Novel barium titanate based ferroelectric relaxor ceramics with superior charge-discharge performance

Lead-free 0.9BaTiO3-0.1(Bi0.9Na0.1)(In0.8Zr0.2)O3 (0.9BT-0.1BNIZ) ferroelectric relaxor ceramic was synthesized by solid-state reaction method. A dense microstructure and fine grain size was obtained with addition of BNIZ content. The dielectric behaviors indicated the dominance of ergodic relaxor phase. The 0.9BT-0.1BNIZ ceramic was found to possess an enhanced recoverable energy density (WR∼1.33 J/cm3) and efficiency (η∼88%) under 18 kV/mm at room temperature. What's more, WR is maintained ≥0.53 J/cm3 with η ≥ 94% under 10 kV/mm and the variation of WR is less than 15% over 25∼140 °C. The high stability of energy storage properties is mainly ascribed to the characteristics of ergodic relaxor phase. The stored energy was released in sub-microseconds (∼0.19 μs). The superior current density (CD∼796 A/cm2) and the power density (PD∼39.8 MW/cm3) were obtained simultaneously. The enhanced WR and the superior charge-discharge performances strongly demonstrate that the BT-based ceramics are promising candidates of high-power pulse capacitor applications.