铁电材料中的大电卡效应

Large Electrocaloric Effect in Ferroelectric Materials

电卡效应在实现高效率和小尺寸的固态制冷器件方面具有巨大的潜力。本文介绍了获得大电卡效应的热力学原理,评述了近年来电卡效应的实验表征工作,发展了一种直接测量电卡效应熵变或温度变化的方法。结果表明:驰豫型铁电体聚合物和一级相变聚合物材料表现出较大的电卡效应。综合最近在BaTiO3单晶和多层陶瓷电容器的工作,以及铁电制冷器件的尝试,电卡效应表现出诱人的应用前景。

The electrocaloric effect （ECE） in polar materials shows great potential in realizing high efficient solid-state cooling devices with a smaller size and high efficiency. The thermodynamic theory was introduced in order to achieve a large ECE in ferroelectrics. The previous experimental researches were reviewed and discussed. A novel method to directly measure the ECE entropy change and temperature change was developed. Results indi- cated that the relaxor ferroelectric polymers and first-order phase transition polymers demonstrated larger ECE. Recently published larger electrocaloric effect in BaTiO3 crystal and multilayer ceramic capacitors, and the proto- type ferroelectric cooling devices reveal attractive application prospects in the near future.