Dielectric energy storage devices with high power density show great potential in applications of smart grids, electrical vehicles, pulsed power weapons, and so on. However, their limited recoverable energy density badly restricts their utilization and harms the miniaturization, portability, and integration of electronics. Herein, equivalent amounts of Bi2O3 and Sc2O3 were introduced to improve the energy storage property of 0.10 wt % MnO2-doped AgNbO3@SiO2 ceramics by simultaneously enhancing the maximum polarization, breakdown strength, and relaxation feature. It is particularly interesting that the AgNbO3-based ceramics with 4 mol % Bi2O3 and Sc2O3 demonstrate the recoverable energy storage density of 5.9 J/cm3 with the energy storage efficiency of 71%, exhibiting 1.9 and 1.4 times enhancement compared to 0.10 wt % MnO2-doped AgNbO3@SiO2 ceramics. In addition, the benign energy storage performance can be maintained at elevated temperatures and frequencies and up to 105 cycling, indicating great potential in advanced high-power applications.
Keywords: A/B-site substitutions; AgNbO3; antiferroelectric; core−shell; dielectric energy storage ceramics.