Enhanced low‐field energy storage performance in Nd3+‐doped (Bi0.40K0.2Na0.2Sr0.2)TiO3 high‐entropy ceramics

Abstract The burgeoning requirement for compact electronic devices has intensified research into lead‐free dielectric ceramics that offer superior recoverable energy storage density and efficiency at low electric fields. In this study, we report the synthesis of Nd 3+ ‐doped (Bi 0.4 K 0.2 Na 0.2 Sr 0.2 )TiO 3 perovskite ceramics via the solid‐state reaction technique. The synthesized ceramics adopted a tetragonal crystal structure. As the concentration of Nd 3+ ions increased, both the maximum dielectric constant ( ε m ) and its corresponding temperature ( T m ) decrease. The incorporation of Nd 3+ ions perturbed the long‐range ferroelectric order, leading to diminished maximum polarization ( P m ) and remanent polarization ( P r ). The ceramics achieved optimal properties with 12 mol% Nd 3+ doping, showcasing a significant recoverable energy storage density of 1.50 J/cm 3 at a low electric field of 140 kV/cm, along with an exceptional storage efficiency of 94.6%. This research not only highlights a promising candidate for dielectric materials in low electric field applications but also introduces an innovative approach to enhance energy storage performance.