Meso‐ and Microporous Metal–Organic Frameworks for Efficient Photo‐Oxidation of Benzylamine

The construction of metal–organic frameworks (MOFs) with desirable structures for high‐performance photocatalysis is attractive but remains challenging. Here, a hierarchically meso‐ and microporous sc Cu‐MOF‐74 was synthesized in supercritical CO 2 ( sc CO 2 )/methanol solution. Compared with the conventional microporous Cu‐MOF‐74, the meso‐ and microporous sc Cu‐MOF‐74 has more exposed and accessible Lewis acid sites derived from the missing‐linker defects. The unique structure endows sc Cu‐MOF‐74 with superior molecular accessibility, enhanced separation, and transfer efficiency of photogenerated charges. High catalytic activity and reusability can be achieved in photo‐oxidative coupling of amines, reaching a maximum N‐benzylbenzaldimine yield rate of 4.80 mmol g −1 h −1 under mild conditions, that is, air atmosphere and room temperature. This study provides a new idea for improving the intrinsic photocatalytic activities of MOFs.