Dielectric Permittivity and Electric Modulus in Bi₂Ti₄O₁₁

Authors

Jianjun Liu, University of Nebraska at Omaha
Chun-Gang Duan, University of Nebraska at OmahaFollow
Wai-Ning Mei, University of Nebraska at OmahaFollow
R. W. Smith, University of Nebraska at OmahaFollow
John R. Hardy, University of Nebraska-LincolnFollow

Date of this Version

8-2003

Comments

Published in J. Chem. Phys., Vol. 119, No. 5, 1 August 2003. Copyright © 2003 American Institute of Physics. Used by permission.

Abstract

Frequency and temperature dependences of dielectric permittivity and electric modulus of pure and Ba-doped Bi₂Ti₄O₁₁ were studied in the ranges of 10^-1–10⁶ Hz and -150–350 °C, respectively. We found that the antiferroelectric phase transition temperature of Bi₂Ti₄O₁₁ decreases with Ba doping. In the permittivity studies, we also observed dielectric relaxation peaks shift to higher temperature with increasing frequency. Furthermore, in the electric modulus formalism, conducting peaks were uncovered above 150 °C in addition to the dielectric relaxation peak. We discussed the mechanisms for the dielectric relaxation and conduction processes based on TiO₆ octahedra distortion and a space-charge model.