Organic and inorganic relaxor ferroelectrics with giant electrocaloric effect

摘要

The electrocaloric effect u0002ECEu0003 in inorganic thin film and organic relaxor ferroelectrics isninvestigated by directly measuring the ECE around room temperature. The results reveal thatngiant ECEs can be obtained in the high energy electron irradiated polyu0002vinylidenenfluoride-trifluoroethyleneu0003 relaxor copolymer and in the La-doped Pbu0002ZrTiu0003O3 relaxor ceramic thinnfilms, which are much larger than that from the normal ferroelectric counterparts. The large ECEnobserved, compared with normal ferroelectrics, is likely caused by the large number of disorderednfluctuating polarization entities in relaxor ferroelectrics which can lead to extra entropyncontributions and larger ECE. © 2010 American Institute of Physics. u0004doi:10.1063/1.3501975