Large electric-field induced strain in new ternary lead-free piezoelectric solid solution Na_0.5Bi_0.5TiO₃-BaTiO₃-Sr (Ta_0.5Al_0.5) O₃

Ternary lead-free piezoelectric ceramics Na0.5Bi0.5TiO3-BaTiO3-Sr(Ta0.5Al0.5)O-3 were synthesized via conventional solid-phase synthesis. All samples exhibited pure perovskite structure, indicating that Sr(Ta0.5Al0.5)O-3 can be solidified into the Na0.5Bi0.5TiO3-BaTiO3 perovskite structure. The remanent polarization P-r and coercive field E-C of the undoped Na0.5Bi0.5TiO3-BaTiO3 ceramic were P-r similar to 35.23 mu C/cm(2) and E-C similar to 42.46 kV/cm, respectively. The introduction of Sr(Ta0.5Al0.5)O-3 sharply affected the ferroelectric properties of the substrate Na0.5Bi0.5TiO3-BaTiO3 ceramics. Increase in the content of Sr(Ta0.5Al0.5)O-3 induces transition of this ternary system from a ferroelectric phase to an antiferroelectric-like phase, accompanied by double hysteresis loops in the 0.003SAT, 0.005SAT, and 0.01SAT components. The high dielectric constant epsilon' similar to 4300 was obtained for the 0.005SAT composition. The 0.015SAT composition yielded the maximum bipolar electric-field strain S (%) similar to 0.53 % and high-field piezoelectric strain coefficient d(33)*similar to 996 pm/V. This result shows that a ternary Na0.5Bi0.5TiO3-BaTiO3-Sr(Ta0.5Al0.5)O-3 solid solution is a promising alternative to lead-based piezoelectric materials in the field of high-performance actuators. (C) 2022 Elsevier B.V. All rights reserved.