钙钛矿型La_(0.1)Sr_(0.9)Co_(0.9)Fe_(0.1)O_(3-δ)膜的非化学计量及氧渗透模型  

Oxygen Nonstoichiometry and Oxygen Permeation Model of Perovskite-Type La_(0.1)Sr_(0.9)Co_(0.9)Fe_(0.1)O_(3-δ) Membrane

作　　者：袁文辉[1] 罗仡科[1] 李莉[1] 

机构地区：[1]华南理工大学化工与能源学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2007年第4期16-19,共4页Journal of South China University of Technology(Natural Science Edition)

基　　金：教育部留学基金;教育部传热与节能重点实验室基金资助项目;广东省自然科学基金资助项目(04020126)

摘　　要：钙钛矿型透氧膜的非化学计量平衡关系与氧分压和温度有关,并对其应用起决定作用.文中以金属硝酸盐为前驱体,采用EDTA-柠檬酸联合络合法制备了钙钛矿型氧化物La0.1Sr0.9Co0.9Fe0.1O3-δ,并利用TG/DSC、XRD、SEM等方法对La0.1Sr0.9Co0.9Fe0.1O3-δ粉体的晶体结构和表面形态进行了表征.温度在923～1223K、压力在0.101～1.01×10^5Pa之间变化时,采用热重分析法测得La0.1Sr0.9Co0.9Fe0.1O3-δ的非化学计量值在0.33～0.51之间.文中还利用简化的半经验公式对非化学计量值δ进行了计算,发现半经验公式能很好地与实验数据相拟合,由此得到了一个氧渗透通量的计算模型.实验结果表明,所提出的模型能够较好地预测La0.1Sr0.9Co0.9Fe0.1O3-δ膜的氧渗透通量.The equilibrium relationship of the oxygen nonstoichiometry of perovskite-type ceramic membrane is known to be related to the partial oxygen pressure and the temperature, and has proved to be critical to the applications of the ceramic. In this paper, a perovskite-type La0.1Sr0.9 Co0.9 Fe0.1O3-δ oxide ceramic was synthesized by means of EDTA-citrate complex method, and the crystal structure and morphology of the produced ceramic powder were characterized by TG/DSC, XRD and SEM. The oxygen nostoichiometry 8 in the range of 0.33 ～ 0.51 was then obtained by TGA at 923 ～ 1223 K with the pressure varying from 0. 101 Pa to 1.01 × 10^5 Pa. Moreover, a simplified semi-empirical equation was used to calculate the oxygen nostoichiometry, It was found that the equation accords very well with the measured oxygen nonstoichiometry. Based on the semi-empirical equation, a model to predict the oxygen permeation flux was finallv obtained, whose effectiveness was verified by experiments.

关 键 词：氧 非化学计量 钙钛矿型陶瓷膜 氧渗透 模型 

分 类 号：TQ174[化学工程—陶瓷工业] TB383[化学工程—硅酸盐工业]