Enhanced energy storage performances of (Sr0.7Bi0.2)TiO3 ceramics through highly polarized Ba ions

Abstract

The goal of searching for advanced dielectrics with high energy storage properties (ESPTs) is still challenging. Here, novel (Sr 0.7−x Ba x Bi 0.2 )TiO 3 (x = 0–0.10) ceramics were designed to optimize dielectric breakdown and ESPTs to meet the needs of high storing energy. The dielectric behavior, energy storage properties, thermal stability, fatigue endurance, and discharging behavior of the studied ceramics were intensively explored. By replacing Sr 2+ with highly polarized Ba 2+ , lattice distortion is induced to produce relaxation characteristics, which improves the maximum polarization and dielectric breakdown strength of the (Sr 0.7−x Ba x Bi 0.2 )TiO 3 ceramics. The optimal ESPTs can be obtained in the (Sr 0.66 Ba 0.04 Bi 0.2 )TiO 3 ceramic with a charge energy density of 1.97 J/cm 3 and an efficiency of 86.8% under 290 kV/cm, respectively. Simultaneously, it also shows excellent thermal stability in temperature from 30 °C to 160 °C, good fatigue behavior up to 10 5 cycles, and a fast discharging speed of 1.8 μ s, indicating potential high-performance applications. • Highly polarized Ba 2+ was designed to tailor ferroelectric polarization and dielectric breakdown. • Dielectric breakdown dominates the enhancement of energy performances. • Relaxor behavior contributes to thermal stability and fatigue endurance. • A high energy density of 1.97 J/cm 3 is obtained in (Sr 0.66 Ba 0.04 Bi 0.2 )TiO 3 .