Electrical and magnetic properties of 0–3 Ba(Fe1∕2Nb1∕2)O3/PVDF composites

Abstract

Lead-free Ba(Fe[Formula: see text]Nb[Formula: see text]O3/PVDF 0–3 composites were fabricated using melt-mixing technique. X-ray diffraction, scanning electron microscopy, dielectric, impedance, ac conductivity, magnetic force microscopy (MFM) and vibrating sample magnetometer studies were undertaken to characterize the samples. Average crystallite size of the Ba(Fe[Formula: see text]Nb[Formula: see text]O3 powder, estimated using Williamson–Hall approach, was found to be [Formula: see text][Formula: see text]nm. The filler particles of [Formula: see text][Formula: see text][Formula: see text]m were found to disperse in the polymer matrix of all the composites. Filler concentration-dependent values of real and imaginary parts of complex permittivity showed increasing trend and were seen to follow Bruggeman and Furukawa equations. The data for ac conductivity exhibited negative temperature coefficient of resistance character of the test materials and were found to obey Jonscher’s power law. The correlated barrier hopping model was found to explain satisfactorily the mechanism of charge transport occurring in the system. MFM confirmed the presence of magnetic phases in the composites. Typical magnetization versus applied field curves indicated the possibility of magnetoelectric coupling in the system. Hence, the present composites have shown themselves as potential multi-functional candidate materials for use in high density data storage applications.