Energy storage properties and electrocaloric effect of Ba_(0.65)Sr_(0.35)TiO_3 ceramics near room temperature

摘要

AbstractBa0.65Sr0.35TiO3(BST) ceramics were synthesized by sol–gel route. The diffusion phase transition (DPT) characteristic was found in the temperature range from 150 to − 35 °C. The value of the DPT parameterγvalues are 1.53 and 1.75, respectively at applied dc field of 0 and 16.7 kV/cm. It is implied that the phase transition of BST ceramics become more diffuse under the applied electric field. Temperature dependent polarization–electric field hysteresis loops were studied. It was found that the energy storage properties and electrocaloric effect near room temperature were the function of electric fields. The maximum value of recoverable energy density was 0.2812 J/cm3with energy storage efficiency (η) of 78.67% obtained at room temperature under an electric field of 75 kV/cm. The largestηcan achieve 98% under low electric field of 50 kV/cm. A large electrocaloric temperature change (ΔTmax = 0.49 K) near room temperature was obtained by indirect method. Taken together, the ceramics have a promising candidate for energy-storage applications and cooling systems in the room temperature.