Photoactive Heteropore Covalent Metal–Organic Frameworks for CO 2 Photoreduction

Metal–organic frameworks (MOFs) as a class of promising photocatalysts have been used for photocatalytic CO 2 reduction reaction (CO 2 RR). Although many strategies have been developed for enhancing the photocatalytic activities, constructing photoactive heteropore MOFs for CO 2 RR remains largely unexplored. Herein, we report the synthesis of two two-dimensional (2D) copper cyclic trinuclear unit (Cu-CTU)-based heteropore covalent MOFs (CMOFs) and two homopore analogues. Interestingly, the heteropore CMOFs showed two times higher CO 2 uptake than their homopore analogues. Moreover, the introduction of photosensitive units into heteropore CMOFs promoted light harvesting as well as charge separation, achieving a CO generation rate of 3548 μmol g –1 h –1 with 94.7% selectivity and an apparent quantum yield (AQY) of 6.78% at 420 nm in the presence of [Ru(bpy) 3 ]Cl 2 . Notably, the photoactive heteropore CMOFs delivered high photocatalytic activity under diluted CO 2 and natural sunlight conditions. Our work demonstrated that incorporation of heteropore structures and photosensitive units into MOFs can synergistically enhance photocatalytic CO 2 RR performance.