在水/环己烷微乳体系中制备纳米级氧化锆微粒

研究了在水 环己烷 正己醇 Triton X 100的微乳体系中, 几种主要实验参数对由氯氧化锆制备氧化锆纳米粒子的比表面积及其颗粒大小的影响.实验结果表明，微乳体系中水与表面活性剂的摩尔比ro、氯氧化锆的浓度以及微乳沉淀反应的温度都对氧化锆的比表面积有很大影响.在不同温度的微乳体系，氯氧化锆浓度对最终氧化锆粒子的比表面积的影响不同.通过优化制备条件，制得了比表面积为212 m2•g－1（450 ℃焙烧后）的氧化锆纳米粉体.文中还对所制备的氧化锆样品进行了X射线衍射(XRD)、透射电镜（TEM）和氮气吸附的分析.

Preparation of Zirconia Zanoparticles in Reverse Microemulsion

A variety of synthesis parameters for the preparation of Zirconia nanoparticles in water cylcohexane hexanol Triton X 100 microemulsion have been investigated. The results show that reaction temperatures and the molar ratio of water to surfactant(r0) were the predominant factors to control the specific surface area as well as particle sizes of ZrO2 . The particle size first decreased with a decrease in the value of r0, then increased after reaching a critical particle size upon further decreasing the r0 value; on the other hand, an increase in the reaction temperature led to smaller ZrO2 particles, but the ZrO2 particle size became larger at a temperature close to the cloud point of the reverse micelles, where a small temperature disturbance would easily lead the system out of the microemulsion phase. XRD, TEM and N2 adsorption experiments were used to characterize the ZrO2 sample. XRD results showed that the fresh sample was amorphous, and tetragonal phase appeared as a predominant phase with a little monoclinic modification upon calcining the sample at 450 ℃, further heating the sample at 900 ℃ would lead to more monoclinic modification in intensity, but tetragonal phase was still predominant. TEM showed that the average particle size was increased from about 4 nm at 450 ℃ to about 21 nm at 900 ℃, which was in agreement with the measurements from N2 adsorption results and XRD results. N2 adsorption experiments indicated that a specific surface area of 212 m2•g－1 was obtained after optimizing the synthesis parameters and calcining the obtained sample at 450 ℃ in oxygen.