Enhanced energy storage in antiferroelectrics via antipolar frustration

Abstract

Dielectric-based energy storage capacitors characterized with fast charging and discharging speed and reliability^1-4 play a vital role in cutting-edge electrical and electronic equipment. In pursuit of capacitor miniaturization and integration, dielectrics must offer high energy density and efficiency⁵. Antiferroelectrics with antiparallel dipole configurations have been of significant interest for high-performance energy storage due to their negligible remanent polarization and high maximum polarization in the field-induced ferroelectric state^6-8. However, the low antiferroelectric-ferroelectric phase-transition field and accompanying large hysteresis loss deteriorate energy density and reliability. Here, guided by phase-field simulations, we propose a new strategy to frustrate antipolar ordering in antiferroelectrics by incorporating non-polar or polar components. Our experiments demonstrate that this approach effectively tunes the antiferroelectric-ferroelectric phase-transition fields and simultaneously reduces hysteresis loss. In PbZrO₃-based films, we hence realized a record high energy density among all antiferroelectrics of 189 J cm^-3 along with a high efficiency of 81% at an electric field of 5.51 MV cm^-1, which rivals the most state-of-the-art energy storage dielectrics^9-12. Atomic-scale characterization by scanning transmission electron microscopy directly revealed that the dispersed non-polar regions frustrate the long-range antipolar ordering, which contributes to the improved performance. This strategy presents new opportunities to manipulate polarization profiles and enhance energy storage performances in antiferroelectrics.