BiOBr and AgBr co-modified ZnO photocatalyst: A novel nanocomposite with p-n-n heterojunctions for highly effective photocatalytic removal of organic contaminants

Abstract A series of ZnO/BiOBr/AgBr visible-light-induced photocatalysts were synthesized by a simple procedure. Among ternary nanocomposites, the ZnO/BiOBr/AgBr (30%) photocatalyst displayed the highest ability for photodegradation of MO, which was almost 95.3 and 3 times as high as the bare ZnO and binary ZnO/BiOBr (30%) nanocomposite, respectively. The promoted photocatalytic ability of the ZnO/BiOBr/AgBr (30%) photocatalyst was assigned to the improved absorption of visible light, rapid electron/hole separation, and boosted textural properties. It was proposed that construction of p-n-n heterojunctions between the counterparts could play pivotal role in separation of the charges. Furthermore, the O 2 − , OH , and h + species were detected as the oxidative species in the photocatalytic system by the scavenging tests. The present work benefited the improvement of photocatalytic performance of ZnO through integration with two small band gap semiconductors for water purification.