LAUSR

Abstract BiFeO3-BaTiO3 (BFBT) is a promising high temperature piezoelectric ceramic system, as it possesses both high electromechanical properties and high Curie temperature. However, pure BFBT commonly exhibits large electrical conductivity at high temperatures, and there is considerable disagreement on its electrical conduction mechanism. Here we investigated the electrical conduction mechanisms of 0.70BiFeO3-0.30BaTiO3 and 0.67BiFeO3-0.33BaTiO3 ceramics by systematic impedance spectroscopy measurements as a function of oxygen partial pressure and temperature. Both ceramics exhibit higher electrical conductivity with an increase of oxygen partial pressure, consistent with p-type semiconductor behaviors. Particularly, reduced conductivity and improved ferroelectric remanent polarization can be obtained in BFBT when annealed in inert atmosphere. This study provides fundamental basis for preparing insulating and high performance BFBT ceramics.