A series of colored TiO₂/Bi₅O₇I composites were successfully fabricated. The physicochemical properties of the as-prepared TiO₂/Bi₅O₇I heterostructures were investigated by XRD, SEM, TEM, HRTEM, FT-IR, BET, UV–vis DRS, XPS and PL characterization. The characterization indicates that colored TiO₂ nanoparticles are tightly anchored to the Bi₅O₇I nanorods to form heterojunctions. The photocatalytic activity of the sample was examined by photocatalytic oxidation of gas-phase Hg⁰ under visible-light irradiation. The results show that TiO₂/Bi₅O₇I composites exhibits highly enhanced visible light photocatalytic activity compared to pure Bi₅O₇I. Hg⁰ removal rate of TiO₂/Bi₅O₇I composite is up to 89%. Compared with the pure Bi₅O₇I, the as-prepared composite photocatalyst enhanced the visible light absorption and increased the specific surface area. More importantly, the heterostructure formed in the composite effectively promotes the charge transfer, ultimately improves the photocatalytic activity. Meanwhile, the cyclic experiments were performed to confirm the stability of TiO₂/Bi₅O₇I composites. The influence of various flue gas components (O₂, NO and SO₂) on the performance of photocatalytic removal of Hg⁰ was studied. Based on characterization and experiments, the reasonable charge transfer and photocatalytic reaction mechanism were proposed.

成功制备了一系列有色TiO ₂ / Bi ₅ O ₇ I复合材料。通过XRD，SEM，TEM，HRTEM，FT-IR，BET，UV-vis DRS，XPS和PL表征研究了所制备的TiO ₂ / Bi ₅ O ₇ I异质结构的理化性质。该表征表明，着色的TiO ₂纳米颗粒紧密地锚定在Bi ₅ O ₇ I纳米棒上，形成异质结。通过在可见光照射下气相Hg ⁰的光催化氧化来检查样品的光催化活性。结果表明，TiO ₂ / Bi ₅与纯Bi ₅ O ₇ I相比，O ₇ I复合材料表现出更高的可见光光催化活性。TiO ₂ / Bi ₅ O ₇ I复合材料的Hg ⁰去除率高达89％。与纯Bi ₅ O ₇ I相比，所制备的复合光催化剂增强了可见光吸收并增加了比表面积。更重要的是，复合物中形成的异质结构有效地促进了电荷转移，最终提高了光催化活性。同时，进行循环实验以确认TiO ₂ / Bi ₅ O的稳定性。₇ I复合材料。研究了各种烟气成分（O ₂，NO和SO ₂）对光催化去除Hg ⁰的性能的影响。通过表征和实验，提出了合理的电荷转移和光催化反应机理。