Boosting capacitive energy storage performance of bismuth sodium titanate-based lead-free ceramics under low electric field

作者：Fei Yan, Xin Qi, Jin Qian, Simin Wang, Cheng Shi, Zixiong Sun, Weiwei Wang, Ke Cao · 发表于：Chemical Engineering Journal · 年份：2025 · DOI：10.1016/j.cej.2025.164247 · 被引用次数：23 · 研究领域：Ferroelectric and Piezoelectric Materials、Microwave Dielectric Ceramics Synthesis、Dielectric properties of ceramics

Dielectric capacitors have attracted significant research attention in advanced pulsed power systems, owing to their unique advantages like ultrahigh power density and rapid charge–discharge capabilities. However, prevailing research strategies predominantly pursue enhanced energy storage through elevated electric fields, while often neglecting performance under practical low-field conditions. To address this issue, KNbO 3 was incorporated into Bi 0.5 Na 0.5 TiO 3 (BNT) lead-free ceramics to disrupt the long-range ferroelectric order and refine the grain size, while Bi 3+ was utilized to regular polarization in this study. Notably, the engineered BNT-based ceramics, synthesized using a conventional solid-state reaction, achieved a recoverable energy storage density of 2.31 J cm −3 and a power density of 68.66 MW cm −3 under a low applied electric field of 140 kV cm −1 . This represents an enhancement exceeding 500 % in recoverable energy storage density and 700 % improvement in energy storage efficiency versus pure BNT ceramics. Moreover, both energy storage density and efficiency exhibited excellent thermal stability over a temperature range of 30–180 °C, frequency stability from 1 to 100 Hz, and cycle stability up to 10 5 cycles. This study presents a promising strategy for developing BNT-based lead-free ceramics with superior energy storage properties under low electric field conditions.