Developing a powerful bifunctional catalyst for tandem reactions is essential to the future carbon neutrality by reducing the energy consumption in chemical industries. Herein, mesoporous zeolite-encapsulated palladium (Pd) nanoparticles (Pd@meso-ZSM-5) synthesized via emulsification-demulsification followed by a dry-gel transformation method were demonstrated to have a remarkable catalytic performance for a one-pot multiple tandem reaction of cyclic ketones (cyclopentanone, cyclohexanone) to bicyclic alkanes (bicyclopentane, bicyclohexane). Compared with supported catalysts (Pd/meso-ZSM-5) and microporous zeolite-encapsulated catalysts (Pd@ZSM-5) with a primary product of monocyclic alkane (cyclopentane, cyclohexane), Pd@meso-ZSM-5 shows much higher catalytic efficiency for the bicyclic alkanes synthesis, which was previously unattainable in the conventional two-step synthesis route. Controlled experiments and detailed characterizations show that mesoporosity provides sufficient space for the generation and diffusion of large molecular intermediates, and the intimate acid-Pd interface promotes the conversion of intermediates. This work proposes a design strategy for a mesoporous zeolite-encapsulated metal catalyst, which efficiently provides cooperative acid-hydrogenation catalysis.

通过降低化学工业的能源消耗，开发用于串联反应的强大双功能催化剂对于未来的碳中和至关重要。在此，通过乳化-破乳然后干凝胶转化法合成的介孔沸石包封钯 (Pd) 纳米粒子 (Pd@meso-ZSM-5) 被证明对一锅多串联反应具有显着的催化性能环酮（环戊酮、环己酮）到双环烷烃（双环戊烷、双环己烷）。与主要产物为单环烷烃（环戊烷、环己烷）的负载型催化剂（Pd/meso-ZSM-5）和微孔沸石包封催化剂（Pd@ZSM-5）相比，Pd@meso-ZSM-5表现出更高的催化活性双环烷烃合成的效率，这是以前在传统的两步合成路线中无法实现的。受控实验和详细表征表明，介孔性为大分子中间体的生成和扩散提供了足够的空间，而紧密的酸-Pd 界面促进了中间体的转化。这项工作提出了一种中孔沸石包封金属催化剂的设计策略，可有效提供协同酸加氢催化作用。