Ba(Ti_(1-x)Sn_x)O_3陶瓷的高温介电弛豫现象与阻抗研究  

High-temperature Dielectric Relaxation and Impedance Analysis of BaTi_(1-x)Sn_xO_3 Ceramics

作　　者：黄广 刘秋香[1] Huang Guang;Liu Qiu-xiang(School of Physics and Optoelectric Engineering, Guangdong University of Technology, Guangzhou 510006, China)

机构地区：[1]广东工业大学物理与光电工程学院,广东广州510006

出　　处：《广东工业大学学报》2017年第6期88-92,共5页Journal of Guangdong University of Technology

基　　金：广东省自然科学基金资助项目(2016A030313718)

摘　　要：通过传统的高温固相法制备了BaTi_(1-x)Sn_xO_3(x=0.02,0.10,0.15,0.25)陶瓷.XRD图显示,制备的所有样品的相都是单一的纯钙钛矿相.随着Sn4+/Ti4+的摩尔比的增大,样品的居里温度向低温方向移动.当x=0.02,0.10以及0.15时,阻抗谱显示主要是晶界对样品电阻的贡献.而当x=0.25时,则晶粒和晶界两者的贡献均不可忽略.介电谱和阻抗谱分析显示,介电计算出来的活化能比阻抗计算出来的活化能要低,表明高温弛豫的机理应该以偶极子传导为主,可以用氧空位的热动力学过程来解释.BaTi1-xSnxO3(x=0.02,0.10,0.15,0.25)ceramics were synthesized by the traditional solid state reaction method.XRD spectrum shows that all sample is tetragonal phase.With the increase of Sn4+/Ti4+molar ratio,Curie temperature of all compositions will drop a little.When x value range0.02to0.15,the impedance spectrum analysis shows that the sample resistance may be mainly ascribed to grain boundary.While for composition of x=0.25,the response from grain can not be ignored.Through analyzing the dielectric spectrum and impedance spectroscopy,the values of activation energy calculated from conduction were lower than that calculated from impedance measurements.The results suggest that the relaxation process of BaTi1-xSnxO3ceramics is dominated by a dipolar conduction.The conduction mechanism can be explained by thermal dynamic process of oxygen vacancy.

关 键 词：高温介电弛豫 阻抗 传导机理 

分 类 号：O469[理学—凝聚态物理]