采用低温水热法,以离子液体-水为混合溶剂制备了TiO2纳米颗粒,用XRD,TEM,SAED,N2吸附等技术对产物进行了表征,研究了离子液体对TiO2的晶形、结晶度、晶粒尺寸等结构特点的影响;结果表明:体系中离子液体的含量对TiO2的结晶度、晶粒尺寸有很大影响.当体系中离子液体含量低于水量时,增加离子液体可促进TiO2结晶,反之,则抑制TiO2结晶;在VIL/(VIL+VH2O)=0.5时所得产物有最高锐钛矿相结晶度.此外,在一定范围内,离子液体可调控TiO2的晶粒尺寸.从离子液体-水溶液的粘度、电导率及溶液微结构变化等方面讨论了离子液体对TiO2形成的影响.
A low -temperature hydrothermal method with room temperature ionic liquid (IL, 1 -ethyl -3 - methyl -imidazole acetate) and water mixture as solvent was used to prepare nanocrystalline TiO2 powders. The crystal phase, morphology, and grain size of the products were characterized by using X - ray diffraction ( XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) techniques. It was found that high crystalline anatase TiO2 nanoparticles could be obtained at specific IL concentrations. When IL volume fraction was 〈 0.5, crystallization of TiO2 could be enhanced with increasing the amount of IL in reaction medium, and vice versa. Besides, grain size of TiO2 nanoparticles could be tuned in a certain extent by changing the ratio of water and IL. These results were thought to be related with the ionic strength, viscosity and micro - structure of IL - water solution.