Electrical properties of zirconium-modified BiScO₃-PbTiO₃ piezoelectric ceramics at re-designed phase boundary

Bismuth-based perovskite solid solutions 0.36Bi(Sc_1−xZr_x)O₃-0.64PbTiO₃ (BSPT) were designed to obtain morphotropic phase boundary (MPB) between phase tetragonal (T) and rhombohedral (R) to enhance the piezoelectric properties. Their phase structures were investigated by the X-ray diffraction, temperature dependence of dielectric constant. The morphotropic phase boundary separate the rhombohedral and tetragonal phases for the 0.36Bi(Sc_1−xZr_x)O₃-0.64PbTiO₃ system at x = 0.01. The piezoelectric coefficient d₃₃ for the ceramics at x = 0.01 is 559 pC/N at 250 °C and 270 pC/N at −100 °C, which is higher than that of traditional piezoelectric materials. Moreover, zirconium doping of 0.36BiScO₃-0.64PbTiO₃ decreased the coercive field (E_c), dielectric dissipation factor tanδ, and electromechanical coupling factor k_p. Effect of zirconium doping on piezoelectric and electromechanical properties are reported and discussed as a function of temperature. This study indicated the BSPT material at redesigned MPB is a promising candidate for wide temperature range sensor applications.