Synthesis and characterization of P(VDF-TrFE)/Cobalt ferrite composite films

Abstract

In this work, PVDF-TrFE/CoFe2O4 nanocomposite free standing films are prepared, and their multiferroic properties are studied. These properties include structural, optical, magnetic, and ferroelectric properties. CoFe2O4 nanoparticles synthesized by the cost effective sol gel method. Free standing PVDF-TrFE/CoFe2O4 nanocomposite films with varying CoFe2O4 content have been prepared using solvent casting (or drying casting method). Structural analysis of all prepared films is done by PANalytical X-Ray Diffractometer. Effect of adding cobalt ferrite (CFO) nanoparticles in PVDF-TrFE matrix is delicately observed and analyzed in detail. The crystallinity of the films is affected by the incorporation of cobalt ferrite nanoparticles into Poly Vinylidene trifluoride P(VDF TrFE). Ferroelectric response at room temperature is studied by measuring polarization versus electric field loops at low frequency 10 Hz and high frequency 400 Hz. Some PVDF TrFE films exhibited saturated ferroelectric hysteresis loops, which show that the addition of TrFE monomers induced a high content β-phase. For low CFO concentration, good ferroelectric response has been achieved. While for higher concentrations, non-saturated ferroelectric hysteresis loops are observed in PVDF-TrFE/CFO films, which confirm lossy capacitive behavior. The effect of CoFe2O4 nanoparticles on the polarization has also been analyzed in detail. An increase in saturation polarization is observed with the addition of CoFe2O4 nanoparticles, attributed to the interfacial effects and interactions between nanoparticles. Fourier transform infrared spectroscopy reveals presence of the beta-phase in all composite films. Reflectance is measured against energy reveals presence of d-d transition associated with the CFO particles. Temperature dependent magnetic response is also observed which show ferromagnetic behavior. Both temperature dependent magnetization and hysteresis behavior have been presented. Data has been analyzed on the bases of Bloch’s law.