Reducing the Au particle size and increasing the number of defective Ti⁴⁺ species have been considered effective strategies to boost the catalytic performance of Au–Ti bifunctional catalysts used for propylene epoxidation utilizing H₂ and O₂. Consequently, the development of an effective method that can simultaneously achieve these goals is of significant scientific and industrial importance. Herein, we demonstrate, for the first time, that the simultaneous immobilization of small Au particles (approximately 1.6 nm) onto uncalcined titanium silicate-1 (i.e., TS-1-B) and facilitation of the formation of defective Ti⁴⁺ species can be achieved using a modified deposition–precipitation (DP) method utilizing ammonia solution as the precipitant. The as-synthesized catalyst exhibits a significantly enhanced propylene oxide (PO) formation rate combined with fascinating PO selectivity and hydrogen efficiency, which were better than the reference catalyst prepared via the DP urea (DPU) method and other reported Au/uncalcined TS-1 catalysts. The catalyst structure–performance relationship was established using multiple characterization studies. the ammonia treatment facilitates the hydrolysis of some of the ≡Ti-O-Si≡ bonds into defective Ti⁴⁺ species (i.e., Ti(OSi)₃OH), which not only provides more active Ti⁴⁺ sites but also favors the uniform deposition of Au. This methodology and the insights stated herein may also be applicable for enhancing the dispersion of Au in a variety of zeolite-supported catalysts.

减小 Au 粒径和增加有缺陷的 Ti ^{4+物种的数量已被认为是提高用于利用 H} ₂和 O ₂进行丙烯环氧化的 Au-Ti 双功能催化剂催化性能的有效策略。因此，开发一种可以同时实现这些目标的有效方法具有重要的科学和工业意义。在此，我们首次证明将小 Au 颗粒（约 1.6 nm）同时固定到未煅烧的硅酸钛-1（即 TS-1-B）上并促进有缺陷的 Ti ^4+的形成使用氨溶液作为沉淀剂的改进沉积-沉淀 (DP) 方法可以实现物种。合成后的催化剂表现出显着提高的环氧丙烷 (PO) 形成速率以及迷人的 PO 选择性和氢气效率，优于通过 DP 尿素 (DPU) 方法和其他报道的 Au/未煅烧 TS-1 制备的参考催化剂催化剂。使用多项表征研究建立了催化剂结构-性能关系。氨处理促进了一些 ≡Ti-O-Si ≡ 键水解成有缺陷的 Ti ⁴⁺物质（即 Ti(OSi) ₃ OH），这不仅提供了更活跃的 Ti ⁴⁺站点，但也有利于 Au 的均匀沉积。这种方法和本文所述的见解也可适用于增强 Au 在各种沸石负载催化剂中的分散。