【摘要】 以Ti OSO4水溶液为前驱体,NH3·H2O为沉淀剂,聚乙二醇400(PEG400)为分散剂,在60~80℃下均相沉淀与结晶,制备出透明锐钛矿相二氧化钛溶胶。利用XRD和TEM表征了粉体的晶体结构和形貌。研究了制备过程中溶液中H+/Ti摩尔比、表面活性剂、晶化温度和时间对Ti O2溶胶颗粒尺寸的影响。结果表明:当溶液中H+/Ti摩尔比为5,晶化温度为70℃,分散剂质量分数为2.5%时,得到的二氧化钛晶粒尺寸在10~20nm之间。聚乙二醇400的加入有效抑制了晶化过程中晶粒的长大。更多还原

【Abstract】 Transparent anatase TiO₂ gel is successfully prepared by homogeneous precipitation and then crystallization at 60～80℃, using TiOSO₄ solution as precursor, ammonia solution as precipitant and polyethylene glycol as surfactant respectively. The crystal morphology and structure of nano-powders are characterized by TEM and XRD. The effects of experimental conditions such as pH value of solution, the mass fraction of surfactant and the crystallization temperature and time on crystal sizes of the gel are studied in detail. The results show that the particles are in spherical-like shape and the average size is 10～20nm at 70℃ when pH value is 0～4.0 and the mass fraction of surfactant is 2.5%. It is concluded that the shape and size of TiO₂ gel can be controlled and modified effectively by using surfactant,and the TiO₂ particles in colloid are anatase crystallites with good crystal lattices after dehydrated in acid media.更多还原