Enhanced energy storage in high-entropy superparaelectrics via local ferroelectric polarization.

Wei, Tongxin; Zou, Jinzhu; Song, Miao; Zhu, Kai; Yan, Zhongna; Zhou, Zhifang; Zhou, Xuefan; Zhou, Kechao et al. · Nat Commun · 2026

basic_science · Level V

Where this comes from

Abstract

Dielectric ceramic capacitors with ultrahigh power density have become essential in modern power electronics. Guided by phase-field simulations and experiments, we propose a "local ferroelectric-global superparaelectric" strategy. This approach enhances P<sub>m</sub> by introducing local ferroelectric polarization within a superparaelectric matrix, enabling superior energy storage performance. Introducing strong ferroelectric PbTiO₃ into a (Bi<sub>0.2</sub>Na<sub>0.2</sub>K<sub>0.2</sub>La<sub>0.2</sub>Sr<sub>0.2</sub>)Ti<sub>0.9</sub>Zr<sub>0.1</sub>O<sub>3</sub> high-entropy superparaelectric achieves an ultrahigh energy storage density of ~21 J/cm³ with an efficiency of ~87% at 110 kV/mm. Multiscale structural characterization and theoretical calculations reveal the atomic-scale mechanism for this performance enhancement. At ≤ 30% PbTiO<sub>3</sub>, the Pb<sup>2+</sup> lone pair effect is locally confined, boosting local ferroelectric distortion while maintaining a superparaelectric average structure for superior energy storage. At 40-50%, this effect extends throughout the matrix, inducing submicro-scale domains and macroscopic piezoelectricity. This work presents a design and material system for high-performance energy storage ceramics, laying the theoretical foundation for advanced high-entropy ferroelectric applications.