Functional Macro-Microporous Metal-Organic Frameworks for Improving the Catalytic Performance

Constructing hierarchical pore structures in metal-organic frameworks (H-MOFs) can significantly enhance their catalytic performance. However, common strategies for preparing H-MOFs only focus on creating hierarchical pores to facilitate the molecular diffusion but neglect the synergistic effect of hierarchical pores with multiactive sites in H-MOFs. Therefore, the development of a suitable strategy with hierarchical pores and multiactive sites in H-MOFs serving as multifunctional and efficient catalysts is highly desired. In this work, a facile strategy is developed to prepare functional nanoparticles (NPs)/MOFs catalysts with a macro-microporous structure (NPs/M-MOFs) and multiactive sites (more NPs and base sites) through template etching and immersion reduction. The as-prepared Pt/M-zeolitic imidazolate framework-8 (ZIF-8) shows high performance in the Knoevenagel condensation-hydrogenation two-steps catalytic reaction, mainly due to the existence of macropores in the ZIF-8 and the exposure of the multiactive sites (more Pt NPs and base sites). This strategy is potentially extendable to other series of MOFs for structuring functional NPs/M-MOFs catalysts that can optimize the performance of catalytic reaction.