Underneath mechanisms into the super effective degradation of PFOA by BiOF nanosheets with tunable oxygen vacancies on exposed (101) facets

Construction of surface defects or/and exposed reactive facets is a promising strategy to improve the performance of photocatalysts . In this study, BiOF photocatalysts with tunable oxygen vacancies on the exposed (101) facets were successfully prepared by adjusting the concentration of ethylene glycol (EG). The prepared product with 50 % EG in the solution displayed remarkable photocatalytic activity for the recalcitrant pollutant perfluorooctanoic acid (PFOA), which could be completely decomposed within 6 h. The appropriate concentration of oxygen vacancy and the exposed (101) facets synergistically promoted the electron transfer from the defective surface to O 2 . Moreover, the oxygen vacancy introduced an intermediate band, which narrowed the bandgap and lowered the energy required for electron transition. DFT calculations and LC-MS-MS results revealed the principal-attack-sites of various active substances and figure out the entire PFOA degradation pathways. These profound findings are instrumental for a comprehensive understanding of the degradation process of PFOA in photocatalytic systems.