Electro-caloric effect in lead-free ferroelectric Ba-1 (-) Ca-x(x)(Zr0.1Ti0.9)(0.925) Sn0.075O3 ceramics

摘要

The influence of the incorporation of Calcium in lead-free ferroelectric Ba(Zr0.1Ti0.9)(0.925)Sn0.075O3 perovskite on its structural phase transition, dielectric properties, ferroelectric behavior, pyroelectric current, and electrocaloric effect was investigated. X-ray diffraction study allowed the identification of a continuous solid solution in the composition range 0 <= x <= 20 mol%. Dielectric and pyroelectric measurements permitted to determine the exits phase transition. The adiabatic temperature change Delta T was calculated by the indirect method from the thermal variation of P-E hysteresis loops using the Maxwell relation. The incorporation of Calcium was found to increase the electrocaloric responsivity within a broad range of temperature with an optimum of Delta T/Delta E=0.27 K nun/kV observed for x=15 mol%. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.