(浙江工业大学 化学工程与材料学院,杭州 310014)
摘 要: 以硝酸锶和钛酸丁酯为原料,采用溶胶凝胶法制备了钙钛矿型纳米SrTiO3。采用红外光谱、差热分析、X射线衍射、扫描电镜及紫外吸收等测试手段,研究了影响溶胶凝胶过程的诸因素,对制备的SrTiO3粉体的结构和性质进行了表征。结果表明:乙醇、冰醋酸、水、丙三醇、温度及pH值均对溶胶凝胶过程有明显影响,其中反应温度对胶体形成时间长短和胶体质量影响最明显。钙钛矿型SrTiO3晶体于650 ℃时生成,随着热处理温度的升高,粉体的物相组成将发生变化,粉体的尺寸也有所增加,相应的紫外吸收峰也出现红移现象。
关键字: 钙钛矿型催化剂;钛酸锶; 溶胶-凝胶;晶体结构
by sol-gel process
(College of Chemical Engineering and Material Science,
Zhejiang University of Technology, Hangzhou 310014, China)
Abstract: By using Sr(NO3)2 and Ti(OBu)4 as raw materials, nano-sized SrTiO3 powder was prepared by the sol-gel process. By means of IR, TG-DTA, XRD, SEM and UV analysis, the different factors affecting the sol-gel process were investigated, and the crystal structure and characteristics of the as-prepared SrTiO3 powder were analyzed. The experimental results show that the factors including alcohol, acetic acid, water, propyl alcohol, temperature and pH value have obvious influence in sol-gel process, especially, in which the reaction temperature is the most important factor for the gelation time and quality of the gel. Perovskite SrTiO3 is formed at heat treatment temperature of 650 ℃. With the increase of heat treatment temperature, the phase abundance of SrTiO3 is improved and the SrTiO3 crystal grows as well. A red shift phenomenon is observed in UV spectrum for the corresponding powder.
Key words: perovskite catalyst; strontium titanate; sol-gel; crystal structure