Facile One‐Pot Synthesis of ZnO/SnO₂ Heterojunction Photocatalysts with Excellent Photocatalytic Activity and Photostability

Abstract

Abstract A series of porous ZnO/SnO 2 heterojunction photocatalysts with different Sn contents were successfully synthesized through a simple one‐pot solvothermal method. The evolution of particle size, composition, texture structure, and photocatalytic performance as a function of Sn content was systematically studied. It is found that the as‐synthesized ZnO/SnO 2 heterojunction photocatalysts show much higher photocatalytic activity than ZnO, SnO 2 , Sn x Zn 1− x O 2 , and ZnO/Zn 2 SnO 4 . Photocorrosion of ZnO was observed, for all samples that contain ZnO nanocrystals, during the photocatalytic process. The photostability of ZnO/SnO 2 samples containing small ZnO nanoparticles were significantly enhanced. The most photostable ZnO/SnO 2 sample exhibits at least 6.5 times higher photostability than pure ZnO sample. It is proposed that the photocatalytic activities and photostability of the ZnO/SnO 2 photocatalysts are determined by the photogenerated carrier transport rates at the SnO 2 –ZnO and ZnO–electrolyte interfaces.