High Energy Storage Characteristics of (0.5–x)BiFeO₃-0.5 Bi_0.5Na_0.5TiO₃-xBaTiO₃ Ternary Lead-Free Ferroelectric Ceramics under Low Electric Field

(0.5– x )BiFeO 3 -0.5 Bi 0.5 Na 0.5 TiO 3 - x BaTiO 3 ( x = 0.12, 0.14, 0.16, 0.18, 0.20, 0.22, 0.24, and 0.28) ferroelectric ceramics were synthesized using traditional solid-state reaction methods. The elongated P–E hysteresis loops revealed that the ternary system had good energy storage characteristics. A high recoverable energy storage density ( W rec ) of 2.1 J/cm 3 and a moderate energy storage efficiency of η ∼ 67% were achieved simultaneously for the x = 0.12 composition under a lower electric field of 140 kV/cm. Furthermore, the x = 0.12 composition exhibited good stability in a wide temperature (25–125 °C) and frequency range (0.1–10 2 Hz) and good fatigue resistance in cycling frequency (1–10 3 ). Furthermore, the ceramic also exhibited considerable charging–discharging performance with a fast discharging rate ( t 90 < 0.05 μs), a moderate current density (158 A/cm 2 ), and a moderate power density (4.738 MW/cm 3 ). Overall, 0.38BiFeO 3 -0.5Bi 0.5 Na 0.5 TiO 3 -0.12BaTiO 3 ceramics are considered a lead-free competitive candidate for the development of high energy storage capacitors.