Preparation and characterization of Bi12TiO20/RGO as high-efficiency photocatalysts for degradation of dye wastewater

Bi12TiO20/reduced graphene oxide (RGO) composites were successfully synthesized by combining sol-gel method with hydrothermal treatment. The TEM showed that Bi12TiO20 nanoparticles are well dispersed on the surface of graphene. The photocatalytic performance of Bi12TiO20/RGO composites was evaluated by degrading Rhodamine B (RhB) to innocuous substance under the visible light. The degradation rate of RhB over Bi12TiO20/RGO3 composites can reach 98%, which is much higher than Bi12TiO20. The introduction of graphene enhances the charge transfer ability and effectively inhibits the recombination of photogenerated electrons and holes. Bi12TiO20/RGO composites exhibit good stability in cycling experiments. The ∙OH and h+ generated in the Bi12TiO20/RGO-photocatalyzed RhB degradation system are identified as active species by free radical and hole scavenging experiments and the photocatalytic degradation mechanism is proposed.