Dielectric and electric relaxations induced by the complex defect clusters in (Yb plus Nb) co-doped rutile TiO2 ceramics
Dielectric and electric relaxations induced by the complex defect clusters in (Yb plus Nb) co-doped rutile TiO2 ceramics
复制标题
(Yb 加 Nb) 共掺杂金红石 TiO2 陶瓷中复杂缺陷簇引起的介电和电弛豫
DOI：
10.1111/jace.14861
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发表时间：
2017
影响因子：
3.9
通讯作者：
Liu Peng
中科院分区：
文献类型：
--
作者：
Zhao Xiao gang;Liu Peng
研究了Yb+Nb替代钛对(Yb1/2Nb1/2)xTi1−xO2(0.01≤x≤0.1)陶瓷的显微结构、晶体结构和介电性能的影响。结果表明，(Yb1/2Nb1/2)xTi1−xO2陶瓷的固溶度极限为x=0.07，平均晶粒度从12μm减小到6μm，x从0.0 1增加到0.1。在10-30 K、80-180 K和260-300 K温度范围内观察到三种类型的介电弛豫，它们分别是由电子钉扎缺陷偶极子、极化子跳跃和界面极化引起的。交流电导测量证实了其导电机制由近邻跳跃机制转变为极化子跳跃机制。本工作确定了该化合物的巨介电常数与极化子跳跃过程之间的关系。
The effect of the Yb+Nb substitution for Ti on the microstructure, crystal structures, and dielectric properties of (Yb1/2Nb1/2)xTi1−xO2(0.01≤x≤0.1) ceramics is investigated in this study. The results reveal that the solid solubility limit of the (Yb1/2Nb1/2)xTi1−xO2ceramics isx=0.07, and the average grain sizes considerably decrease from 12 μm to 6 μm withxincreasing from 0.01 to 0.1. Three types of dielectric relaxations are observed at temperature ranges of 10‐30 K, 80‐180 K, and 260‐300 K, caused by the electron‐pinned defect dipoles, polaron hopping, and interfacial polarizations, respectively. The conduction mechanism changes from nearest‐neighbor‐hopping to polaron hopping mechanism, which is confirmed by ac conductivity measurements. The present work indentifies the correlation between the colossal permittivity and polaron hopping process in the titled compound.