Enhanced relaxation and energy storage performance in (Bi0.2Sr0.7)TiO3 modified AgNbO3 ceramics

The unique antiferroelectric behavior of AgNbO3 ceramics has great potential for energy storage applications, which have attracted increasing attention. However, the relatively low recoverable energy storage density, energy efficiency and breakdown strength of AgNbO3 ceramics severely limit their application in practice. In the present work, (Bi0.2Sr0.7)TiO3 was introduced to improve the relaxation behavior in AgNbO3 ceramics via two-step sintering, which contributed to a high breakdown strength of 580 kV/cm. A recoverable energy storage density of 7.8 J/cm3 and an energy efficiency of 56 % were obtained in 0.90AgNbO3-0.10(Bi0.2Sr0.7)TiO3 ceramics. Moreover, the benign energy storage performance could be maintained at elevated temperatures, variable frequencies and cyclings up to 105. These results demonstrate the great potential of AgNbO3-based ceramics for energy storage applications.