A study of the structure and dielectric properties for high-valence compensation of Bi3+ ion-doped Ba(FeTa)(0.5)O-3 ceramics

作者：Chai Yin Lai; His Chi Shiung; Lin You Ting; Chang Yee Shin^*

来源：Journal of Alloys and Compounds, 2014, 588: 248-253.

DOI：10.1016/j.jallcom.2013.11.022

• Dielectric materials
• Relaxor
• Valence compensation
• Doped
• BFT

The higher valence compensation of the Ba1-xBix(FeTa)(0.5)O-3 (x = 0-0.1) system is obtained via a solid-state reaction. The characteristics, including phase formation, microstructure and dielectric properties, are also investigated. In the complex perovskite oxides Ba1-xBix(FeTa)(0.5)O-3 system, the dielectric constant increases when the Bi3+ ion concentration increases, because there is an increase in valence compensation dipoles. The dielectric constant Ba0.94Bi0.06(FeTa)(0.5)O-3 ceramics sintered at 1250 degrees C are about 8 x 10(4)-10(5), with a low dissipation factor at temperatures between 273 and 458 K and a frequency of 1 kHz. The temperature-dependent dielectric constant and loss curves, measured in the temperature range, 273-458 K, and at a frequency of 1 kHz, indicate that the samples exhibit typical relaxor behavior over a broad temperature range. Complex impedance spectroscopy shows the presence of barrier layers in bi-phase ceramics, which indicates that the orientation and space charge polarization are dominant for Ba1-xBix(FeTa)(0.5)O-3 dielectric behavior. The frequency dependence of the dielectric loss peak obeys an Arrhenius law, with an activation energy of 0.24 eV, and the relaxation time is 10(-9) s.

• 出版日期2014-3-5