With the aid of the confined conversion of layered silicate RUB-15, homogeneously dispersed Au and SnO₂ nanoparticles (NPs) were generated in the confined layer space of RUB-15. The Au–SnO₂/SiO₂ composite was obtained with the structure that ultrafine Au and SnO₂ NPs were supported on SiO₂ lamellas. Benefited by the Sn(II)-assisted in situ reduction strategy, Au NPs were highly uniformed and evenly distributed in/on the RUB-15. This Au–SnO₂/SiO₂ composite was employed as a catalyst to the reduction of 4-nitrophenol showing excellent catalytic activity. The catalytic rate constant at room temperature was calculated to be 6.64 min^–1, which was dramatically higher than that of Au/SiO₂ composite produced by reduction with hydrazine hydrate on the same support of layered silicate RUB-15. The interaction between Au and SnO₂ NPs increased the electron density around Au NPs, which was demonstrated to be an essential factor to the excellent catalytic activity of the Au–SnO₂/SiO₂ composite. The simple and universal synthesis method afforded precise control over the size/spatial arrangement of Au and SnO₂ NPs on SiO₂ lamellas. The high activity of the Au–SnO₂/SiO₂ composite demonstrated that the strategy used in this study has good potential application prospect. Furthermore, this work provided new perspective on the catalysis mechanism to the metal/semiconductor synergistic catalyst system.

中文翻译：

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均匀分散的层状硅酸盐中均相分散的Au和SnO ₂纳米粒子的受限生成

借助于层状硅酸盐RUB-15的密闭转化，在RUB-15的密闭层空间中产生了均匀分散的Au和SnO ₂纳米颗粒（NP）。得到了Au-SnO ₂ / SiO ₂复合材料，其结构是将超细的Au和SnO ₂ NPs负载在SiO ₂薄片上。受益于Sn（II）辅助的原位还原策略，Au NP高度均匀且均匀分布在RUB-15中。这种Au-SnO ₂ / SiO ₂复合材料被用作还原4-硝基苯酚的催化剂，显示出优异的催化活性。室温下的催化速率常数经计算为6.64 min ^–1，比在层状硅酸盐RUB-15的相同载体上用水合肼还原制得的Au / SiO ₂复合材料要高得多。Au和SnO ₂ NPs之间的相互作用增加了Au NPs周围的电子密度，这被证明是Au-SnO ₂ / SiO ₂复合材料优异的催化活性的重要因素。简单通用的合成方法可精确控制SiO ₂薄片上Au和SnO ₂ NP的尺寸/空间排列。Au–SnO ₂ / SiO ₂的高活性综合证明该研究中使用的策略具有良好的潜在应用前景。此外，这项工作为金属/半导体协同催化剂体系的催化机理提供了新的视角。