Preparation of hydrophobically modified single-site Ti-containing mesoporous silica (TiSBA-15) and their enhanced catalytic performances

Hydrophobic modification of single-site Ti-oxide moieties containing mesoporous silica (TiSBA-15) surfaces was performed by using triethoxyfluorosilane (TEFS) as a silylation reagent. The pore structure as well as the high surface area of TiSBA-15 was retained even after modification of these surfaces. TiSBA-15 modified with suitable amount of TEFS exhibited higher catalytic performance for the selective oxidation of cyclooctene to 1,2-epoxy cyclooctane using aqueous H2O2 as an oxidant than the unmodified TiSBA-15. The improvement of surface hydrophilic–hydrophobic properties of TiSBA-15 is quite effective for the enhancement of catalytic activity.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (192 K)Download as PowerPoint slideHighlights► The post functionalization by TEFS enables to improve the surface hydrophilic–hydrophobic properties of TiSBA-15. ► The mesoporous structure of TiSBA-15 and local structure of single-site Ti-oxide moieties are retained even after surface modification. ► The grafting of suitable amount of TEFS onto TiSBA-15 is effective for enhancement of catalytic performances for the selective epoxidation of cyclooctene using aqueous H2O2.