Synergistic effect of surface defect and interface heterostructure on TiO2/BiOIO3 photocatalytic oxide gas-phase mercury

Enhancing the photocatalytic activity of the semiconductors by introducing surface defect or forming interface heterostructure has attracted widespread interests. In this work, a novel photocatalysts, defect TiO2/BiOIO3 heterostructure possessing both surface defect and interface heterostructure, was prepared via calcination method for the first time. The physicochemical property of the as-prepared defect TiO2/BiOIO3 heterostructure was investigated by XRD, SEM, TEM, EDS, XPS, FT-IR, BET, DRS, and PL characterization. The results indicated that introducing surface defect and forming interface heterostructure on photocatalysts at the same time can enhance the visible light response, promote the transfer velocity of the photocarriers and suppress the recombination of photo-generated electron-hole pairs. Furthermore, it exhibits an enhanced activity on photocatalytic oxidation of gas-phase elemental mercury (Hg degrees), which shows the highest Hg degrees oxidation efficiency of 91.12% under visible light.