Preparation, characterization, and improvement in the energy storage properties of Bi(Li0.5Ta0.5)O3 modified Na0.5K0.5NbO3 ceramic system

Abstract (1-x)K0.5Na0.5NbO3-xBi (Li0.5Ta0.5)O3 (x = 0, 0.05, 0.10, 0.15, 0.20) ceramics were processed using a solid-state sintering route. All the sintered samples were characterized in terms of phase, microstructure, dielectric, ferroelectric, and energy storage characteristics. A structural variation from orthorhombic to pseudo-cubic was observed with an increase in x from 0 to 0.20. At x ≥ 0.10, in addition to the parent phase, the formation of a secondary phase was also observed. The grain size decreased with an increase in x value to 0.15 and then increased, for example, at x = 0.20. A charged energy density (Ws) of ∼1.99 J/cm3 along with a recoverable energy density (Wrec) of ∼1.10 J/cm3 was obtained for the x = 0.15 composition. Moreover, the composition with x = 0.15 exhibited high stability of dielectric constant at temperatures ranging from 30 to 371 °C.