硬脂酸溶胶凝胶法-共沸蒸馏法制备钙钛矿型纳米LaCoO3  

Preparation of Nanometer Sized Powder LaCoO_3 via Stearic Acid Sol-Gel

作　　者：刘海燕[1] 王燕[1] 张学俊[1] 李延斌[1] 逯宝娣[2] 卫芝贤[1] 

机构地区：[1]中北大学理学院化学系,山西太原030051 [2]太原科技大学化学与生物工程学院,山西太原030021

出　　处：《稀有金属》2009年第1期57-61,共5页Chinese Journal of Rare Metals

基　　金：2006年兵器青年创新基金项目;国家自然科学基金(20671084)资助项目

摘　　要：用硬脂酸溶胶凝胶-共沸蒸馏法制备了纳米LaCoO3,用差热-热重、透射电镜及红外等手段对粉体进行了表征,并对配合物溶胶-共沸蒸馏脱水的干燥机制进行了探讨。实验结果表明:硬脂酸溶胶凝胶法制备纳米粉体时,配合物溶胶的干燥脱水是不可缺少的一步。共沸蒸馏所用的溶剂苯是通过物理吸附作用替代了配合物溶胶中的水,其机理是靠降低粒子间毛细管力来减少聚集作用的,从而防止了干燥及后续煅烧阶段的粉体团聚。Nanometer sized perovskite-type LaCoO3 was prepared by sol-gel method using stearic acid as a complexing agent. The products were characterized by differential thermal analyzer and thermal gravimetric （DTA-TG） , FT-IR spectra, X-ray powder diffraction （XRD） and transmission electron microscope （ TEM ）. Complex sol was dehydrated by heterogeneous azeotroic distillation process of the system consisting of the sol and benzene. The dehydrated mechanism of complex sol was investigated. The experimental results showed that it was necessary for complex sol to be dehydrated in order to obtain nanometer sized LaCoO3 powders. Benze.ne as a solvent in the azeotroic distillation process could effectively prevent nano-particles from hard agglomeration during the drying process and the mechanism may be attributed to the decrease of capillary force among the particles during the drying proce：ss because of the substitution of organism ben zene for water.

关 键 词：纳米LaCoO3 硬脂酸溶胶-凝胶法 干燥机制 

分 类 号：O614.43[理学—无机化学] O643[理学—化学]