Phase transition behavior, dielectric and ferroelectric properties of (1 - x)(Bi_0.5Na_0.5)TiO₃-xBa_0.85Ca_0.15Ti_0.9Zr_0.1O₃ ceramics

(1 - x)(Bi_0.5Na_0.5)TiO₃-xBa_0.85Ca_0.15Ti_0.9Zr_0.1O₃ ceramics were prepared by solid state route and their phase structure and electric properties were investigated with the focus on optimizing properties for capacitor applications. There are two obvious maxima in the permittivity curves for x = 0.1-0.4 compositions. The first anomaly is suggested to be due to thermal evolution of LT-PNRs and the second one is attributed to the phase transition between the two types PNRs and the thermal evolution of HT-PNRs. The x = 0.3 sample has an operational temperature range from 87 °C to 310 °C. Most of the samples exhibit a dielectric thermal hysteresis. The x = 0.2-0.4 compositions exhibit a significant pinched P-E hysteresis loops. A large d₃₃* of 427 pm/V was observed in 0.7BNT-0.3BCTZ composition. The x = 0.5-0.6 samples show a slim P-E hysteresis loop, and the sample with x = 0.5 exhibits high energy density of 0.6649 J/cm³ and energy storage efficiency of 83.17%, making it most suitable for application as high energy density capacitors.