Limited light absorption and severe charge recombination have been widely acknowledged as the two main obstacles restricting the application of P25 in NO photocatalytic conversion. In this work, an advanced heterojunction photocatalyst of Bi/BiOI/black TiO₂ was synthesized via an in-situ solid-state chemical reduction method. The black TiO₂ extended the light absorption to the full spectral region. It constructed a direct Z-scheme heterojunction with BiOI nanosheets, not only promoting the charge separation, but also preserving the strong oxidation ability of photogenerated holes in black TiO₂ and strong reducing ability of photogenerated electrons in BiOI. Thus, more •O₂^- and •OH radical could form when Bi/BiOI/black TiO₂ was subjected to visible light irradiation. Besides, the introduced Bi metal nanoparticles could also enhance the light utilization and served as a cocatalyst to accept the electrons. Therefore, enhanced NO photocatalytic oxidation activity was obtained, with the optimal sample Bi/BiOI/black TiO₂ exhibiting a high NO conversion efficiency of ∼70% and NO_x removal of ∼45%. This work may provide a refreshing perspective for the design of heterojunction photocatalysts for efficient NO photocatalytic purification and other photocatalytic applications.

有限的光吸收和严重的电荷复合已被广泛认为是限制 P25 在 NO 光催化转化中应用的两个主要障碍。在这项工作中，通过原位固态化学还原方法合成了一种先进的 Bi/BiOI/黑色 TiO ₂异质结光催化剂。黑色TiO ₂将光吸收扩展到整个光谱区域。它与BiOI纳米片构建了直接Z型异质结，不仅促进了电荷分离，而且保留了黑色TiO ₂中光生空穴的强氧化能力和BiOI中光生电子的强还原能力。因此，更多的•O ₂ ^-可见光照射Bi/BiOI/黑色TiO ₂可形成•OH自由基。此外，引入的铋金属纳米粒子还可以提高光利用率，并作为接受电子的助催化剂。因此，获得了增强的NO光催化氧化活性，最佳样品Bi/BiOI/黑色TiO ₂表现出~70%的高NO转化效率和~ 45%的NO _x去除率。这项工作可能为设计用于高效 NO 光催化净化和其他光催化应用的异质结光催化剂提供新的视角。