乳液辅助水热法合成TiO_2微球光催化剂

TiO_2 microsphere photocatalyst prepared by emulsion assisted hydrothermal method

采用乳液辅助水热法,以钛酸四正丁酯为原料,乙酰丙酮为水解抑制剂、十二烷基苯磺酸为表面活性剂,制备高孔隙率的多孔锐钛矿型TiO_2微球。通过对各时间段样品的SEM及XRD分析,考察了TiO_2微球的形成机理。乳液中分散的钛酸四正丁酯球形液滴经凝胶化及晶化过程转化为介孔结构的TiO_2微球。水热条件下微球的结晶化是其显示高光催化活性的主要因素,合适的水热反应时间是进一步提高样品光催化活性的重要条件。反应温度150℃、时间为5 h时,获得的TiO_2微球样品其比表面积与气孔体积分别达到145 m^2/g及0.29 cm^3/g,显示了较高的光催化活性。

High porous anatase TiO2 microspheres were prepared by emulsion assisted hydrothermal method, using tetrabutyl titanate as starting raw material, aeetyl acetone as hydrolysis inhibitor and dodecylbenzene sulfonic acid as surfactant agent. The formation mechanism of products was investigated based on the SEM and XRD analysis the with different reaction time. The dispersed spherical droplets of tetrabutyl titanate transformed into mesoporous TiO2 microspheres through gelatinization and subsequent crystallization process. The crystallization of microspheres during hydrothermal process was a key for obtaining high photocatalytic activity ,and a appropriate hydrothermal time can further enhance the photocatalytic activity. The TiO2microspheres produced at 150℃ for 5 h,the specific surface area and pore volume reached 145 m^2/g and 0.29 cm^3/g,respectively,showed higher photocatalytic activity. Key words titania microsphere, hydrothermal method, emulsion, photocatalytic activity