Regulating local electric field to optimize the energy storage performance of antiferroelectric ceramics via a composite strategy

Electrostatic energy storage technology based on dielectrics is the basis of advanced electronics and high-power electrical systems. High polarization (P) and high electric breakdown strength (E_b) are the key parameters for dielectric materials to achieve superior energy storage performance. In this work, a composite strategy based on antiferroelectric dielectrics (AFEs) has been proposed to improve the energy storage performance. Here, AlN is selected as the second phase for the (Pb_0.915Ba_0.04La_0.03)(Zr_0.65Sn_0.3Ti_0.05)O₃ (PBLZST) AFEs, which is embedded in the grain boundaries to construct insulating networks and regulate the local electric field, improving the E_b. Meanwhile, it is emphasized that AFEs have the AFE–FE and FE–AFE phase transitions, and the increase of the phase transition electric fields can further improve the recoverable energy density (W_rec). As a result, the E_b increases from 180 to 290 kV·cm⁻¹ with a simultaneous increase of the phase transition electric fields, magnifying the W_rec to ~144% of the pristine PBLZST. The mechanism for enhanced E_b and the phase transition electric fields is revealed by the finite element simulation method. Moreover, the PBLZST:1.0 wt% AlN composite ceramics exhibit favorable temperature stability, frequency stability, and charge–discharge ability, making the composite ceramics a promising candidate for energy storage applications.