TiO2 immobilized on 2D mordenite: effect of hydrolysis conditions on structural, textural, and optical characteristics of the nanocomposites.

Abstract

A series of novel TiO₂/2D mordenite nanocomposites were synthetized by the introduction of titanium tetraethoxide (TEOT) into the interlamellar space of 2D mordenite, its subsequent hydrolysis in water or a solution of 70% ethanol in water for 6, 12, and 24 h, and calcination. The resulting TiO₂/2D mordenite materials were studied by a set of complementary characterization techniques, including XRD, SEM-EDX, TGA, N₂ sorption, NMR, XPS and UV-vis spectrometry. It was observed that treatment in 70% ethanol solution preserves the ordered layered structure of 2D mordenite because TEOT hydrolysis is slowed down. This, in turn, leads to higher mesoporosity after calcination due to anatase nanoparticles of about 4 nm preventing the collapse of the interlamellar space. Immobilization of TiO₂ on the zeolite surface is evidenced by the formation of Si-O-Ti bonds. The bandgap width of the synthetized nanocomposites was found to be sensitive to the hydrolysis medium.