Structural and dielectric properties of (1-x)(Sr0.7Pb0.15Bi0.1)TiO3-x(Bi0.5Na0.5)TiO3 energy storage ceramic capacitors

Abstract In this study, (1-x)(Sr0.7Pb0.15Bi0.1)TiO3-x(Bi0.5Na0.5)TiO3 ((1-x)SPBT-xBNT, x = 0–0.5) ceramics are prepared by solid-state reaction method, aiming to investigate the influence of BNT doping on SPBT ceramics in structure and properties. SEM and EDS show a secondary phase of lead bismuth titanium oxide (PBT) forms by doping BNT into SPBT. The doping of BNT transforms the polar nano regions into macrodomain in SPBT demonstrated by TEM images, and makes the polarization reversal of SPBT-based ceramics more difficult at high frequencies, leading to the increasing frequency dependence of dielectric constant. The temperature stability in high-temperature range has improved. The maximum polarization increases gradually, and the 0.5SPBT-0.5BNT begins to show a slight double hysteresis loop. The breakdown strength of 0.7SPBT-0.3BNT ceramics reaches 18.7 kV/mm.