LAUSR

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.