Enhanced energy storage performance in AgNbO 3 antiferroelectric ceramics via Eu 3+ substitution

Dielectric capacitors are widely concerned because of high-power density. It is essential to develop lead-free materials with high recoverable energy density ( W rec ). Herein, the Ag 1–3 x Eu x NbO 3 (AEN x ) ceramics with x = 0, 0.01, 0.02, and 0.04 were synthesized via a traditional solid-state reaction method. The effects of Eu 3+ additions on the phase, microstructure, and energy-storage performance of AgNbO 3 (AN) antiferroelectric ceramics were systematically studied. The results show that a few Eu doping do not change the perovskite structure of AN, but reduce the phase-transition temperatures of the monoclinic M1-M2 and M2-M3 phases, as well as the tolerance factor and the grain size. These, in turn, lead to the improved antiferroelectric phase stability and enhanced breakdown strength. Consequently, a large W rec of 3.32 J/cm 3 and an energy storage efficiency ( η ) of 40% were obtained in Ag 0.97 Eu 0.01 NbO 3 ceramic at an applied electric field of 220 kV/cm, which exhibited satisfactory thermal stability at 30–130 °C. Furthermore, the Eu 3+ doped ceramics exhibit an excellent practical charging/discharging efficiency (< 60 ns). This work shows that the energy storage performance of AN-based ceramics was significantly optimized by Eu doping, making them competitive candidate materials for pulsed power systems.