Excellent energy storage properties in non-stoichiometric Bi0.5Na0.5TiO3-based relaxor ferroelectric ceramics

The rapid development of high-power and pulsed-power techniques inspires extensive investigates on high-performance ceramic-based capacitors. However, the low recoverable energy density (Wrec) hampers their wider applications. Herein, the non-stoichiometric Bi0.5Na0.5TiO3-based ceramics were designed and studied. The proper introduction of oxygen vacancies facilitated activating defect dipole, giving rise to reduced remanent polarization. Consequently, the optimal composition exhibited an exceptional high Wrec of 8.3 J/cm3, a high efficiency of 85%, and excellent anti-fatigue and thermal reliability. This work provides an efficient approach to explore ceramic capacitors with high capacitive energy storage performances.