Titanium oxide/highly dispersed silica

Highly dispersed titanium oxide species on silica prepared by the sol-gel method catalyse the selective epoxidation of propene by molecular oxygen.59 This is potentially very significant as the new commercial route to propene oxide is based on the reaction of propene with hydrogen peroxide catalysed by a mixed Ti-Si oxide the direct reaction with oxygen has clear advantages. 

Isolated highly dispersed titanium oxide species on silica as photocatal5dic active sites for non-oxidative direct methane coupling, were successfiilly prepared by sol-gel method, in which hydrolysis of TEOS to form Si(OH)4 would be completed, followed by condensation to form Si-O-Ti bonds. It was found that both hydrolysis and condensation time much affected the formation of the isolated highly dispersed species. The sample prepared by the present sol-gel method showed higher activity than those prepared by conventional impregnation method. 

Preparation of isolated highly dispersed titanium oxides on silica by sol-gel method for photocatalytic non-oxidative direct methane coupling... 

A new design of photocatalyst, double loading of ceriiun and titaniiun oxides on silica, was examined for the non-oxidative direct methane coupling. In the present method, both highly dispersed cerium and titanium oxide species coexisting on silica were obtained. This provided totally larger number of photoactive sites than that for the system of single metal oxide on silica. 

Preparation of highly dispersed titanium and cerium oxides on silica... 

The tailored design of the titanium-coordinated surfactant and its application in an evaporation-induced self-assembly process followed by heat treatment enabled the preparation of periodic mesoporous silica-based films with a high loading and good dispersion of tetrahedral titanium atoms within the silica matrix. This approach is also feasible for a variety of other transition metal oxides. 

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