Hydrothermal synthesis of graphene oxide-modified zinc oxide nanoplate composites with enhanced photocatalytic activity for degradation of rhodamine B under visible light

A nanocomposite of zinc oxide nanoplates with graphene oxide (GO-ZnO) was chemically synthesized using a facile and cost-effective approach by the hydrothermal method. The structure, morphology, composition, and photoactivity of the composites were studied by XRD, SEM, TEM, EDAX, XPS, LSV, and EIS. The characterization results show that GO-ZnO nanoplate composites can be used as efficient photocatalytic agents. The photocatalytic activity of GO-ZnO nanoplate composites was investigated for the degradation of an organic dye rhodamine B (RhB) under visible light (sunlight) irradiation, and the degradation efficiency was found to be 93.74%. The mechanism of RhB degradation by composite has been proposed, showing that the synergistic effect of ZnO and GO plays a crucial role by reducing the electron-hole recombination rate and increasing the charge transfer rate in the composite polycrystalline structure, resulting in a highly efficient photocatalytic performance. The degradation kinetics follow a pseudo-first-order reaction in the presence of sunlight.