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

• Published in: Advanced functional materials Vol. 33; no. 51
• Main Authors: Li, Xiu‐Fen, Wu, Pengfei, Kan, Liang, Niu, Qian, Sun, Sheng‐Nan, Huang, Qing, Lan, Ya‐Qian
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01-12-2023
• Subjects: Benzoic acid; Catalysts; Clusters; Hydrogen peroxide; Materials science; Metal-organic frameworks; methyl phenyl sulfone; Oxidation; photocatalytic oxidation of methyl phenyl sulfide; Selectivity; single‐metal sites; Structural design; Th6 clusters; Thorium
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202308534

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.
Twelve metal‐organic frameworks (MOFs) are assembled by Th6 cluster and metal complex units and are applied to study active site, product selectivity, and interaction between monometallic site and cluster in the photocatalytic oxidation of methyl phenyl sulfide (MPS). It is noted that Ni─PBA (4‐pyridin‐4‐yl benzoic acid)─Th6 exhibits the highest conversion rate (>99%) and methyl phenyl sulfone (MPSO2) selectivity (>97%).