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

摘要

Pure poly (ethylene oxide) (PEO) films and PEO-FeCl_3 filmsof various concentration were prepared and studied for thermal andoptical properties. Various analytical techniques like XRD, EDX, SEM,TGA, and UV were used to examine the structural properties of PEO andPEO-FeCl_3 systems. X-ray scans (XRD) revealed the existence of somecrystalline part in the PEO matrix. The concentration of FeCl_3 has agreat effect on the crystallinity of PEO. Thermogravimetric analysis(TGA) data established that accumulation of FeCl_3 to PEO filmsenhanced the thermal stability of PEO. The optical properties of thesesystems were also studied in the UV-Visible region as a function ofFeCl_3 concentration at room temperature. The obtained data wereanalyzed in terms of absorption formula for non-crystalline materials.From the measured absorption data optical energy gaps (E_{opt}) weredetermined. The optical energy gap was found to decrease with theincrease in FeCl_3 concentration, which indicates that FeCl_3concentration had a significant influence on optical energy band gap.The absorption coefficient increased sharply at concentration ofFeCl_3 (5%) wt as compared with the pure PEO.