(Ag_0.80Bi_0.04Sr_0.04)(Nb_1-xTa_x)O₃ ceramics with enhanced energy storage for high-temperature application via synergic optimization

Dielectric capacitors with high power density are essential components in advanced electronic and micro-electronic products. Nevertheless, the limited energy storage density and efficiency, coupled with poor performance at elevated temperatures, severely restrict their usefulness. In this work, Ta was introduced to the (Ag_0.80Bi_0.04Sr_0.04)NbO₃ ceramic prepared via the hydrothermal-synthesized powders to improve the room- and high-temperature energy storage performance. A large breakdown strength of 729 kV/cm, a high recoverable energy storage density of 8.5 J/cm³ and a benign energy efficiency of 75.6% were simultaneously achieved in (Ag_0.80Bi_0.04Sr_0.04)(Nb_0.85Ta_0.15)O₃ ceramics. Moreover, the larger energy storage efficiency (83.5%) at elevated temperatures than room temperature, the benign frequency and cycle stability foreshow great potential in realizing the application of capacitors at high-temperatures.