摘要
通过对克劳修斯-莫索蒂方程的近似,分析了钙钛矿结构微波介质陶瓷频率温度系数(τf)的主要影响因素,发现改变材料介电响应中离子位移极化和电子位移极化的比例,可调节频率温度系数的正负与大小.通过电子结构计算和容忍因子分析,预测引入(Zn1/3Nb2/3)4+对具有正温度系数的CaTiO3进行B位取代将提高材料电子极化响应比例,调节τf由正变负.采用偏铌酸盐为前驱体,通过固相反应法合成了Ca[(Zn1/3Nb2/3)xTi(1-x)]O3钙钛矿结构陶瓷,并对其进行结构分析和性能测试,实验结果与理论分析一致,获得了具有近零频率温度系数的Ca[(Zn1/3Nb2/3)0.7Ti0.3]O3介质陶瓷材料.
The determinants of resonant frequency temperature coefficient （τf） have been analyzed by the approximate treatment of Clausius- Mossotti equation. It is suggested that the value of τf can be adjusted by changing the contribution proportion of ionic polarization or electronic polarization for the dielectric constant. Results of electronic structure calculation and tolerance factor analysis show that B- site substitution of CaTiO3 with （Znl/3Nb2/3）4＋ could turn the value of τf from positive to negative, by enhancing the covalency in the BO6 octahedron and improving the contribution proportion of electronic polarization. Ca[（Zn1/3Nb2/3）xTi（1-x）]O3 dielectric ceramics were prepared by solid-state reaction method with niobate as precursor. Results of structure analysis and property measurement conform to the theoretical analysis. The Ca[（Znl/3Nb2/3）0.7Ti0.3]O3 dielectric ceramic with near-zero τf was obtained.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第11期480-485,共6页
Acta Physica Sinica
基金
国家自然科学基金重点(批准号:50932004)
国家自然科学基金项目(批准号:51102191
51072148)
国家自然科学基金国际(地区)合作与交流项目(批准号:51161140399)
教育部新世纪优秀人才支持计划(批准号:NCET-09-0628)
教育部高等学校博士学科点专项科研基金项目(批准号:20101431200172010)
中央高校基本科研业务费专项资金(批准号:2012-II-016)
武汉市科学技术计划项目(批准号:2013010501010137)资助的课题~~
关键词
B位复合钙钛矿陶瓷
谐振频率温度稳定性
极化机理
BO6八面体倾斜
B-site complex perovskite ceramics, resonant frequency-temperature stability, polarization, BO6octahedron tilting
