Atomically precise gold nanoclusters have received increasing attention in photocatalysis but suffered from self-oxidation coalescence induced by photo-generated holes. Herein, we report an efficient charge engineering strategy to improve the photo-oxidation activity and stability of Au₂₅(PPh₃)₁₀(SC₃H₆Si(OC₂H₅)₃)₅Cl₂ nanocluster (AuNC) taking advantage of Z-scheme AuNC/ultrathin BiOCl nanosheets (2D-BiOCl) heterojunction for visible light oxidative self-coupling of amines. The turnover frequency (TOF) over AuNC/2D-BiOCl for benzylamine can reach 1916 h^―1, much higher than that of most previously reported gold catalysts with a TOF usually less than 500 h^―1. Moreover, the heterojunction can be stabilized for six cycles with the intact structure of AuNC remained. The enhanced photocatalytic activity of AuNC/2D-BiOCl was predominantly attributed to the formation of Z-scheme heterojunction, which effectively accelerated the transfer and separation of photo-generated carriers. Especially, the consumption of holes in AuNC by injected electrons from 2D-BiOCl can inhibit the self-oxidation of AuNC, thus improve its stability. This study provides some insights into the design of metal nanocluster catalysts with Z-scheme charge transfer for the application of photocatalysis.

原子精确的金纳米簇在光催化中受到越来越多的关注，但遭受了光生空穴诱导的自氧化聚结的困扰。本文中，我们报告了一种有效的电荷工程策略，可利用以下优点来提高Au ₂₅（PPh ₃）₁₀（SC ₃ H ₆ Si（OC ₂ H ₅）₃）₅ Cl ₂纳米簇（AuNC）的光氧化活性和稳定性。用于胺的可见光氧化自偶联的Z方案AuNC /超铀BiOCl纳米片（2D-BiOCl）异质结。AuNC / 2D-BiOCl在苄胺上的周转频率（TOF）可以达到1916 h ^-1，远远高于大多数以前报道的TOF通常少于500 h ^-1的金催化剂。此外，在保留AuNC完整结构的情况下，异质结可以稳定六个周期。AuNC / 2D-BiOCl的增强的光催化活性主要归因于Z型异质结的形成，这有效地促进了光生载流子的转移和分离。特别是，来自2D-BiOCl的注入电子消耗了AuNC中的空穴，可以抑制AuNC的自氧化，从而提高其稳定性。这项研究为Z方案电荷转移的金属纳米簇催化剂在光催化应用中的设计提供了一些见识。