In this study, the confined Pt/Ce-MOF were for the first time synthesized using an in-situ vacuum self-assembly strategy. It is confirmed that the meso-Pt/CeO₂ catalyst derived from the confined Pt/Ce-MOF has excellent activity and stability in the catalytic oxidation of toluene, which is mainly due to the effective anchoring of Pt nanoparticles in Ce-MOF, and the interface effect between Pt nanoparticles and CeO₂. More importantly, it is discovered that the double-layer confinement effect of ordered mesoporous SBA-15 and Ce-MOF can effectively avoid the migration and aggregation of Pt nanoparticles, making meso-Pt/CeO₂ catalysts exhibit higher Pt dispersion. The structure-activity relationship and reaction mechanism of the meso-Pt/CeO₂ catalyst were explored by in situ surface-enhanced Raman spectroscopy (SERS) and in situ DRIFTs spectra. The results show that oxygen molecules in the air are firstly adsorbed to the surface of the catalyst, and then are activated as Ce-O and Pt-O active species during the reaction process. The benzyl alcohol, benzoic acid, benzoate and maleic anhydride are the main intermediate products, indicating that the reaction pathway may be as follows: adsorption of toluene → benzyl alcohol → benzoic acid → benzoate → maleic anhydride → … → carbon dioxide and water. Simultaneously, it is verified that the benzyl alcohol (C₆H₅CH₂O) and carboxylic acid species is the decisive step in the oxidation of toluene on basis of in situ SERS and DRIFTs spectra.

在这项研究中，首次使用原位真空自组装策略合成了受限的 Pt/Ce-MOF。证实了由受限Pt/Ce-MOF衍生的meso-Pt/CeO ₂催化剂在甲苯催化氧化中具有优异的活性和稳定性，这主要是由于Pt纳米粒子在Ce-MOF中的有效锚定，以及Pt纳米粒子与CeO ₂的界面效应。更重要的是，发现有序介孔SBA-15和Ce-MOF的双层限制效应可以有效避免Pt纳米粒子的迁移和聚集，使meso-Pt/CeO ₂催化剂表现出更高的Pt分散性。_{介观-Pt/CeO 2}的构效关系及反应机理通过原位表面增强拉曼光谱（SERS）和原位漂移光谱对催化剂进行了探索。结果表明，空气中的氧分子首先被吸附到催化剂表面，然后在反应过程中被活化为Ce-O和Pt-O活性物种。苯甲醇、苯甲酸、苯甲酸和马来酸酐是主要的中间产物，表明反应途径可能为：甲苯吸附→苯甲醇→苯甲酸→苯甲酸→马来酸酐→……→二氧化碳和水。同时，验证了苯甲醇（C ₆ H ₅ CH ₂ O) 和羧酸物质是甲苯氧化的决定性步骤，基于原位 SERS 和 DRIFTs 光谱。