Novel mesoporous polyoxometalate hybrid catalysts for heterogeneous oxidation of thioethers

K6P2W18O62 and K14[NaP5W30O110] polyoxometalate salts are synthesized and immobilized within MCM-48, SBA-3, SBA-15 and NH3+ functionalized mesoporous silicas. The newly designed hybrid materials are studied as catalysts for oxidation of thioethers. Preyssler complex is found to be a more active catalyst compared to its Dawson analog. Texture and chemical composition of the silica framework is shown to have indispensable effect on oxidation efficiency, stability, and reusability of catalysts. Catalysts with larger pores are proved to be more proper for the oxidation of relatively large thioethers and functionalization improves catalyst's properties.

Figure optionsDownload as PowerPoint slideResearch highlights
► Synthesis of K6P2W18O62 and K14[NaP5W30O110] polyoxometalate (POM) salts.
► Synthesis of SBA-3, MCM-48, SBA-15 and NH3+ functionalized SBA-15 supports.
► Designation of hybrid catalysts by grafting POMs within the mesoporous supports.
► Newly designed heterogeneous catalysts are used for green oxidation of thioethers.
► Support's characteristics and W composition of POM affect the catalytic activity.