Dielectric relaxations in multiferroic La2Ti2O7 ceramics

被引：21
作者：
Zhang, N. [1 ]
Li, Q. J. [1 ]
Huang, S. G. [1 ]
Yu, Y. [1 ]
Zheng, J. [2 ]
Cheng, C. [2 ]
Wang, C. C. [1 ]
机构：
[1] Anhui Univ, Lab Dielectr Funct Mat, Sch Phys & Mat Sci, Hefei 230601, Peoples R China
[2] Anhui Univ, Ctr Modern Expt Technol, Hefei 230039, Peoples R China
来源：
JOURNAL OF ALLOYS AND COMPOUNDS | 2015年 / 652卷
基金：
中国国家自然科学基金; 中国博士后科学基金;
关键词：
Dielectric property; Electric modulus; Cationic vacancies; Conduction progress; Oxygen vacancies; PIEZOELECTRIC PROPERTIES; LN(2)TI(2)O(7) LN; LA; PYROCHLORE; CONDUCTION; BEHAVIOR;
D O I：
10.1016/j.jallcom.2015.08.169
中图分类号：
O64 [物理化学（理论化学）、化学物理学];
学科分类号：
070304 ; 081704 ;
摘要：
La2Ti2O7 ceramic samples were prepared via conventional solid-state reaction route. The dielectric properties of La2Ti2O7 were investigated as functions of temperature (113-1073 K) and frequency (100 Hz(-1) MHz). Our results revealed that La2Ti2O7 ceramics exhibit intrinsic dielectric response with a dielectric constant of similar to 57 in the temperature range below 250 K. Three thermally activated dielectric relaxations were observed when the temperature higher than 250 K. The low-temperature relaxations R1 with the activation energy of 0.38 eV is found to be a polaron relaxation results from hopping holes. The high-temperature relaxations R2 and R3 are related to the conduction progress associated with the singly and doubly ionized oxygen vacancies, respectively. (C) 2015 Elsevier B.V. All rights reserved.
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页码：1 / 8
页数：8
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