High piezoelectricity with broad temperature insensitivity in BiScO3-PbTiO3-based piezoceramics

The surge of interest in searching for high-temperature piezoceramics has proved that BiScO3-PbTiO3 ceramics with high piezoelectric constant and high Curie temperature are promising for high-temperature nondestructive inspection (NDT) applications. However, their inferior temperature stability limits the applications. In this paper, 0.365BiScO(3)-0.635(Pb1-3x/2Bix)(Ti0.99Zn0.01)O-3 (BS-xBPZnT) system has been investigated by doping Bi ions to A-site and Zn ions to B-site based on the lattice distortion and hybrid orbital theory. The transformation of domain structures has been achieved, which is varied from typical strip-like domains to complex configuration of micro-domain. Meanwhile, the morphotropic phase boundary (MPB) was constructed in this system. The results indicated that x = 0.01 composition can reach high piezoelectric coefficient (d(33)) of 490 pC/N and high Curie temperature of 428 degrees C. Besides, the in situ high-temperature d(33) results show that x = 0.01 sample can keep stable from 50 degrees C to 350 degrees C, and its depolarization temperature is 410 degrees C. The in situ high-temperature XRD and PFM results show that the temperature stability of phase structure and domain structure is the key factor to improve the stabilization of d(33). This work confirms that BS-xBPZnT ceramics have superior potential for high-temperature application, paving a significant step toward enhancing the thermal stability of high-temperature piezoceramics.