纳米TiO2的溶胶-凝胶法制备及其表征

以钛酸正丁酯（TNB）-去离子水-盐酸-乙酰丙酮（Acac）的乙醇溶液为反应体系，采用溶胶-凝胶法制备纳米TiO2溶胶颗粒。通过DLS、XRD和HRTEM等表征手段对TiO2颗粒的生成过程、其粒径和晶型的调控等方面进行研究。发现低温环境下TiO2的生成主要经历水解反应形成螯合物、缩合反应生成TiO2溶胶、TiO2溶胶颗粒融合这三个阶段。并且通过调节反应温度和催化剂浓度，可在无需高温锻烧的情况下，制得具有典型锐钛矿晶型的高分散性TiO2溶胶颗粒。

Preparation of Nano-TiO2 via Sol-Gel Method and Its Characterization

Nano-TiO2 sol particle is prepared by sol-gel method using the designed ethanol solution of butyl titanate （TNB）, deionized water, hydrochloric acid and acetylaeetone （Acac）. The generation process of TiO2 and its particle size and crystal are characterized by dynamic light scattering （DLS）, X-ray diffraction （XRD） and high resolution transmission electron microscope （HRTEM）. It is found that TiO2 generation process consists of three stages： hydrolysis reaction, condensation reaction, and sol-particle combination. The particle size and crystal can be controlled by reaction temperature and catalyst concentra- tion. Especially when the reaction temperature is 70℃, the amount of hydrochloric acid catalyst 0. 5mol/ L, the molar ratio of deionized water to TNB 4, a kind of nano-TiO2 sol particle with high dispersion and typical anatase crystal can be obtained just via a low-temperature sol-gel process.