Dielectric and energy storage density studies in electrospun fiber mats of polyvinylidene fluoride (PVDF)/zinc ferrite (ZnFe2O4) multiferroic composite

摘要

Flexible free standing electrospun poly (vinylidene fluoride)/ZnFe2O4 composite fiber mats were synthesized through electrospinning technique. Structural and morphological studies of PVDF/ZnFe2O4 composite fibers were examined by X-ray diffraction and scanning electron microscopy. The functional groups and the percentage of beta phase were analysed using FTIR studies. 92% beta phase was achieved with the incorporation of ZnFe2O4 filler. The enhancement in dielectric and ferroelectric properties of the composite fiber mats were observed with a maximum dielectric constant and polarization values of 15 and 0.72 mu C/cm(2) respectively for 20 wt% filler loading. The domain switching behaviour of the mats were analysed using DC-EFM. Vibration sample magnetometry results revealed the antiferromagnetic nature of the composite fiber mats with a maximum magnetization of 0.18 emu/cm(3). Further, the energy storage density of the mats was studied and a maximum energy storage density of 239 mJ/cm(3) was obtained which was 1.4 times than that of pure PVDF mat.