Pd@ZIF-67 Derived Recyclable Pd-Based Catalysts with Hierarchical Pores for High-Performance Heck Reaction

• Published in: ACS sustainable chemistry & engineering 2018-02, Vol.6 (2), p.2103-2111
• Main Authors: Zhou, Awu, Guo, Rui-Mei, Zhou, Jian, Dou, Yibo, Chen, Ya, Li, Jian-Rong
• Format: Article
• Language: English
• ISSN: 2168-0485; 2168-0485
• DOI: 10.1021/acssuschemeng.7b03525

Hierarchical-pore Pd@Co3O4, Pd@Co3O4/C, and Pd@Co/CNT (CNT = carbon nanotube) were fabricated via the one-step pyrolysis of palladium@zeolitic-imidazolate-framework-67 (Pd@ZIF-67); these catalysts employed as heterogeneous catalysts displayed excellent performance in the Heck reaction. These Pd@ZIF-67 derivatives retain the skeleton of the precursor and provide abundant exposed Pd active sites, and the pyrolysis treatment creates rich hierarchical pores affording a convenient path for reaction substrates accessing the active sites. As a result, they exhibit significantly enhanced yields (>99%) in the Heck reaction of iodobenzene with styrene, compared with that of Pd@ZIF-67 (78%). In addition, these catalysts can be easily recovered by magnetic separation and reused without losing activity. The Pd@Co/CNT was also used in catalyzing other Heck reactions, showing good performance. The work thus indicates a feasible method in the construction of hierarchical-pore catalysts from treating metal@MOF (metal–organic framework) composites for various organic reactions.