tWe present an innovative approach for synthesis of zinc oxide–graphene (ZnO–G) hybrid nanostructuresthrough combination of improved hummer and arc discharge methods in liquid. A detailed study of theconsiderable visible-light photocatalytic activities of these nanostructures for the degradation of Phenolred (PR) and Methyl orange (MO) as standard organic compounds under the irradiation of 90 W halo-gen light for 2 h has been performed. The ZnO–G nanostructures were characterized by X-ray diffraction(XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer EmmettTeller (BET) and ultra violet–visible absorption spectroscopy (UV–vis). The results revealed that theZnO–G nanostructures extended the light absorption spectrum toward the visible region and remarkablyenhanced the photodegradation of standard dyes under visible-light irradiation. It has been confirmedthat the ZnO–G nanostructures could be excited by visible-light (E ∼ 2.6 eV). The major enhancement inthe photocatalytic activity of ZnO–G nanostructures under visible-light irradiation can be attributed tothe effect of electron transport among ZnO nanoparticles (NPs) and graphene sheets. A mechanism forphotocatalytic degradation of organic pollutants over ZnO–G photocatalyst was proposed based on ourobservations.
