Hydrothermal Synthesis of Disk-Like Bi2WO6-BiPO4 Heterojunctions and Enhanced Photocatalytic Performance for Rhodamine B Degradation

Novel Bi2WO6-BiPO4 photocatalysts with heterojunction structure were fabricated through a facile hydrothermal route. The photocatalytic properties of Bi2WO6-BiPO4 composites were evaluated by photocatalytic degradation of rhodamine B (Rh B) under simulated sunlight irradiation. The results showed that Bi2WO6-BiPO4 photocatalysts displayed much higher photocatalytic performances for Rh B degradation than the single BiPO4 and Bi2WO6. The best photocatalytic activity of Bi2WO6-BiPO4 with nearly 100% Rh B degradation located at molar ratio of 1:1 after 20 min irradiation. The enhanced photocatalytic performance could be mainly ascribed to the formation of heteroj unction interface in Bi2WO6-BiPO4 which facilitated the transfer and separation of photogenerated electronhole pairs, as well as the strong visible light absorption originating from the sensitization role of Bi2WO6 to BiPO4. It was also found that the photodegradation of Rh B molecules was mainly attributed to the oxidation action of the generated O2.— radicals and partly to the action of hvb+ via direct hole oxidation process.