Synergistic modulation of BiOI by atomic-level vacancies and dominant facets for efficient photocatalytic degradation of bisphenol A†

Precise control of desirable facets and vacancies is expected to be a promising strategy for improving the photocatalytic performance of catalysts. Herein, BiOI-1 and BiOI-2 were designed and prepared with (102) and (110) as the dominant exposed facets, respectively. Moreover, BiOI-1 and BiOI-2 correspond to the major types V_BiIBi and V_BiOBiBi, respectively. The experimental results showed that the degradation and mineralization of bisphenol A (BPA) by BiOI-2 could reach 100% and 95.90% under visible light irradiation. The excellent catalytic performance of BiOI-2 is attributed to the optimization of the energy band structure by its special facets and vacancies, and the narrow band gap promotes the separation of photogenerated electron–hole pairs. Meanwhile, the strong reducing property of the conduction band (CB) and the strong adsorption capacity for water and oxygen contribute to the fact that BiOI-2 can generate a large amount of reactive oxygen species (ROS). This work provides an atomic-scale understanding of the synergistic effects of vacancies and facets on catalysts and offers new directions in the management of water environmental pollution.