Oxygen vacancies self-modulating through phosphate to boost photocatalytic H2O2 generation

Oxygen vacancies (OVs) are widely used in photocatalytic H 2 O 2 generation for water remediation, and phosphate is a common ion in natural water. However, the potential mechanism regarding how phosphate influences the photocatalytic performance of OVs remains unclear. The role of phosphate in the photocatalytic H 2 O 2 generation by the OVs and subsequent contaminant degradation during OVs photocatalysis was investigated. Phosphates primarily formed complexes with Bi at OVs, altering the local electronic structure and O 2 adsorption pattern of this active site. This reduced the energy barrier for the formation of reactive oxygen species. The formation of complexes at OVs transforms H 2 O 2 generation pathway changed from two-step one-electron to one-step two-electron, thereby increasing H 2 O 2 generation. The H 2 O 2 product exhibited excellent in-situ pollutant treatment performance. This study provides valuable insights for optimizing environmental remediation strategies by exploring the effect of phosphate on the photocatalytic H 2 O 2 generation.