Large electrocaloric effect of BCTZ/P(VDF-TrFE) 0-3 composites

0-3 type composites of lead-free 0.3(Ba0.7Ca0.3)TiO3-0.7Ba(Zr0.2Ti0.8)O-3 (BCTZ) ceramic filler and poly-vinylidene difluoride trifluomethylene [P(VDF-TrFE) (55/45)] polymer matrix were fabricated. With a fixed BCTZ filler volume fraction at 30 vol%, the ceramic/polymer composites exhibited the largest temperature change (Delta T = 9.1 K) and electrocaloric strength (Delta T/Delta E = 0.18 mu Km/V) under a low electric field of 500 kV/cm. Microstructure and dielectric/ferroelectric characterizations attributed the main reason to a well dispersion of ceramic filler together with few pores, where sufficient and appropriate electric fields were applied not to pores but mainly to higher dielectric BCTZ fillers inside the matrix polymer.

Automated summary

Proper dispersion of ceramic fillers with few pores, along with appropriate electric field application, can enhance the temperature change and electrocaloric strength of ceramic/polymer composites.