Integrating Metal Complex Units and Redox Sites into Thorium‐Based Metal–Organic Frameworks for Selective Photocatalytic Oxidation of Sulfides.

A series of high‐symmetry Th6–metal‐organic frameworks (MOFs) are constructed using various metal complex units and the thorium (Th) cluster, and then being applied as a well‐defined catalyst model in the photocatalytic oxidation of methyl phenyl sulfide reactions. The integration of Th6‐MOFs by incorporating metal complex units and redox sites (Th6 cluster and single‐metal site) can effectively modulate the conversion rate and selectivity. Among them, Ni–PBA–Th6 (PBA = 4‐pyridin‐4‐yl benzoic acid) achieves up to ≈99% conversion and ≈97% selectivity for methyl phenyl sulfone. Experiments and theoretical calculations further elucidate that Th6 cluster is the catalytic site for the oxidation of methyl phenyl sulfide to methyl phenyl sulfone, while Ni–PBA is the catalytic site for the reduction of hydrogen peroxide. This work sheds new insight into the structural design and photocatalytic application of more efficient thorium‐based MOF catalysts. [ABSTRACT FROM AUTHOR]