Significantly enhanced energy storage properties of Nd³⁺ doped AgNbO₃ lead-free antiferroelectric ceramics

Lead-free dielectric capacitors for energy storage device have attracted increasing attention recently because of their high-power density and superior temperature stability. In this work, Nd-doped silver niobate (AgNbO₃, abbreviated as AN) lead-free antiferroelectric ceramics were prepared by utilizing traditional solid state reaction method. A large energy storage density of 4.6 J/cm³ and an efficiency of 62.5% were simultaneously obtained in the 1% Nd-doped AN sample with an outstanding power density of 54.0 MW/cm³ and an ultrafast discharge speed (t_0.9) of 59.2 ns. Additionally, the 1% Nd-doped AN ceramic demonstrates a good temperature stability from 25 ℃ to 130 ℃. The excellent energy storage properties of the 1% Nd-doped ceramic is ascribed to the enhanced breakdown electric field induced by grain size engineering and the construction of phase structure via heterovalent substitution at the A-site of the lattice structure at room temperature. Our present work suggests that the 1% Nd-doped AN ceramic show promise for energy storage application in miniaturized mobile electronic devices and high-power equipment.