Enhanced electrocaloric effect in relaxor ferroelectric polymers through hot press processing

Electrocaloric relaxor ferroelectric polymers have been considered as dominant polymer materials for refrigeration applications. However, the magnitude of the electrocaloric effect remains relatively small, especially in the low electric field regime. Here, it is reported that using hot pressing at 40 MPa under a holding temperature of 100 °C and a holding time of 10 min as a postprocessing method, an improved electrocaloric temperature change of 4.7 K is achieved under a low electric field of 50 MV m−1, which exceeds pristine polymers by over 50%. The enhanced electrocaloric response is attributed to the stabilization of all-trans conformation caused by hot pressing, which facilitates the ease of electric field-induced disorder-to-order phase transition.