室温制备TiO2多孔薄膜及其影响因素

将具有锐钛矿晶粒的TiO2溶胶与苯丙乳液混合制得涂膜液,采用浸渍提拉法制备薄膜,利用选择性溶解的方法将薄膜中的苯丙乳液粒子溶解去除,在室温下获得锐钛矿型TiO2多孔薄膜.采用TEM、SEM等分析方法考察了TiO2溶胶添加量、苯丙乳液添加量、涂膜液陈化时间以及乳液粒子溶解去除条件等因素对TiO2薄膜表面形貌的影响.结果表明涂膜液中TiO2溶胶与苯丙乳液添加量的比例影响了孔的形态;涂膜液的陈化时间是影响薄膜表面孔致密程度的关键因素,陈化时间的增长有利于薄膜表面形成较为密集的孔洞;采用超声波能大大提高薄膜中苯丙乳液粒子的去除效率.最后得出了制备TiO2多孔薄膜的较为合适的涂膜液配比及工艺条件：15g TiO2溶胶、0.2g苯丙乳液、10g H2O;涂膜液陈化15d,薄膜浸入甲苯后,超声波振荡10min.

Influence of Factors on Porous TiO2 Films Prepared at Room Temperature

A solution consisting of styrene-acrylate spheres and anatase TiO₂ colloidal particles was synthesized. The films were prepared from resultant solution by a dip-coating technique, and then styrene-acrylate spheres were preferentially dissolved in toluene, and the porous anatase TiO₂ films were obtained at room temperature. Transmission electron microscope (TEM) and scanning electron microscope (SEM) were adopted to analyze the influence of the styrene-acrylate emulsion consumption, the dosage of TiO₂ sol, the aging time of the solutions and the conditions of eliminating styrene-acrylate spheres on the morphology of the films. The results show that the mass ratio of TiO₂ sol and styrene-acrylate emulsion affects the morphology of the pores; the aging time is a dominant factor for the formation of the dense pores on the surface; styrene-acrylate spheres can be eliminated effectively by the ultrasonic oscillation. The results also indicate that the appropriate proportion is: 15g TiO₂ sol+0.2g styrene-acrylate emulsion+10g H₂O; the solutions are aged for 15d, and the films are soaked into toluene and vibrated by ultrasonic for 10min.