Oxygen vacancy enhanced photocatalytic performance towards marine microorganisms inactivation over Ag/Bi2O3

In this study, Bi2O3-OV with different concentrations of oxygen vacancies was prepared by reduction method, Ag NPs were loaded onto pure Bi2O3 and Bi2O3-OV by photodeposition. The effect of different electronic structures of the carrier on the performance and reaction mechanism of the Ag-loaded catalysts was also emphasized. The results showed that the sterilization rate of pure Bi2O3 was only 49.56% after half an hour of light exposure, the sterilization rate of Ag/ Bi2O3 composite catalyst without vacancies was as high as 76.17%, and the sterilization efficiency of Ag/ Bi2O3 composite catalyst with oxygen vacancies was up to 98.21%. The presence of vacancies caused the Ag/ Bi2O3 composite catalyst to produce 15.13 mu M H2O2, which was nearly twice as much as that of Bi2O3/0.5Ag, and was the main active species for sterilization, while the main active species for sterilization of the Ag/ Bi2O3 composite catalyst without vacancies was the hydroxyl radicals generated from the valence band. This work not only enriches the study of the mechanism of inactivation of marine microorganisms by silver-loaded photocatalysts, but also provides a theoretical basis for the advancement of marine pollution treatment technology.