Characterization and Photocatalytic Properties of Titanium-Containing Mesoporous SBA-15

Titanium-containing mesoporous SBA-15 (Ti-SBA-15) with various titanium contents were synthesized and characterized by means of N2 adsorption, inductively coupled plasma-atomic emission spectroscopy, X-ray diffraction, UV-Vis diffusion reflectance spectroscopy, X-ray photoelectron spectroscopy, 29Si magic-angle spinning nuclear magnetic resonance, and transmission electron microscopy in combination with energy-dispersive X-ray analysis techniques. The materials were also examined in terms of photocatalytic properties of the photodecomposition of Orange II in liquid phase. It was observed that a limited content of titanium can be incorporated into the silicate framework of SBA-15 without provoking structure changes. Anatase phase was observed on the external surface of the solid particles at high titanium loadings. In addition, the particle size of TiO2 increased with increasing the titanium loading. Both TiO2 nanoparticles and the titanium ions in the framework of Ti-SBA-15 possess photoactivity and the highest activity was observed on the sample with a Ti/Si ratio of about 0.09.