Non-Noble-Metal POM@MOF for Enhancing the Visible Photoinduced Baeyer-Villiger Oxidation Reactions

Developing highly efficient, environmentally friendly, inexpensive, and readily available photocatalysts for Baeyer-Villiger (B-V) oxidation reactions is of significant importance. This study involved encapsulating Keggin-type H₃PMo₁₂O₄₀ and H₄SiW₁₂O₄₀ within a Cu-tr₂pr framework to synthesis two novel isomorphic POM@MOFs (CT-PMo and CT-SiW), which is the first time that polyoxometalates (POMs) have been added to metal-organic frameworks (MOFs) constructed with the participation of tr₂pr organic ligands. The modulation of photoelectrochemical properties and photocatalytic activity was achieved by regulating POMs. Photoelectrochemical testing revealed that CT-PMo exhibits stronger light absorption, faster charge transfer rates, lower resistance and reduced probability of recombination compared to CT-SiW. The photoinduced B-V oxidation reaction demonstrates that CT-PMo has higher catalytic activity, with a yield of 97.1% and turnover numbers and turnover frequencies of 971 and 923.0 h^-1, respectively. CT-PMo is the first noble metal-free catalyst for the photoinduced B-V oxidation reaction based on the Mukaiyama method, exhibiting the highest turnover frequencies value along with outstanding structural stability and recyclability, offering broad industrial application prospects.