Hierarchically Porous Single Nanocrystals of Bimetallic Metal–Organic Framework for Nanoreactors with Enhanced Conversion

Nanoreactors constructed by encapsulation of catalytic species in hierarchically porous metal–organic framework (HPMOF) nanostructures have emerged as a type of promising catalysts that deliver enhanced conversion and excellent selectivity/stability. However, the controlled synthesis of small HPMOF nanocrystals with tunable size and nanostructures remains challenging. Here, by coupling external ultrasonication with the inherent binding competitions between the metal ions of bimetallic Co/Zn-ZIF, we design and develop a new strategy, dynamic growth, for the facile synthesis of small (down to ca. 95 nm), single-crystalline and structure-/size-tunable HPMOF nanocrystals through a one-pot, additive-free procedure. Benefiting from the combined structure/size regulation, nanoreactors based on our small nanocrystals of meso-HP-Co/Zn-ZIF-50% are able to deliver exceptional conversion while keeping their excellent selectivity and stability. Insights gained from this work opens a new avenue for the development of complex/dynamic coordination materials in which the compositions, structures, properties, and functions can be designed/tuned through the coupling of their inherent binding competitions with external stimuli.