溶胶-凝胶法低温合成硅酸锆粉体

摘要

Zircon powders were prepared by sol-gel method at low temperature using zirconium oxychloride and tetraethoxysilane as raw materials,deionized water and ethanol as dissolvants,NaF as a mineralizer to promote crystallization of zircon powder. The characterization techniques such as XRD and SEM are used to analyze the phase composition and the microstructures. The results show that the original synthesis temperature of zircon is as high as 1250℃ without the introduction of any mineralizers to precursor sols,when the temperature is raised up to 1500℃,the synthesis ratio of zircon powder is not very high,however,by adding sodium fluoride as a mineralizer to the sols,the crystalline phase of zircon appears at 550℃ and the zircon powder which is calcined at the temperature of 800℃ not only has a high synthesis ratio,but also shows good crystallinity.%采用溶胶-凝胶法(sol-gel)合成ZrSiO4粉体,以正硅酸乙酯[Si(OC2H5)4]和氧氯化锆(ZrOCl2·8H2O)为原料,无水乙醇和去离子水为溶剂,氟化钠为矿化剂,并借助XRD、SEM等测试手段分析了合成样品的晶相组成及其微观形貌.结果表明:没有引入矿化剂的样品,合成硅酸锆的初始温度高达1250 ℃以上,当温度达到1500 ℃时,硅酸锆的合成率也不是很高;然而,在溶胶中引入矿化剂NaF后,前驱体热处理温度为550 ℃时,粉体中开始有ZrSiO4的晶相生成,当温度升高至800 ℃时,硅酸锆的晶相含量已经很高,结晶程度很好.