Structurally Regulated Design Strategy of Bi 0.5 Na 0.5 TiO 3 -Based Ceramics for High Energy-Storage Performance at a Low Electric Field.

Dielectric ceramic capacitors are prospective energy-storage devices for pulsed-power systems owing to their ultrafast charge-discharge speed. However, low energy-storage density makes them difficult to commercialize for high-pulse-power technology applications. Herein, we presented a structurally regulated design strategy to disrupt a long-range ferroelectric order, refined grains, and eventually achieve excellent comprehensive energy-storage performance in (1 - x ) (0.7Bi 0.5 Na 0.5 TiO 3 -0.3SrTiO 3 )- x Sm(Zn 2/3 Nb 1/3 )O 3 eco-friendly ceramics. A large W rec of ∼7.43 ± 0.05 J/cm 3 and a high η of ∼85 ± 0.5% of 0.96 (0.7Bi 0.5 Na 0.5 TiO 3 -0.3SrTiO 3 )-0.04 Sm(Zn 2/3 Nb 1/3 )O 3 were obtained at a low electric field of 290 kV cm -1 with good energy-storage temperature (25-120 °C), frequency (1-100 Hz) stability, and charge-discharge properties ( P D ∼ 74 ± 1 MW/cm 3 and τ 0.9 ∼ 159 ± 2 ns). This strategy inspires rational structurally regulated designs and aims to promote the development of eco-friendly 0.7Bi 0.5 Na 0.5 TiO 3 -based ceramics with excellent energy-storage characteristics.