Electrocaloric behavior and temperature dependent scaling of dynamic hysteresis of BaxSr1-xTiO3 (x = 0.7, 0.8 and 0.9) bulk ceramics

This article presents electrocaloric effect in BaxSr1-xTiO3 ferroelectric ceramics using an indirect approach based on Maxwell’s relations. The peak electrocaloric performance is found to be an adiabatic temperature change of 0.67, 0.83, and 0.61 K and isothermal entropy change of 0.9, 1, and 0.7 J/kg.K for x = 0.7, 0.8, and 0.9, respectively, under an electric field of 33 kV/cm. The electrocaloric coefficient of performance (COP) of materials were also estimated as 17, 5.47, and 5.68 when x = 0.7, 0.8, and 0.9, respectively, in BaxSr1-xTiO3 at 33 kV/cm (303 K). Further, the ferroelectric hysteresis parameters scaling relations of coercive field (E c) and remnant polarization (P r) as a function of temperature have been estimated. The back switching polarization (P bc) as a function of temperature (T) was estimated by the Arrhenius law in order to understand the domain dynamics, and the average activation energy was evaluated.