Directional Engraving within Single Crystalline Metal–Organic Framework Particles via Oxidative Linker Cleaving

An oxidative linker cleaving (OLC) process was developed for surgical manipulation of the engraving process within single crystalline MOFs particles. The strategy relies on selective degradation of 2,5-dihydroxyterephthalic acid linker into small molecular fragments by oxidative ring-opening reactions, resulting in controllable scissoring of framework. By regulation of the generation and diffusion of oxidative species, the core MOFs will undergo divergent etching routes, producing a series of single crystalline hollow and yolk–shell MOF structures. In addition, the OLC process can be initiated and localized around the pre-embedded Pd NPs through on-site catalytic generation of oxidative species, leading to solitary confinement of multiple NPs within one single crystalline MOF particle, namely, a multi-yolk–shell structure. This unique architecture can effectively protect NPs from agglomeration while realizing size selective catalysis at the same time.