Visible‐Light‐Responsive Polyoxometalate@Metal‐Organic Frameworks Involving Ir Metalloligands for Highly Selective Photocatalytic Oxidation of Sulfides to Sulfoxide
Jing Wang, Jing Wang, Yanan Liu, Zelong Yuan, Luoning Li, Pengtao Ma, Jingping Wang, Jingping Wang, Jingyang Niu
Abstract
Abstract The synthesis of highly efficient visible‐light‐responsive photocatalysts is fundamental to solving the problems of low efficiency and poor selectivity in photocatalytic organic synthesis reactions. We synthesized a crystalline polyoxometalate @metal‐organic framework material {Zn 4 (H 2 O) 8 [Ir(ppy) 2 (dcbpy)] 4 [SiW 12 O 40 ]} ⋅ 4H 2 O (Ir−SiW) by self‐assembly of Ir metalloligands with POMs. The introduction of Ir metalloligands extends the light absorbing range to visible light, improving the efficient utilization of solar energy. The transfer of photogenerated electrons from Ir metalloligands to SiW 12 was observed under visible light irradiation, which boosted the carrier separation efficiency. The synergistic effect of the two components increased the photocatalytic thioether oxidation activity, and the product methyl phenyl sulfoxide for 2.5 h under visible light irradiation (λ >400 nm) reached 99.5 %, which was higher than those of other POM‐based photocatalysts. Meanwhile, the yield of methyl phenyl sulfoxide was still higher than 97 % after three cycles, demonstrating the high stability and reusability of Ir−SiW.