Effective improved energy storage performances of Na0.5Bi0.5TiO3-based relaxor ferroelectrics ceramics by A/B-sites co-doping

Environmental-friendly relaxation ferroelectrics are anticipated as an excellent comprehensive energy storage performance materials due to their near-zero remnant polarization and slim hysteresis loop. Here, the relaxor ferroelectrics (1-x)Na0.5Bi0.5TiO3-x(Sr0.7La0.2)(Ti0.8Sn0.2)O-3 ((1-x)NBT-xSLTS) ceramics with out-standing energy storage performances are synthesized by solid-state reaction. The dielectric properties exhibit obvious frequency dispersion characteristics, and the diffusion coefficient (gamma) increases from 1.62 to 1.75 with the doping of SLTS. Also, a large polarization difference (Delta P = 20.08 mu C/cm(2)) and a high breakdown strength (E-b = 280 kV/cm) are also achieved simultaneously. As a result, a high recoverable energy density W-rec (similar to 2.52 J/cm(3)), together with a satisfactory efficiency eta (similar to 89.3%), are attained in 0.55NBT-0.45SLTS ceramic. Additionally, the corresponding samples also show satisfactory stability over the wide temperature range of 20-140 degrees C, with the variables of W-rec and eta are less than 7% and 2%, respectively. More importantly, this ceramic has an ultrashort discharge time tau(0.9) (53 ns) and a high current density J (721.86 A/cm(2)). All these results reveal that 0.55NBT-0.45SLTS ceramic is an ideal lead-free next-generation candidate material for pulsed power systems. (C) 2021 Elsevier B.V. All rights reserved.