Modulating Ce 6 Nodes of Ce-MOFs for Boosting the Photocatalytic Decarboxylative Oxygenation of Carboxylic Acids

Tuning the microenvironments of metal nodes in metal–organic frameworks (MOFs) is crucial for optimizing their photocatalytic performance, but it remains challenging. Herein, we report a benzoic acid (BA) modulator-assisted strategy to regulate the coordination microenvironment of Ce 6 nodes in Ce-based MOFs (Ce-1,3,5-benzenetribenzoate, Ce-BTB), thereby enhancing their photocatalytic activity toward the decarboxylative oxygenation of carboxylic acids. By variation of the BA amount, a series of Ce-BTB nanosheets with controlled crystallinity, morphology, and coordination microenvironment were obtained. The optimized Ce-BTB-60 exhibits superior visible-light-driven (425 nm) performance for converting arylacetic acids to aldehydes under O 2 atomosphere, attributed to promoted ligand-to-metal charge transfer (LMCT), suppressed charge recombination, and improved interfacial charge transport. Detailed radical trapping experiments and density functional theory (DFT) calculations reveal that the coordinated BA and mixed-valence Ce centers facilitate substrate binding and LMCT-driven radical generation. This work highlights coordination microenvironmental modulation as an effective strategy for designing MOF-based photocatalysts for organic transformations.