硅酸盐学报2008，Vol.36Issue(7)：994-999,6.
采用二步法合成核-壳型二氧化硅/二氧化铈复合微粒
SYNTHESIS OF SILICON DIOXIDE/CERIUM OXIDE CORE-SHELL COMPOSITE ULTRAFINE PARTICLES BY TWO-STEP METHOD
摘要
Abstract
In absolute ethanolas solvent, SiO2 ultrafine particles were prepared by sol-gel method using tetraethylorthosilicate as silicon resource, ammonia as catalyst and calcining at 500 ℃ for 1 h. The effect of the ratio of the materials on the particle size and distribution of SiO2 particles were researched by the laser particle size analysis. SiO2/CeO2 core-shell composite ultrafine particles were successfully synthesized by the controlling reaction factors and using the chemical precipitation method with sodium dodecyl benzene sulfonate as dispersant, cerium nitrate as cerium resource, ammonium carbonate as precipitating agent and SiO2 ultrafme particles as cores, and calcinating at 300℃ for 1 h. The structures, composition and properties of the samples were analyzed by differential scanning calorimetry-thermal gravimetric analysis, X-ray diffraction, infrared spectrometry, scanning electron microscopy, transmission electron microscopy, energy dispersive analysis and zeta potential testing. The results indicate that the SiO2/CeO2 core-shell composite ultrafine particles have an excellent spherical morphology and uniform particle size. Their diameter is about 300-350 nm. A CeO2 can be primarily coated onto the surface of SiO2 ultrafine particle to form a shell, with a little CeO2 deposition on the SiO2 core. The thickness of the CeO2 shell is about 30 nm. After the coating has been deposited, the surface electric characteristics of the SiO2/CeO2 core-shell particles changes. The pH value at isoelectric point of the core-shell SiO2/CeO2 composite ultrafine particles increases from 2.2 for SiO2 paticles to 5.5, it is almost the same as that of CeO2 particles (pH=6.7).关键词
壳-核结构/二氧化硅/二氧化铈复合微粒/溶胶-凝胶法/化学沉淀法/二步法/化学机械抛光磨料/等电点Key words
core-shell structure/ silicon dioxide/cerium oxide composite ultrafine particles/ sol-gel method/ chemical precipitationmethod/ two-step method/ chemical mechanical polishing abrasive/ isoelectric point分类
通用工业技术引用本文复制引用
宋晓岚,江楠,刘东锋,李宇焜,邱冠周..采用二步法合成核-壳型二氧化硅/二氧化铈复合微粒[J].硅酸盐学报,2008,36(7):994-999,6.基金项目
科技部国际科技合作(2005DFBA028) （2005DFBA028）
中南大学大学生创新教育(LA06030)资助项目. （LA06030）
