Structure and enhanced electrical properties of high-temperature BiFeO3-PbTiO3-BaZrO3 ceramics with bismuth excess

Abstract 0.54BiFeO 3 –0.36PbTiO 3 –0.1BaZrO 3 (BF-PT-BZ) ceramics with various amounts of excess Bi were fabricated by conventional solid-state method and the microstructure and electrical properties were researched to estimate the role of excess Bi on the structure and properties in sintering process. XRD results indicate that tetragonal distortion declined monotonously with the increasing amount of Bi. SEM images reflect that the grain size was enlarged by excess Bi addition. The dielectric, ferroelectric and piezoelectric properties of BF-PT-BZ ceramics were improved effectively. Remnant polarization P r , piezoelectric coefficient d 33 and planar mode electromechanical coupling factor k p of BF-PT-BZ ceramics with 1 mol% Bi excess are 20 μC/cm 2 , 197 pC/N and 0.448, improved by 20%, 30% and 39%, respectively. The temperature of the maximum dielectric constant T m of 445 °C for BF-PT-BZ-1 mol% Bi shows tremendous potential for high temperature piezoelectric applications.