Structural and Optical Characteristics of PVA Films Doped with MgO Nanocrystalline
Aiyeshah Alhodaib *
Department of Physics, College of Science, Qassim University, Buraydah 51452, Saudi Arabia.
Lama Al-Huwaymili
Department of Physics, College of Science, Qassim University, Buraydah 51452, Saudi Arabia.
*Author to whom correspondence should be addressed.
Abstract
The integration of Magnesium oxide nanoparticles (MgO NPs) into polyvinyl alcohol (PVA) matrix creates nanocomposite films that are considered one of the most capable materials for cost-effective, reliable, and solar-saving energy in daily desired applications. The structural and optical properties of MgO NPs were studied using X-ray diffraction (XRD), and Ultraviolet–visible spectroscopy (UV–vis) at different weight percentages (2, 4, 6, and 8 wt%) of MgO NPs that were incorporated into PVA by the solution casting method. The results showed that all samples have a cubic crystal structure with an observed increase in crystal size as the MgO concentration increases. FTIR analysis indicated that there is an interaction between MgO and the PVA through hydrogen bonding. The energy band gap and tail of localized state of PVA/MgO nanocomposites have been calculated by using Tauc and Urbach relations, respectively. The band gap of the nanocomposite samples decreases as MgO wt% increases. The loading of 2 to 8 wt% of MgO NPs in the PVA matrix caused a significant reduction in direct bandgap, indirect bandgap, and Urbach energy. These results showed that the spectroscopic properties of PVA-MgO NP films were modified considerably with small loadings of MgO NPs in the PVA matrix due to cross-linking formation between the nanoparticles and the polymer. In addition, this increase in percentages has affected the optical parameters by enhancing the optical proficiency for the prepared samples with a noticeable slight shift to the visible region to improve their efficiency to be used as photocatalytic and energy-saving applications in more reliable and effective methods. This study has yielded significant insights that may aid in the advancement of optoelectronic applications in industries by reducing costs. These results could be instrumental in enhancing production processes and making the use of more viable and cost-effective options for industrial operations.
Keywords: Sol–gel, MgO nanoparticles, optical band gap, urbach energy, dispersion energy