Simultaneously high-energy storage density and responsivity in quasi-hysteresis-free Mn-doped Bi0.5Na0.5TiO₃-BaTiO₃-(Sr0.7Bi0.2□0.1)TiO₃ ergodic relaxor ceramics

High-energy storage density, responsivity and efficiency, i.e. WR = 1.07 J/cm3, ξ = 119 J/(kV m2) and η = 92%, were simultaneously obtained in Mn-doped 0.62Bi0.5Na0.5TiO3-0.06BaTiO3-0.32(Sr0.7Bi0.2□0.1)TiO3 ergodic relaxor ceramics. Appropriate Mn doping was beneficial to enhance breakdown field strength. Moreover, temperature and different atmosphere-dependent impedance spectroscopy results indicated that oxygen vacancies were the conductivity mechanism for all samples. The valence state of Mn together with the conjugation between Mn ion and oxygen vacancies was confirmed by X-ray photoelectron spectra and electric paramagnetic resonance. The above results indicate that quasi-hysteresis-free loops with high-energy storage performances can be obtained by the induced defect complex.IMPACT STATEMENTHigh-energy storage density WR = 1.07 J/cm3, responsivity ξ = 119 J/(kV m2) and efficiency η = 92% were simultaneously obtained in quasi-hysteresis-free ceramics by introducing defect complex.