Photocatalytic decomposition of methylene blue using a zinc–tungsten oxide compound prepared by co-sputtering and calcination

Abstract In this study, we investigated the formation and photocatalytic activity of ZnWO 4 /WO 3 bilayer-like composites prepared by co-sputtering and calcination. The tungsten-doping concentration affects crystal formation and photoluminescence, and transmission electron microscopy revealed that WO 3 forms an underlying layer of ZnWO 4 , forming a bilayer-like structure at high tungsten concentrations. We attribute the formation of this bilayer to segregation during deposition, and we found it to have effective photocatalytic activity for the degradation of methylene blue by hetero junction formation.