Improved energy storage performance achieved in (Bi0.5Na0.5)TiO3-based relaxor ferroelectrics via composition engineering

The utilization of relaxor-ferroelectrics is considered to become a feasible scheme to achieve high energy storage performance owing to their high polarization and low hysteresis loss. Herein, the (1-x)(Bi0.5Na0.5)TiO3-x(Sr0.7La0.2)(Ti0.9Zr0.1)O3 ((1-x)BNT-xSLTZ) ceramics were synthesized by using the traditional solid-state reaction method. A favorable recoverable energy density (Wrec) of 4.0 J cm−3 could be obtained at 295 kV cm−1 by combining composition-driven intensive relaxation behaviors and fine grains. Further, the high stabilities for temperature and frequency, with energy density of 1.56–1.41 J cm−3 over a range of 25–150 °C at 150 kV cm−1 and energy density of 1.48–1.67 J cm−3 at 150 kV cm−1 ranging from 1 Hz to 200 Hz, are achieved in 0.6BNT-0.4SLTZ. These results suggest that the BNT-SLTZ relaxor ferroelectric ceramics have capacity of becoming a promising candidate for high-power energy storage applications.