Preparation and characterization of high Curie-temperature piezoelectric ceramics in a new Bi-based perovskite of (1 − x)PbTiO3-xBi(Zn1/2Hf1/2)O3

Abstract

To meet the increasing demand for high temperature piezoelectric actuator and transducer applications, much attention has been paid on exploring piezoelectric materials which can work efficiently under high temperature conditions. In the present study, a new Bi-based perovskite (ABO₃) of (1 − x)PbTiO₃-xBi(Zn_1/2Hf_1/2)O₃ has been investigated. For the compositions of x < 0.20, it is interesting to observe that the tetragonality (c/a) remains relatively constant over the entire tetragonal phase. This unusual phenomenon is in contrast to the behavior of most PbTiO₃-based solid solutions, wherein the c/a is usually reduced. As a result, the Curie temperature (T_C) increases from 490 °C for pure PbTiO₃, to as high as 528 °C for x = 0.10, indicating the present PbTiO₃-Bi(Zn_1/2Hf_1/2)O₃ to be a high-T_C piezoelectric material. It is proposed that the maintained large tetragonality and high T_C could be attributed to the large spontaneous polarization (P_S) displacements induced by the strong Pb/Bi-O hybridization and coupling interactions between Pb/Bi and B-site ferroelectric-active cations.