High-temperature hydrothermal synthesis of crystalline mesoporous TiO_2 with superior photo catalytic activities

摘要

Mesoporous titanium dioxide with crystalline mesopore walls (M-TiO_2-ns) have been successfully synthesized through the self-assembly of poly 4-Vinylpyridine template and tetrabutyl titanate precursor based on their complex bond interaction under high temperature (180 ℃) hydrothermal conditions. X-ray diffraction shows that M-TiO_2-ns have highly crystalline mesopore walls with anatase phase characters; N_2 sorption-desorption isotherms, SEM and TEM images show that M-TiO_2-ns have high BET surface areas (85 and 120m~2/g, respectively), large pore volumes (0.32 and 0.34cm~3/g, respectively) and crystalline mesopore walls, which exhibit monolithic morphology with crystal sizes around 3-5 μm. Interestingly, M-TiO_2-ns exhibit much higher catalytic activities and good recyclability in both induced reduction of decabromodiphenyl and oxidation of Rhodamine B under UV light than those of nonporous crystalline TiO_2 and M-TiO_2 templated by hydrocarbon surfactant of F127, which is even comparable with that of commercial P25. Combination of the unique characters such as crystallinity, stable mesostructure, large BET surface areas and superior photo catalytic activities make M-TiO_2-ns a kind of potentially important material for removing of organic pollutions in environment through green photo irradiation processes.