Impedance spectroscopy study of polycrystalline Bi6Fe2Ti3O18

[摘要] The electrical properties of polycrystalline Bi₆Fe₂Ti₃O₁₈ are investigated by impedance spectroscopy in the temperature range 30â€�??550°C. The imaginary part of impedance as a function of frequency shows Debye like relaxation. Impedance data are presented in the Nyquist plot which is used to identify an equivalent circuit and the fundamental circuit parameters are determined at different temperatures. The grain and grain-boundary contributions are estimated. The results of bulk a.c. conductivity as a function of temperature and frequency are presented. The activation energies for the a.c. conductivity are calculated. The polaron hopping frequencies are estimated from the a.c. conductivity data.

[学科分类] 材料工程

[关键词] BLSF;equivalent circuit;ferroelectric;impedance;polaron hopping.