Effect of Cobalt Chloride on the Optical Properties of PVA/PEG Blend

Document Type : Original Article

Authors

Physics Department, Faculty of Science, Zagazig University 44519, Zagazig, Egypt

Abstract

Herein, solution casting technique has been used to prepare films of different composites of cobalt chloride (CoCl2) embedded in a blend of (poly vinyl alcohol (PVA) /poly ethylene glycol (PEG) 72/28 wt.%). Fourier Transform Infra Red (FT-IR) has been used to determine the effect of CoCl2 on the characteristic functional groups of both PVA and PEG. A shift in the absorption edge of the pure blend has been obtained by adding CoCl2 which indicates a decrease in the energy gap (Eg) values based on the CoCl2 content. By increasing the content of CoCl2, the refractive index, the Urbach energy, the dispersion parameters, the moments of the optical spectrum and the static dielectric constants show a reduction in their values compared to these of the pure blend. The oscillator energy gap Eo equals about 2.23 Eg, for the different composites. The calculated values of the penetration depth, for all the composites, exhibit an increase by increasing the wavelength whereas they decrease in the region of the absorption band of the CoCl2 from 420 nm to 750 nm depending on the CoCl2. The optical conductivity of the composites has been increased in the region of the absorption band of the CoCl2.

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