarkably enhanced electrocatalytic activity, due to the synergistic effects between the CeO₂ nanoparticles and RGO.