物理化学学报 >> 2005, Vol. 21 >> Issue (10): 1122-1126.doi: 10.3866/PKU.WHXB20051012

研究论文 上一篇    下一篇

稀土元素Sm、Eu、Gd对Nb掺杂的TiO2压敏电阻电性能的影响

唐子龙; 米佳; 张中太; 周志刚   

  1. 清华大学材料科学与工程系, 新型陶瓷与精细工艺国家重点实验室, 北京 100084
  • 收稿日期:2005-03-21 修回日期:2005-05-09 发布日期:2005-10-15
  • 通讯作者: 唐子龙 E-mail:tzl@tsinghua.edu.cn

Effect of Sm, Eu and Gd on Nb- doped TiO2 Varistors

TANG Zi-long ; MI Jia; ZHANG Zhong-tai; ZHOU Zhi-gang   

  1. State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084
  • Received:2005-03-21 Revised:2005-05-09 Published:2005-10-15
  • Contact: TANG Zi-long E-mail:tzl@tsinghua.edu.cn

摘要: 研究了稀土元素Sm、Eu、Gd对于Nb掺杂的TiO2基压敏电阻电学性能的影响. 几种稀土元素的掺杂量均为体系总量的2%(原子比), 其它原料的掺入量固定不变. 实验样品在1380 ℃烧结, 保温4 h. 实验发现, Sm、Eu、Gd等稀土元素可以有效降低TiO2基压敏电阻的压敏电压, 但对于非线性系数的影响不很明显. 对于Sm、Eu、Gd掺杂, 实验得到的压敏电压值分别为12.7、14.7和16.1 V. 通过对试样的阻抗分析发现, Sm、Eu、Gd掺杂对于压敏电阻的介电性能有显著影响, 单独掺杂Sm或Gd的试样具有很低的介电常数和介电损耗, 并且具有很高的电阻率.

关键词: 压敏电阻, 稀土, 掺杂, TiO2, 缺陷

Abstract: The effect of Sm, Eu and Gd on electrical properties of a new class of polystalline ceramics based on TiO2 was investigated. The content of added Sm, Eu and Gd is 2% (atomic ratio), while that of the other addition is always maintained at a constant value. The disks were sintered at 1380 ℃ for 4 h. It was found that Sm, Eu and Gd can reduce the voltage values (corresponding to 1 mA current) of TiO2-based varistors effectively, but do not strongly influence the nonlinear values. The voltage values of the doped TiO2-based varistors were 12.7 V (Sm doped), 14.7 V (Eu doped) and 16.1 V (Gd doped). Through impedance analysis, it can be found that those rare-earth ions have great influence on the dielectric properties; the single addition of Sm or Gd could attain very low dielectric constant, low dissipation factor and very high resistivity. Sm, Eu and Gd distribute surrounding the TiO2 grains, but discontinuously.

Key words: Varistor, Rare- earth ions, Doping, Titania, Defect