Ordered mesoporous Sn-TiO2 catalysts via an evaporation induced self-assembly method for the Baeyer-Villiger oxidation of cyclohexanone by molecular oxygen

In order to improve the catalytic performance in the Baeyer-Villiger oxidation of cyclohexanone by molecular oxygen, ordered mesoporous Sn-TiO2 catalysts with high Lewis acidity were successfully designed and synthesized via a facile one-pot evaporation induced self-assembly method. Their physical and chemical properties were characterized by different techniques including XRD, N-2 adsorption-desorption, UV-Vis spectra, ICP, Py-IR, SEM and TEM. The XRD, TEM and N-2 adsorption-desorption results showed that the ordered mesoporous structure can be preserved after tin incorporation. The UV-Vis, SEM and Py-IR results indicated that tin species can be homogeneously tetrahedrally incorporated in the crystalline framework of mesoporous anatase TiO2 and create the Lewis acidity. The ordered mesoporous 15Sn-TiO2 catalyst showed highest catalytic performance where cyclohexanone conversion of 91.4 % and e-caprolactone selectivity of 93.2 %. Moreover, catalytic recycling tests demonstrated that the Sn-TiO2 catalysts exhibited high potential reusability.