Study of electrical transport, dielectric and magnetic properties of NiFe2O4-PVDF nanocomposite film

Abstract

In this study, Nickel ferrite (NiFe 2 O 4 ) nanoparticle (NFO) and Nickel ferrite - Polyvinylidene fluoride (NFO-PVDF) nanocomposite films have been synthesized by chemical route method. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirm the formation of pure phase NFO nanoparticles. The electrical transport and dielectric properties of nanocomposite film have been reported in the frequency range 200 Hz ≤ f ≤ 2 MHz and temperature range 303 ≤ T ≤ 410 K. The activation energy (E a ) and barrier height ( φ b ) are enhanced for NFO-PVDF composite film compare to pure PVDF film. The high value of ideality factor implies that the hopping charge transport mechanism is dominated in the composite film. The AC conductivity also follows correlated barrier hopping (CBH) mechanism. The dielectric permittivity increases with filler (NFO) concentration and temperature. Dielectric permittivity and electric modulus are well fitted with the modified Cole-Cole and KWW function. Non-Debye type of relaxation phenomenon is observed in higher temperature and higher filler concentration. The magnetic measurement of the NFO-PVDF composite depicts the soft ferromagnetic behaviour of the materials. The saturation magnetization and hysteresis loop area are increased in higher filler (NFO) concentration. Magnetic hysteresis study of 4% NFO-PVDF may show the ferrimagnetism with supressed saturation magnetization than pure NFO. However, the saturation magnetization and hysteresis loop area are increased in 8% filler (NFO) concentration. • Two distinct activations have been observed in the samples. • A hump is observed in temperature vs dielectric constant study. • Dielectric permittivity enhances in composites over polymer. • Hysteresis loop has been observed in NFO-PVDF composites. • Both magnetic and dielectric properties have been observed in composites.