熔盐法合成烧绿石结构La_2Zr_2O_7粉体  

La_2Zr_2O_7 Powder with Pyrochlore Structure by Molten Salt Synthesis

作　　者：黄仲[1] 李赛赛[1] 谭操[1] 刘江昊[1] 鲁礼林[1] 张少伟[1] 张海军[1] 

机构地区：[1]武汉科技大学材料与冶金学院省部共建耐火材料与冶金国家重点实验室,武汉430081

出　　处：《机械工程材料》2016年第6期55-58,共4页Materials For Mechanical Engineering

基　　金："973"计划前期研究专项(2014CB660802);国家自然科学基金面上资助项目(51272188;51472184;51472185);湖北省自然科学基金重点资助项目(2013CFA086);湖北省科技支撑计划对外科技合作项目(2013BHE002)

摘　　要：以氧化锆和氧化镧为反应原料,以氯化钾-氯化锂为熔盐介质,采用熔盐法制备了烧绿石结构锆酸镧（La2Zr2O7）粉体,研究了反应温度和熔盐含量对该粉体纯度的影响,并分析了其显微结构。结果表明：La2Zr2O7粉体除了由原料直接反应合成外,还有部分是由La2O3与熔盐先生成中间产物LaOCl,该中间产物再与ZrO2反应而生成;La2Zr2O7相的生成量随反应温度的升高而增加,随熔盐含量的增加先增后减;当熔盐与反应原料的质量比为3∶1时,在1 200℃下反应3h后可以合成纯La2Zr2O7相的粉体,其形貌与原料ZrO2粉体的基本相似,呈无规则颗粒状,晶粒大小为80~200nm。The La2Zr2O7 powders with pyrochlore structure were synthesized by the molten salt method with zirconium oxide and lanthanum oxide as reaction materials and with potassium chloride and lithium chloride as reaction media.The influences of reaction temperatures and molten salt content on the powder purity were investigated and the microstructures of the prepared powders was analyzed.The results show that apart from that directly prepared by the reaction materials,the La2Zr2O7 powders were also synthesized by the reaction of ZrO2 powder with intermediate product of LaOCl produced by the reaction of La2O3 powder with molten salts.The production of La2Zr2O7 phase increased with the increase of the reaction temperature and first increased then decreased with the molten salt content increase.Pure La2Zr2O7 powder was obtained under the condition of reaction at 1 200 ℃for 3hwith the mass ratio of molten salt to reaction material of 3∶1.The morphology of the prepared La2Zr2O7 powder was similar to that of raw material ZrO2 powder,showing an irregular particle shape with grain sizes of 80-200 nm.

关 键 词：烧绿石结构 LA2ZR2O7 熔盐法 反应温度 显微结构 

分 类 号：TQ174[化学工程—陶瓷工业]