Micro-structure and optical spectroscopy of PVA/iron oxide polymer nanocomposites

The current research aims to synthesize and investigate the optical spectroscopy of PVA/iron polymer nanocomposites. The polymer films prepared via dissolving powders and charac-terized by XRD, SEM and optical spectroscopy measurements. The analysis of XRD depicted the cubic crystal structure of gamma-Fe2O3 nanoparticles with average crystallite size 42.40 nm. SEM monographs provided the complete interaction between gamma-Fe2O3 and PVA polymer matrix. Optical absorption measurements of the PVA/iron oxide polymer nanocomposites displayed a red shift of the absorption edge with the iron oxide content. The optical indirect energy gaps estimated from optical absorption data decreased from 5.0 to 2.4 eV with the iron oxide content. In addition, the refractive index values enhanced with the concentration of iron oxide. Comparing the energy gap values estimated from Tauc's formula and optical dielectric loss function confirmed the major electronic transitions as direct allowed. The fluorescence spectra of the PVA/iron polymer nanocomposites displayed emission peaks centered at 421, 451 and 469 nm and the intensity reduced with the ratio of iron oxide. (C) 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).