Excellent Energy Storage Performance of Perovskite High-Entropy Oxide-Modified (Bi 0.5 Na 0.5 )TiO 3 -Based Ceramics

作者：Xue Zhang, Fan Zhang, Yiwen Niu, Zhiqiang Zhang, Xueqiong Lei, Zhan Jie Wang · 发表于：ACS Applied Electronic Materials · 年份：2024 · DOI：10.1021/acsaelm.4c00679 · 被引用次数：35 · 研究领域：Ferroelectric and Piezoelectric Materials、Dielectric properties of ceramics、Multiferroics and related materials

Due to the typical dielectric relaxation behavior of perovskite high-entropy ceramics (HECs), high-entropy engineering is beneficial for improving energy storage performance and has drawn extensive concern. In this study, high-entropy oxide (Bi 0.2 Na 0.2 Ba 0.2 Sr 0.2 Ca 0.2 )(Ti 0.9 Nb 0.1 )O 3 (BNCBSTN)-modified 0.45(Bi 0.5 Na 0.5 )TiO 3 -0.55(Sr 0.7 Bi 0.2 )TiO 3 (BNT-SBT) systems, BNT-SBT- x BNCBSTN (0 ≤ x ≤ 0.5) ceramics, were designed and prepared using a hydrothermal method. It is found that the introduction of BNCBSTN into BNT-SBT promotes the configuration entropy and induces strong dielectric relaxation behavior, thereby greatly improving the energy storage performance. In addition, grain refinement, increased resistivity, and widened band gap are achieved by the modification of BNCBSTN, leading to a significant enhancement of the breakdown electric field ( E b ). Consequently, BNT-SBT-0.3BNCBSTN HEC exhibits a preeminent recoverable energy density ( W rec = 6.04 J/cm 3 ) and energy storage efficiency (η = 85%) under an excellent E b of 410 kV/cm as well as good temperature and frequency stability. The remarkable improvement in energy storage performance indicates that modifying the ferroelectric system with high-entropy oxide is a feasible approach for developing energy storage capacitors.