Abstract A fully integrated X-ray photoelectron spectrometer (XPS) was employed for the investigation of the separation processes and recombination behaviors of photogenerated electrons and holes on the surface of AgCl and ultra-small nano-titanium oxide cluster composite photocatalyst (AgCl/TiO 2 ). A facile route, by direct colloidal synthesis, for preparing AgCl/TiO 2 with high stability and enhanced visible light (Vis) driven catalytic activity was reported. The photocatalytic activity of AgCl/TiO 2 , which revealed that the photo-degradation rate of the as-prepared AgCl/TiO 2 was nearly 10.5 times higher than that of bare AgCl, was evaluated by applying it to the photo-degradation of methyl orange (MO) in water solution. Moreover, AgCl/TiO 2 exhibited an outstanding long-term stability during ten cycles of photo-degradation. The band gap of AgCl decreased from 3.25 to 2.85 eV because of the ultra-small nano-TiO 2 clusters that were pinned to its surface. The results indicate that the band gap narrowing and surface plasmon resonance (SPR) of Ag (0) were two major contributors to the enhancement of the photocatalytic activity of AgCl/TiO 2 by improving the utilization of Vis. In situ XPS analysis was, therefore, certified as a beneficial method to explore the catalytic mechanism of photocatalysts. Graphic abstract

中文翻译：

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用完全集成的 X 射线光电子能谱仪研究 AgCl/TiO2 的光催化和光化学过程

摘要 采用全集成 X 射线光电子能谱仪 (XPS) 研究了 AgCl 和超小型纳米氧化钛簇复合光催化剂 (AgCl/TiO 2) 表面光生电子和空穴的分离过程和复合行为。 ）。报道了一种通过直接胶体合成制备具有高稳定性和增强的可见光 (Vis) 驱动催化活性的 AgCl/TiO 2 的简便途径。AgCl/TiO 2 的光催化活性表明，所制备的 AgCl/TiO 2 的光降解率比裸 AgCl 高近 10.5 倍，通过将其应用于甲基橙的光降解来评估(MO) 在水溶液中。此外，AgCl/TiO 2 在十次光降解循环中表现出出色的长期稳定性。由于固定在其表面的超小纳米 TiO 2 簇，AgCl 的带隙从 3.25 eV 降低到 2.85 eV。结果表明，Ag (0) 的带隙变窄和表面等离子体共振 (SPR) 是通过提高 Vis 利用率来增强 AgCl/TiO 2 光催化活性的两个主要因素。因此，原位 XPS 分析被证明是探索光催化剂催化机理的一种有益方法。图形摘要 因此，被证明是探索光催化剂催化机理的有益方法。图形摘要 因此，被证明是探索光催化剂催化机理的有益方法。图形摘要