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过程工程学报 ›› 2021, Vol. 21 ›› Issue (2): 210-218.DOI: 10.12034/j.issn.1009-606X.220023

• 材料工程 • 上一篇    下一篇

(Ca, Ta)共掺杂TiO2陶瓷巨介电性能及机理

崔 冰， 陈 继， 杨在志， 赵伟雨， 邓玉军， 郁 倩， 刘 娟， 徐 东*   

  1. 安徽工业大学材料科学与工程学院，安徽 马鞍山 243002
  • 收稿日期:2020-01-14 修回日期:2020-05-09 出版日期:2021-02-22 发布日期:2021-03-01
  • 通讯作者: 徐东 frank@shu.edu.cn

Giant dielectric properties and mechanism of Ca and Ta co-doped TiO2 ceramics

Bing CUI, Ji CHEN, Zaizhi YANG, Weiyu ZHAO, Yujun DENG, Qian YU, Juan LIU, Dong XU*   

  1. School of Materials Science and Engineering, Anhui University of Technology, Ma'anshan, Anhui 243002, China
  • Received:2020-01-14 Revised:2020-05-09 Online:2021-02-22 Published:2021-03-01

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摘要： 随着社会的飞速发展，微电子器件的功能不断向一体化方向发展，使开发具有高介电常数、低介电损耗、良好频率和温度稳定性的高介电陶瓷受到越来越多的关注。本工作通过固相反应烧结法制备了(Ca, Ta) 共掺杂的TiO2陶瓷。采用X射线衍射仪(XRD)、扫描电镜(SEM)及能谱分析仪(EDS)、阻抗分析仪、X射线光电子能谱(XPS)等对(Ca, Ta)共掺杂的TiO2陶瓷性能进行分析研究。结果表明，不同掺杂量的(Ca1/3Ta2/3)xTi1?xO2陶瓷表面形貌致密度良好，且随掺杂量增加TiO2的(110)主峰逐渐向小角度移动。当x≥7%时，(Ca1/3Ta2/3)xTi1?xO2陶瓷样品出现CaTi4O9和CaTa4O11。与纯TiO2相比，不同掺杂量的(Ca1/3Ta2/3)xTi1?xO2陶瓷皆具有巨介电常数；随掺杂量的不断增加，介电常数先升高后降低，但介电损耗变化趋势相反。当掺杂量x=3%时，(Ca1/3Ta2/3)xTi1?xO2陶瓷获得相对较优异的性能，在1 kHz下，非线性系数高达7.3，这主要是由于Ta5+掺杂使材料内部产生电子，Ca2+掺杂提高了材料内部空位的产生，产成的缺陷偶极子簇可以提高介电性能。

关键词: 巨介电, XPS分析, 共掺杂

Abstract: With the rapid development of the society, ceramic materials are being studied more and more. Recently, most of the studies on co-doping TiO2 ceramics are about trivalent acceptor and pentavalent elements which exhibit good dielectric properties, while the studies on divalent elements are relatively few. However, the mechanism, preparation process and the effects of different doped ion combinations on the dielectric properties are still unclear. Further research on the microstructure, dielectric properties and mechanism of co-doped TiO2 ceramics is of great significance. In this work, (Ca, Ta) co-doped TiO2 ceramics were prepared by a solid state reaction process. The effects of different components on their morphology, crystal structure and dielectric properties were studied. The sample with high viscosity needs to be sintered at 1400℃ for a minimum of about 4 h. When (Ca1/3Ta2/3)xTi1?xO2 ceramic with x≥7%, the second phase appeared in the (Ca1/3Ta2/3)xTi1?xO2 ceramic sample. Compared with pure TiO2, (Ca1/3Ta2/3)xTi1?xO2 ceramics all had giant dielectric constant, which roughly increased by two orders of magnitude. With the continuous increase of doping, the dielectric constant increased first and then decreased, while the dielectric loss was completely opposite. (Ca1/3Ta2/3)xTi1?xO2 ceramic with x=3% showed better dielectric and pressure-sensitive properties of ceramics. Ta doping led to the generation of electrons in the material, but Ca doping can produce vacancy and the defective dipole cluster can improve the dielectric performance.

Key words: colossal permittivity, XPS analysis, co-dop