Electrocaloric response near room temperature in Zr- and Sn-doped BaTiO3 systems.

The electrocaloric effect (ECE) in (1-x)BaZr0.18 Ti0.82O3-(x)BaSn0.11Ti0.89O3 (BZT18-BST11, 0.1≤x≤0.5) ceramics is investigated near room temperature using a calorimetry method. The ceramics exhibit relaxor-like ferroelectric characteristics and by merging phases, a large electrocaloric (EC) response is observed in the system. The largest entropy change is 4.8 Jkg(-1) K(-1) (along with a temperature change of 3.5 K), which is induced under an electric field of 10 MV m(-1) for the 0.8 BaZr0.18Ti0.82O3-0.2 BaSn0.11Ti0.89O3 ceramics. This result reveals that the coexistence of multiple phases improves the ECE of the ceramics, which provides an effective route to achieve a large EC response using a small electric field.This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.