Constructing novel binary Bi0.5Na0.5TiO3-based composite ceramics for excellent energy storage performances via defect engineering

With the rapid development of sustainable and renewable technologies, electrostatic capacitors are now becoming a promising energy storage device. However, simultaneous achievement of large polarization and breakdown electric field of the electrostatic capacitors are an important technical challenge for improving energy storage density. In this article, we propose a surrogate approach by A-site defect engineering in (Bi0.47Sm0.03Na0.5-x)(0.94)Ba0.06TiO3 (BSNBT-x) ceramics to form two-phase structured composites ceramics, which contains of perovskite structured of the Bi0.5Na0.5TiO3 (BNT) with large polarization and Aurivillius phases of BaBi4Ti4O15 (BBT) generation high breakdown electric field. The phase-field simulations further demonstrate the Aurivillius phases BBT could significantly enhance breakdown electric field and retain high polarization. Accordingly, excellent recoverable energy density (W-rec similar to 4.62 J/cm(3)) and discharged efficiency (eta similar to 79.1%) are achieved in (Bi0.47Sm0.03Na0.42)(0.94)Ba0.06TiO3 ceramics. Moreover, the corresponding ceramic also displays brilliant thermal endurance (20 degrees C to 220 degrees C), fatigue endurance (similar to 10(6) cycles), and frequency stability (1 Hz to 1000 Hz). These results could provide a general strategy to develop the energy-storage performances of ceramic capacitors for application in high-energy/power-density storage systems.

Automated summary

This article introduces a method to improve the energy storage density of electrostatic capacitors by adjusting the structure of ceramics to achieve large polarization and high breakdown electric field. The experimental results show that excellent energy density, discharge efficiency, thermal endurance, fatigue endurance, and frequency stability can be achieved using this method.