Structural, electrical and magnetic properties of polystyrene films filled with AgNO3–FeCl3 mixed fillers

Abstract

The effect of various filling levels (FLs) of mixtures of two transition compounds (X)AgNO3 (10−X) FeCl3, on structural, electrical and magnetic properties of polystyrene (PS) films was investigated. The X-ray diffraction (XRD) displayed an unexpected appearance of a number of crystalline peaks beside the two main peaks characterizing the virgin film. The crystalline peaks were attributed to the cluster formation. The infrared (IR) analysis was used to detect the most notably PS peaks and to clarify the structural variations due to the filling. Certain IR peaks were taken as an evidence for the formation of polaron and/or bipolaron bound states in the polymeric matrix. The direct current (DC) electrical conduction studies revealed a linear temperature dependence of the hopping distance R0 for various FLs. This is an indication that the conduction mechanism can be attributed to one-dimensional intrachain type based on the phonon-assisted charge carrier interpolaron hopping model. The DC magnetic susceptibility results, in the temperature range 90–235K, followed the Curie–Weiss behavior. The positive and negative values of the paramagnetic Curie temperature (θp) indicate the possibility of ferromagnetic and antiferromagnetic exchange interactions between the magnetic centers at low temperatures, respectively. The electron spin resonance (ESR) spectra at the lower values of X depicted a broad signal superimposed on it a narrow one as well as a deformed signal. The ESR investigations at the lower values of X indicated the presence of aggregated Fe+3 confirming the XRD implications about the cluster formation. On the other hand and at higher values of X, an appearance of unresolved five lines of fine structure character was noticed.