过渡金属掺杂BaTiO_3的晶格结构和相变特性  

Crystal Structure and Phase-transition Characters of Transition-metal-doping Barium Titanate

作　　者：曹鸿霞[1] 王婷婷[1] 王友保[1] 

机构地区：[1]江苏省气象探测与信息处理重点实验室,南京信息工程大学电子与信息工程学院,南京210044

出　　处：《陶瓷》2012年第9期17-21,共5页Ceramics

基　　金：国家自然科学基金(批准号:61072137);南京信息工程大学科研基金(项目编号:20100352)

摘　　要：采用溶胶-凝胶法制备纯净BaTiO3,将1.0mol%的Cr、Fe、Mn、Co掺杂BaTiO3和浓度分别为1.25mol%、1.5mol%、1.75mol%、2.0mol%的Fe掺杂BaTiO3前驱粉体,经热压烧结,并在1350℃下烧结成多晶陶瓷样品。对样品进行XRD和DSC表征的研究。分析了掺杂离子种类和浓度对样品的晶格四方性、相变温度(居里点)和相变潜热的影响。分析结果表明,掺杂BaTiO3的四方性、居里点和相变潜热低于纯净BaTiO3且随Cr、Fe、Mn、Co的掺杂顺序以及Fe掺杂浓度的增加而减少。过渡元素掺杂BaTiO3的居里点和相变潜热随晶格四方性的降低逐渐减小。Pure barium titanate BaTiO3,1.0mol% Cr,Fe,Mn, Co-doped and 1.25 mol% ,1.5 mol% ,1.75 mol% ,2.0 mol% Fe doped BaTiO3 polycrystalline ceramic samples were synthesized with sol-gel and hot-pressing techniques. X--ray diffraction and differenti- al scanning calorimetry were used to characterize the barium titanate samples. The influence of doping ionic and doping concentration on crystal tetragonality,Curie point and latent heat was analyzed. The results show that tetragonality, curie point and latent heat＇of doped BaTiO3 less than that of pure BaTiO3 and decrease with Cr, Fe, Mn, Co doping and increasing Fe doping concentration. Curie point and latent heat of transition--metal-doped BaTiOs drop with decreasing tetragonality.

关 键 词：掺杂BaTiO3 晶格四方性 居里点 相变潜热 

分 类 号：TB303[一般工业技术—材料科学与工程]