Electrocaloric effect in lead-free 0.5Ba(Zr0.2Ti0.8) O-3-0.5(Ba0.7Ca0.3) TiO3 ceramic measured by direct and indirect methods

摘要

Lead-free 0.5BZT-0.5BCT ferroelectric ceramic was fabricated through the conventional solid-state reaction method. The electrocaloric effect (ECE) of 0.5BZT-0.5BCT was systematically investigated by both direct and indirect methods over a wide temperature range and electric field range. The maximum direct ECE Delta T-EC = 0.464 K occurs at 100 degrees C under the electric field of 6 kV/mm, while the obtained maximum indirect ECE Delta T-EC is 0.26 K when the electric filed is 2 kV/mm at 70 degrees C. ECE of 0.5BZT-0.5BCT ceramic exhibits a fast response speed (2-3 s), good cycle stability, and a wide working temperature range (80-140 degrees C) with Delta T-EC = 0.2 K, which indicates the promising candidate for applications in cooling technologies.