Structural, Dielectric and Leakage Current Behaviors of Ti-Substituted BiFeO₃ Ceramics

Abstract

The microstructure, dielectric and leakage current characteristics of Bi(Fe_1-x Ti _x )O₃ (x = 0–0.2) polycrystalline ceramics have been investigated. Phase transformation from rhombohedral to orthorhombic symmetry occurs at around x∼0.2. Average grain size decreases rapidly and then saturates with the size of few μm above x = 0.025. The steplike decrease in ϵ for the composition of x = 0 and 0.01 are related dielectric relaxation. Leakage currents were much decreased by about 6 orders of magnitude above x = 0.025. Similarly to the results of SEM images and dielectric constants, leakage currents were changed with Ti substitution.

Keywords:

• Multiferroics
• BiFeO₃
• hysteresis
• leakage current

Acknowledgment

This study was financially supported by Pukyong National University in the 2009 Post-Doc. Program and supported by the Korean Research Foundation Grant funded by the Korean Government (MOEHRD, Basic Research Promotion Fund) (KRF-2007-412-J00901).