Synergistic photocatalysis for bacteria inactivation and organic pollutant removal by S-scheme heterojunction InVO/BiOI: Performance evaluation and mechanism investigation.

The low efficiency of charge carrier separation is a major limitation hindering the application of photocatalytic technology. Constructing S-scheme heterojunction photocatalysts not only effectively promotes the separation of charge carriers, but also maximizes the oxidative and reductive capabilities of the two monomers. In this study S-scheme heterogeneous InVO/BiOI photocatalyst was synthesized by hydrothermal method combined with calcination. The optimal sample 20 % InVO/BiOI can completely deactivate Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in 30 min, remove 20 mg/L TC 76.0 % in 60 min and 20 mg/L BPA 93.0 % in 90 min. Intermediate products of TC and BPA degradation were detected using LC-MS, and possible degradation pathways were proposed. The photocurrent and electrochemical impedance spectroscopy (EIS) tests confirm that InVO/BiOI exhibits excellent photocurrent intensity and photocarrier migration ability, which are crucial reasons for the enhancement of the photocatalytic performance of the InVO/BiOI composite. Capture experiments indicate that OH, O, h and eare reactive species. EPR further confirms the generation of OH and O. Combined with Kelvin probe force microscopy (KPFM) and band structure analysis, it is proposed that InVO/BiOI has an S-scheme charge transfer mechanism.