B位Cr替代对BiFeO3介电特性的影响  

The influence of Cr substitution on the dielectric properties of BiFeO3 ceramics

作　　者：常方高[1] 张娜[1] 杨枫[1] 王绍祥[1] 

机构地区：[1]河南师范大学物理与信息工程学院,河南新乡453007

出　　处：《功能材料》2007年第A02期456-458,共3页Journal of Functional Materials

基　　金：国家自然科学基金资助项目（60571063）;留学归国基金资助项目（教外司留[2005]55）.

摘　　要：采用传统的固相反应法制备了BiFe1-xCrO3（x=0，0．01，0．1,0．3，0．5）系列陶瓷样品，运用X射线衍射仪对样品进行结构分析发现，随着Cr含量的增加BiFeO3的微观结构发生了改变；利用HP3458A型万用表在室温下测量样品的电阻率随Cr含量的变化关系发现适当的Cr替代可以在一定程度上提高样品的电阻率；室温下利用HP4294A型阻抗分析仪在100Hz～100kHz的频率范围内测试样品的介电性能随频率的变化关系，结果表明介电常数岛随着Cr替代量的增加先增大然后又减小，而tanδ则随着Cr替代量的增加出现了较为复杂的变化．BiFe1-xCrO3ceramics with x=0,0.01,0.1,0.3,0.5 were prepared using conventional solid state reaction method. X-ray diffraction was carried out to characterize the crystal structure of the samples. The results indicate that the microstructure of BiFeO3 is changed by Cr substitution. Resistivity measurements revealed that proper Cr doping can increase the resistivity of BiFeO3. Frequency dependences of dielectric properties of BiFe1-xCrO3 samples at room temperature were measured in a frequency range from lOOHz to 100 kHz using a HP4294A precision impedance analyzer. The dielectric constant εr of BiFe1-xCrO3 samples increases with Cr content （x） when x is small, but decreases at higher x values. The dielectric loss tanδ varies with Cr content in a more complicated manner.

关 键 词：X射线衍射 电阻率 介电特性 

分 类 号：O469[理学—凝聚态物理]