RGO–TiO 2 –ZnO composites: Synthesis, characterization, and application to photocatalysis

Chemical approaches to the reduction of graphene oxide (GO) for large-scale production of reduced graphene oxide (RGO) sheets have become a reality, speeding up the availability of graphene. In this work, an RGO–TiO 2 –ZnO composite was synthesized through the hydrothermal reduction of GO in a deionized (DI) water solution containing TiO 2 and ZnO precursors at 180 °C. Morphological and structural characterizations using several techniques are reported. The photocatalytic activity of the synthesized RGO–TiO 2 –ZnO composite is approximately 63% at 120 min under 100 W UV irradiation, which is much higher than that of pure ZnO (11%). The enhanced properties are described in terms of increased light absorption intensity and the reduction of electron–hole pair recombination in the composite owing to the stepwise energy level structure in the composite.