Enhanced piezoelectric performance and depolarization temperature in BiFeO3‒BaTiO3 piezoelectric ceramics

Abstract

In recent years, bismuth ferrite-based (BiFeO₃‒BaTiO₃) lead-free piezoelectric ceramics have garnered extensive research attention. This is attributed to their high Curie temperature, rendering them promising candidates for high-temperature piezoelectric device applications. Nevertheless, attaining synergistic piezoelectric performance within BiFeO₃‒BaTiO₃ ceramics remains a formidable challenge. In this study, BiGaO₃ was incorporated into the BiFeO₃‒BaTiO₃ matrix. A systematic investigation and discussion were carried out regarding the phase structures, microstructures, ferroelectric properties, piezoelectric properties, and dielectric properties of the fabricated materials. The synthesized ceramics were deliberately engineered to establish a rhombohedral and pseudo-cubic phase boundary, which serves as a fundamental prerequisite for enhancing piezoelectric properties. Due to the synergistic impacts of appropriate BiGaO₃ doping, the 0.69BFG_0.025‒0.31BT ceramics achieved favorable piezoelectric performance characteristics, including a piezoelectric coefficient (d₃₃) of 254 pC/N, a Curie temperature of 472°C, and a high depolarization temperature of 545°C. These results affirm that this material holds great potential for applications in high-temperature piezoelectric devices.