Z-scheme Ag2MoO4/BiVO4 photocatalyst using Ag as charge transfer mediator: Performance optimization and Microcystis aeruginosa inactivation application

Abstract

Eutrophication in water bodies has caused harmful algal blooms (HABs) to occur worldwide, resulting in significant impacts on both the environment and human well-being. In this work, a Z-scheme Ag2MoO4/BiVO4 (AMB) photocatalyst with Ag as the charge transfer mediator was constructed by depositing Ag2MoO4 on BiVO4 through a simple in-situ generation method and characterized by various techniques. In addition, AMB-30% has the best photocatalytic performance, removing 99% of chlorophyll a within 3 h and performing well under different conditions. The physiological characteristics of algal cells were also investigated. The results showed that AMB-30% could not only destabilize the stability, membrane permeability and physiological function of algal cells, but also degrade the intracellular organic matter leaked out from the algal cells, effectively avoiding the secondary pollution of the water body while inactivating algae. Based on the identification of the active substance, the possible algal removal mechanism of Ag2MoO4/BiVO4 under the photocatalytic system was further proposed. Finally, the results of the five-cycle experiments and XRD characterization of AMB-30% demonstrated that it has great recyclability and stability, thus offering a favorable prospect in mitigating HABs.