Enhanced dielectric energy storage properties of PLZST relaxor-antiferroelectric ceramics achieved via phase transition modulation and processing optimization

https://doi.org/10.1016/j.ceramint.2025.03.189

Antiferroelectric (AFE) ceramic materials, especially those based on lead zirconate (PZ) materials, are renowned for their outstanding energy storage properties, which stem from their unique field-induced phase transitions. These features make them excellent candidates for high-power pulse capacitor applications. However, PZ-based antiferroelectric materials currently suffer significant challenges, including low energy storage density and the inability to simultaneously enhance energy storage efficiency, which greatly impedes their practical application. To address these challenges, this study optimizes both the phase transition and electric breakdown fields, ultimately developing a relaxation antiferroelectric system that facilitates the collaborative improvement of energy storage characteristics. Specifically, Sr²⁺ doped Pb_0.98La_0.02[(Zr_0.5Sn_0.5)_0.88Ti_0.12]_0.995O₃ ceramics were fabricated using the conventional solid-state reaction. The incorporation of Sr²⁺ effectively disrupts the antiparallel polar order of the antiferroelectric phase, thereby stabilizing it. It reduces the potential barrier for phase transition switching and improves the breakdown electric field, thus simultaneously enhancing recoverable energy density and efficiency. The efficiency peaked at 90 % when x = 0.06. Building on this, a viscous polymer processing was used to prepare the ceramic at x = 0.06, showing a recoverable energy density of 6.5 J/cm³ and an energy efficiency of 84 % at 450 kV/cm. Additionally, the ceramic shows remarkable stability within 30–150 °C range, with an efficiency variation of 5.9 %. Furthermore, it performs well in actual discharge energy density (3.22 J/cm³) and power density (131 MW/cm³) at 240 kV/cm.