IMF2017

Ferro-/piezoelectric materials which can function at high temperatures and high electric fields are highly desired for transducers, sensor and actuators. The current high-performance lead-based materials like PMN-PT are not suitable for many of those applications due to their relatively low Curie temperatures (T_C < 160 °C) and low coercive fields (E_C < 5 kV/cm). Additionally, their high lead content presents a big concern due to lead toxicity to human health and environment. In this work, a novel lead-reduced binary solid solution system xBi(Zn_2/3Ta_1/3)O₃-(1-x)PbTiO₃ (x = 0 to 1) was synthesized by solid state reaction method and systematically characterized in terms of crystal structure and electrical properties by various techniques. Powder X-ray diffraction indicated the formation of a solid solution with x = 0 to 0.27, which crystallize in a tetragonal phase symmetry of perovskite structure. A very high tetragonality (a/c > 1.06) was observed in this system indicating a large crystal distortion and high polarization. Dielectric measurements showed that the solid solution has high Curie temperatures (T_C > 400°C). Ferroelectric characterization indicated a high coercive field (E_C > 20 kV /cm) for this system. The materials also exhibit good piezoelectric properties. These electrical properties were explained from the crystal chemistry aspects. The high-TC and high-EC features signify that the Bi(Zn_2/3Ta_1/3)O₃-PbTiO₃ system is a promising and more environmental friendly candidate for electromechanical transductions applications that can operate in a wider temperature range and higher electric field range.