Liqiang He, Le Zhang, Yating Ran, Cunle Bo, Kaiyun Chen, Yao Liu, Chen Zhang, Zihao Zheng, Jinming Guo, Danyang Wang, Danyang Wang, Shujun Zhang, Sen Yang, Xiaobing Ren, Zibin Chen, Dong Wang, Dong Wang
A critical challenge for the application of lead-free antiferroelectrics in energy storage systems is their poor thermal stability and low efficiency when the superior energy storage density is attained, primarily due to the inherent first-order nature and narrow temperature window of antiferroelectric-to-ferroelectric transitions. Here, we elucidate a unique percolating interaction between antipolar regions in antiferroelectrics and engineered defect pairs using density functional theory and phase field calculations. Strategic distribution of the strongly coupled Li-Ta pairs in AgNbO3 fosters a percolating interaction that facilitates antipolar rotations, enabling a pronounced polarization change with minimal hysteresis. Guided by theoretical calculations, a large recoverable energy storage density of 12.8 J/cm3, with a high efficiency of 90%, is achieved at room temperature in Ag0.95Li0.05Nb0.35Ta0.65O3 ceramics. Moreover, the superior energy storage performance can remain stable within a wide temperature range from −70 to 170 °C, which paves the way for application in advanced energy capacitors. A percolating interaction between antipolar regions and engineered defect pairs facilitates antipolar rotations, enabling superior energy storage performance in AgNbO3-based ceramics.