In order to improve the efficiency of TiO2, material with large surface area such as mesoporous silica is usually used as a support. In this study, the TiO2 was dispersed on mesoporous silica, MCM-41 by an impregnation method, meanwhile the bulk TiO2 was prepared by sol gel method. The X-ray diffraction (XRD) patterns showed that the intensities of diffraction peaks for MCM-41 decreased with the increase of the TiO2 loading, suggesting that the higher loading amount of TiO2 might lead to less ordered structure of MCM-41. The successful addition of TiO2 on MCM-41 was also confirmed from the fluorescence spectra, which the emission intensities of TiO2 and MCM-41 increased and decreased, respectively, with the increase of TiO2 loading on the MCM-41. The activities were compared between the bulk and dispersed TiO2 for photocatalytic oxidation of hexanol. Both bulk and dispersed TiO2 on MCM-41 showed good photocatalytic activity, while the MCM-41 did not show photocatalytic activity. Since the efficiency of photocatalyst can be defined by its respective turnover number (TON), the comparison between bulk and dispersed TiO2 on MCM-41 was made based on their TON values. It was revealed that the dispersed TiO2 on the MCM-41 with 5 wt% of TiO2 loading was the most efficient photocatalyst among all the samples.
Photocatalytic reduction of carbon dioxide by strontium titanate nanocube-dispersed mesoporous silica
