Design of polymorphic heterogeneous shell in relaxor antiferroelectrics for ultrahigh capacitive energy storage
Huifen Yu, Tengfei Hu, Haoyu Wang, He Qi, Jie Wu, Ruonan Zhang, Weisan Fang, Xiaoming Shi, Zhengqian Fu, Liang Chen, Jun Chen
Abstract
Relaxor antiferroelectrics are considered promising candidate materials for achieving excellent energy storage capabilities. However, the trade-off between high recoverable energy density and high efficiency remains a major challenge in relaxor antiferroelectrics for practical applications. Herein, guided by phase-field simulation, we propose a strategy of designing polymorphic heterogeneous shell in core-shell dual-phase dielectrics to synergistically control micro and local heterostructures, resulting in comprehensive improvements in breakdown electric field, polarization fluctuation and saturation behaviors. Leveraging the core-shell effect and polarization heterogeneity, an ultrahigh recoverable energy density of 12.7 J cm-3 and an impressive efficiency of 87.2% are achieved in lead-free relaxor antiferroelectrics, making a performance breakthrough in core-shell dielectrics. This work opens up a new avenue to efficiently develop high-performance energy storage dielectrics and is expected to be popularized in other fields. The authors propose a polymorphic heterogeneous shell strategy to design core-shell dual-phase dielectrics through synergistically controlling micro and local scale heterostructures, resulting in excellent overall energy storage performance.