VALENCE CHANGE OF MN IONS IN BATIO3-BASED PTCR MATERIALS

被引：37

作者：

LEE, JH

KIM, SH

CHO, SH

机构：

[1] Department of Inorganic Materials Engineering, Kyungpook National University, Taegu

来源：

JOURNAL OF THE AMERICAN CERAMIC SOCIETY | 1995年 / 78卷 / 10期

关键词：

D O I：

10.1111/j.1151-2916.1995.tb08065.x

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

The effect of Mn on the PTCR characteristics of La-doped BaTiO3 ceramics was studied, Acceptor state density was measured from a rho-1/T graph as a function of Mn concentration. The behavior of room-temperature resistivity with Mn concentration was explained by compensation of accepters at grain boundaries. The valence state of Mn was analyzed by ESR, and it changed near the Curie temperature of BaTiO3 from 3+ in tetragonal phase to 2+ in cubic phase. Therefore, the number of electron traps increased at the Curie temperature, leading to the great improvement in the PTCR effect. The valence change of Mn ions was explained by vanishing of the Jahn-Teller effect as the phase changes from tetragonal to cubic.

引用

页码：2845 / 2848

页数：4

共 27 条

[1] MN-DOPED POLYCRYSTALLINE BATIO3 [J].