Breakthrough energy storage in medium-entropy superparaelectrics by triple synergy strategy.

Liu, Yang; Wang, Jiarui; Liu, Lulu; Hao, Jigong; Li, Peng; Pan, Zhongbin; Wang, Jianli; Zhang, Min et al. · Nat Commun · 2026

basic_science · Level V

Where this comes from

Abstract

High-performance dielectric ceramic capacitors hold immerse potential for advanced electronics and high-power electrical systems. However, achieving both high recoverable energy density (W<sub>rec</sub>) and high energy efficiency (η) remains a critical challenge in bulk dielectric ceramics. Herein, we propose a triple-synergistic strategy that integrates medium-entropy superparaelectric design, local structural distortion, and plate-like secondary bismuth titanate phase construction in SrTiO<sub>3</sub>-based dielectric ceramics. This approach effectively promotes the formation of polymorphic polar nano-regions with short-range polar vectors, enhancing dynamic polarization response. Simultaneously, the introduction of a plate-like secondary bismuth titanate phase within the perovskite matrix significantly increases the breakdown field strength (E<sub>b</sub>) by inhibiting breakdown-path propagation. The resulting medium-entropy superparaelectric exhibits a nearly hysteresis-free P-E loop, combined with an ultrahigh E<sub>b</sub> and high polarization. Notably, the material achieves a remarkable W<sub>rec</sub> of 10.31 J/cm<sup>3</sup> along with an ultrahigh η of 90.9%. Furthermore, it demonstrates outstanding charge/discharge performance, excellent thermal stability and robust cycling stability, making it a highly promising candidate for energy storage applications. This study provides a feasible and innovative design strategy for high-performance bulk dielectrics, paving the way for the development of eco-friendly dielectric capacitors for next-generation energy storage systems.