Facile Synthesis of a Bi[sub.2]WO[sub.6]/BiO[sub.2−x] Heterojunction for Efficient Photocatalytic Degradation of Ciprofloxacin under Visible Light Irradiation

In this work, a Z-scheme Bi[sub.2]WO[sub.6]/BiO[sub.2−x] heterojunction was successfully prepared using a self-assembly strategy. Various characterization techniques demonstrated that the formation of the heterojunction not only accelerated the separation of photoinduced carriers but also weakened the recombination rate of photogenerated electron-hole pairs-. The Bi[sub.2]WO[sub.6]/BiO[sub.2−x] composites had a wider absorption edge than Bi[sub.2]WO[sub.6] in the range of 200-800 nm, which improved the photocatalytic performance of ciprofloxacin (CIP) degradation under xenon lamps. As a result, the Z-scheme heterojunction Bi[sub.2]WO[sub.6]/BiO[sub.2−x] composite exhibited excellent photocatalytic activity. Catalyzed by the optimal 20% Bi[sub.2]WO[sub.6]/BiO[sub.2−x] (0.5 g/L), the removal rate of CIP (10.0 mg/L) was 91.8% within 2 h irradiated by visible light, which was 2.37 times that of the BiO[sub.2−x] catalyst. This work will provide a fresh perspective on the construction of visible-driven Z-scheme photocatalysts for wastewater treatment.