Evidence of two ferroelectric PTCR components in valence-compensated ceramic system Ba1-xLaxTi1-xCoxO3

被引：12
作者：
Pandey, L
Katare, RK
Parkash, O
Kumar, D
机构：
[1] BANARAS HINDU UNIV, INST TECHNOL, SCH MAT SCI & TECHNOL, VARANASI 221005, UTTAR PRADESH, INDIA
[2] BANARAS HINDU UNIV, INST TECHNOL, DEPT CERAM ENGN, VARANASI 221005, UTTAR PRADESH, INDIA
[3] RANI DURGAVATI UNIV, DEPT PHYS, JABALPUR 482001, INDIA
[4] RANI DURGAVATI UNIV, CTR COMP, JABALPUR 482001, INDIA
来源：
BULLETIN OF MATERIALS SCIENCE | 1997年 / 20卷 / 07期
关键词：
PTCR; valence-compensated ceramic; impedance analysis;
D O I：
10.1007/BF02744882
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
The electrical behaviour of valence-compensated ceramic system Ba1-xLax Ti1-xCoxO3 has been studied as a function of temperature (300-600 K) and composition (x less than or equal to 0.20), using the method of impedance spectroscopy. The necessary equivalent circuit models that represent the data best have been obtained using impedance and modulus formalisms and grain and grain boundary contributions have been separated out. The compositions x = 0.20 and 0.10 show a negative temperature coefficient of resistance (NTCR) behaviour whereas a very small variation of the grain and grain boundary resistance with temperature is observed for x = 0.05. A positive temperature coefficient of resistance (PTCR) behaviour having two ferroelectric components is observed for x = 0.01. These results reveal limitations in current theories of the PTCR effect.
引用
收藏
页码：933 / 947
页数：15
相关论文
共 35 条
1234