Outstanding energy storage properties and dielectric temperature reliability in Na0.35Bi0.35Sr0.3TiO3-based relaxor ferroelectrics through entropy engineering

It is challenging to realize excellent overall properties of relaxor ferroelectrics to overcome the demands of capacitors. In this research, an effective strategy of entropy engineering addresses the above problem. The (1-x)Na_0.35Bi_0.35Sr_0.3TiO₃-xCa_0.85Sm_0.1(Mg_1/3Nb_2/3)O₃ (NBST-xCSMN) ceramics were prepared via a solid-phase reaction method. The linear dielectric CSMN was adopted as additive to adjust the configuration entropy (∆S_config) of samples. The outcomes indicate that the enhancement of ∆S_config is beneficial to reduce grain size and interfacial polarization, improve activation energy and optimize dielectric features. The superior energy storage capability (W_rec = 5.2 J/cm³, η = 88 %) as well as dielectric temperature reliability (∆C/C_25°C ≤ ± 15 %, −57–323 °C) in accordance with X9R was gained in NBST-0.15CSMN with ∆S_config = 1.91R. This study indicates that entropy engineering is a shortcut to design next-generation capacitors with high comprehensive performance.