Preparation, morphology, and thermal and optical properties of thin films of ferric chloride/polyethylene oxide composites


Abstract: Pure poly (ethylene oxide) (PEO) films and PEO-FeCl_3 films of various concentration were prepared and studied for thermal and optical properties. Various analytical techniques like XRD, EDX, SEM, TGA, and UV were used to examine the structural properties of PEO and PEO-FeCl_3 systems. X-ray scans (XRD) revealed the existence of some crystalline part in the PEO matrix. The concentration of FeCl_3 has a great effect on the crystallinity of PEO. Thermogravimetric analysis (TGA) data established that accumulation of FeCl_3 to PEO films enhanced the thermal stability of PEO. The optical properties of these systems were also studied in the UV-Visible region as a function of FeCl_3 concentration at room temperature. The obtained data were analyzed in terms of absorption formula for non-crystalline materials. From the measured absorption data optical energy gaps (E_{opt}) were determined. The optical energy gap was found to decrease with the increase in FeCl_3 concentration, which indicates that FeCl_3 concentration had a significant influence on optical energy band gap. The absorption coefficient increased sharply at concentration of FeCl_3 (5%) wt as compared with the pure PEO.

Keywords: Poly (ethylene oxide), FeCl_3, XRD, optical properties, TGA, SEM, EDX

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