Electrical properties of 0.94Bi_0.5Na_0.5TiO₃–0.06Ba(Zr_0.055Ti_0.945)O₃ lead-free ceramics with high thermal stability

Here we report the 0.94(Bi_0.5Na_0.5)TiO₃–0.06Ba(Zr_0.055Ti_0.945)O₃ (0.94BNT–0.06BZT) lead-free ceramics was synthesized by two-step solid state reaction route. The structural, dielectric, ferroelectric, piezoelectric and electromechanical properties of the ceramics were studied, and showed excellent electric properties (P _s  = 39.9 μC/cm², P _r  = 33.7 μC/cm², E _c  = 2.79 kV/mm, S = 0.20%, d ₃₃  = 174 pC/N, k _p = 0.33). The depolarization temperature (T _d ) of the ceramics is about 65 °C, which is determined from the first hump of relative dielectric constant. The electromechanical factor k _p disappears at 65 °C, is consistent with the depolarization temperature (T _d ) and the ferroelectric-antiferroelectric phase transition temperature (T _fe−afe ) determined from the temperature-dependent P–E and bipolar S–E curves. These results indicate the 0.94BNT–0.06BZT ceramics has a good thermal stability in range of − 60–60 °C, and meets the actual demand.