Preparation and Mechanism of Li4Ti5O12 by Sol-gel Method Yang Jianwen, Zhong Hui, Zhong Haiyun, Dai Yanyang, Zhao Xuan (College of Metallurgical Science and Engineering, Central South University, Changsha 410083) Abstract Spinel Li4Ti5O12 was prepared by sol-gel method with citric acid, titanium salt, lithium hydroxide, and the formation mechanism of Li4Ti5O12 was studied. According to IR, TGA-DTA , XRD and SEM analysis, the precursors using or without using organic crosslinking agent had similar combinative characters. Citrate could coordinate with Ti(Ⅳ) through a monodentate, and there were [-O-Ti-O-]n chains in the precursors. In air, thermal decomposition of precursors involved in organic and carbon chains oxidation, and Li4Ti5O12 crystal formation and growth. Single phase nanocrystalline Li4Ti5O12 were made at 700℃, and ana-TiO2 intermediate phase was experienced. The Li4Ti5O12 powders made at 800℃ were porous and loose aggregates, and fine particle size distribution. Key words Li4Ti5O12, Sol-gel method, Mechanism of formation Li4Ti5O12的溶胶-凝胶法制备及形成机理 杨建文 钟晖 钟海云 戴艳阳 赵绚 (中南大学冶金科学与工程学院 长沙 410083) 摘要 用溶胶-凝胶法合成了纯尖晶石相纳米晶Li4Ti5O12，并对其形成机理进行了研究。IF分析表明，水相中与有机交联剂介质中合成的前驱体结构非常相似，柠檬酸根与Ti(Ⅳ)为单齿方式配位，钛与氧形成了[－O－Ti－O－]n聚合链；TG-DTA和XRD分析表明，前驱体热分解经历了有机物热分解、碳链断裂燃烧与Li4Ti5O12形成及晶形成长等阶段；前驱体在热分解的同时就形成了Li4Ti5O12，钛元素在反应过程中经历了锐钛矿型-TiO2中间相，700℃时已成为单一相纳米晶Li4Ti5O12；800℃合成粉末的SEM研究表明，产物粒度分布均匀，为球形颗粒的疏松多孔聚集体。 关键词 Li4Ti5O12 溶胶-凝胶法 形成机理 杨建文 男，36岁，博士生，现从事电化学电容器研究。*联系人 2004-02-23收稿，2004-06-20接受 (PDF全文下载c04107)