Enhanced Molecular Oxygen Activation on (001) Facets of Zn‐Doped BiOCl Nanosheets for Ciprofloxacin Degradation

Abstract The crucial oxidant in photocatalytic degradation of antibiotics is the photogenerated reactive oxygen species (ROS) but many photocatalytic processes suffer from low ROS generation efficiency. In this work, a Zn doping strategy is used to improve the photocatalytic oxygen activation ability of bismuth oxychloride (BiOCl) nanosheets with exposed (001) facets. Introduction of Zn into BiOCl can narrow the bandgap to extend photoresponse to visible region. Meanwhile, the separation of photoinduced charge carriers can also be promoted by increasing the valence band width of BiOCl. Furthermore, the adsorption and activation of oxygen molecules on the (001) surface are greatly enhanced by introducing more oxygen vacancies. Thus, the Zn‐BiOCl nanosheets have an excellent activity for the degradation of ciprofloxacin (CIP) under visible light by activating oxygen into superoxide radicals. The optimal ratio of Zn doping is 8% and the degradation rate is 2.6 times higher than that of BiOCl. The photocatalytic oxidation of CIP follows a pseudo‐first‐order kinetics. The removal efficiency of CIP reaches 98% in 80 min. Finally, the complete pathway of the CIP photocatalytic oxidation is unraveled by high performance liquid chromatography‐mass spectrometry. This study provides an advanced solution to promote the performance of photocatalyst to degrade organic pollutants in water.