A novel lead-free NaNbO3–Bi(Zn0.5Ti0.5)O3 ceramics system for energy storage application with excellent stability

Abstract Many researches have been referred to the AFE structure of NaNbO3 in order to develop high power energy storage for NaNbO3-based ceramic. However, the square P-E loops with large Pr was observed in NaNbO3 ceramics due to the coexistence of AFE and the field-induced metastable FE, which suppress the energy storage property of NaNbO3-based ceramics. In the present work, lead-free (1-x)NaNbO3-xBi(Zn0.5Ti0.5)O3 (abbreviated as (1-x)NN-xBZT) dielectric ceramics were prepared via the traditional solid-state route. The structures, relaxor behavior and energy storage property of (1-x)NN-xBZT ceramics were investigated with the introduction of BZT. The slim P-E loops were obtained while x = 0.09–0.12 and the maximum discharge energy storage density (Wrec = 2.1 J/cm3) was obtained while x = 0.09, meanwhile a high energy storage efficiency (η = 76%) was achieved. Moreover, the charge-discharge tests show that 0.91NN-0.09BZT ceramics can achieve fast discharge rate (50 ns) and exhibit excellent stabilities of temperature and electric field, which guarantee the application prospect of 0.91NN-0.09BZT ceramics for lead-free plus power system in a wide temperature range.