光催化型TiO_2溶胶的制备和分析

Preparation and Analysis of Photocatalytic TiO_2 Sol

以sol-gel工艺,采用钛酸丁酯-水-无水乙醇-盐酸体系材料,以过量水强迫前驱体充分水解,制备出具有光催化性能的氧化钛晶体溶胶。通过XRD、TEM和UV/vis测试得知,溶胶中含有原位自生长的、边长约150nm的正方形锐钛矿晶体,所以溶胶在常温下干燥后所得粉体,无需高温热处理即为锐钛矿晶型;溶胶中晶体的禁带宽度为3.58eV,具有较强的光催化性,所以溶胶(而非常见的粉体或者薄膜)在紫外光照下可使罗丹明B褪色。

Photocatalytic TiO2 sol was prepared by sol-gel method, using Ti（OC4H9）4-H2O-anhydrC2H5OH-HCl reaction system, in which excessive water forces Ti（OC4H9）4 to hydrolyze thoroughly. Results of XRD, TEM, and UV/vis spectra show that there are in-site anatase crystals contained in the sol, which are 150 nm-width squares. Thus the powders drying the sol at room temperature show an anatase pattern, without any further heat treatment. The forbidden gap of the crystals in the sol is 3.58eV, which possess strong photocatalytic property, Because of the nano anatase crystals inside, the sols can photocatalyze rhodamine B under UV lights.