Synthesis, characterization, and electrical properties of Nd3+‐doped (Bi0.4Na0.2K0.2Ba0.2)TiO3 high‐entropy ceramics

Abstract

AbstractRecently, high‐entropy perovskites have attracted considerable attention due to their diverse chemical composition and multifunctionality. In this study, the high‐entropy approach was employed in a (Bi0.4Na0.2K0.2Ba0.2)TiO3 matrix, and Nd3+ was introduced to enhance the configurational entropy and modify its dielectric and ferroelectric properties. Notably, despite Nd3+ doping, all samples maintained a tetragonal perovskite structure at room temperature. The configurational entropy increased with the Nd3+ concentration, consequently leading to a gradual decline in the ferroelectric properties along with the associated temperature (Tm) and maximum dielectric constant (εm). The P–E loops of the ceramics also became thinner as Pm and Pr decreased, resulting in a slow decrease in the recoverable energy density (Wrec) and a simultaneous increase in the energy storage efficiency (η). Especially, the energy storage performance reached its peak at an Nd3+ concentration of 12 mol%, exhibiting an energy storage efficiency of 85.8% and a recoverable energy storage density of 0.74 J/cm3 at a low electric field of 100 kV/cm. These results highlight the potential of this material for dielectric applications in low electric fields and contribute to the advancement of alternative high‐entropy energy storage perovskite ceramics.