Steering the Assembly and Disassembly of Active Pd Sites in Organometallic Networks for Electrocatalytic Performance and Organic Transformation

摘要

Hierarchical bottom-up structuring in nature provides inspiration for the construction of self-assembled complex with advanced properties out of simple building blocks. However, the development of self-standing assemblies of ultrasmall metal nanoparticles using redox ligands is still challenging. Here, a molecule-confined reduction strategy to prepare robust self-organized superstructures through metal-ligand interfacial interactions and hydrogen bonding is reported. High-density and well-separated Pd nanoparticles and single atoms are embedded within organometallic matrixes (Pd@eFc) via in situ reduction of the Pd precursor by redox-active ligands. Furthermore, these metal-organic networks can be disassembled into fragments with highly dispersed Pd nanoparticles and single atoms by solvent mediation. Strikingly, Pd@eFc disassembly delivers excellent oxygen reduction performance, while its assembly can act as a selective hydrogenation catalyst. This viable molecule-confined reduction strategy can also be applied to other organometallic superstructures (e.g., Au@eFc, Ag@eFc). The findings thus encourage on-going study to explore controlled hierarchically self-assembled superstructures for a wide range of catalysis.