Theoretical investigation of the structural, optoelectronic, and the application of waste graphene oxide/polymer nanocomposite as a photosensitizer

Abstract

The negligence of used waste polymers often results in the waste of resources and constitutes serious environmental pollutants. Therefore, it becomes necessary to practically provide a means of converting these waste polymers to useful resources. For this purpose, the potential applicability of some selected waste polymers as the active photosensitizer material in dye-sensitized solar cells were exploited using density functional theory. In this research work, density function theory (DFT) is applied to investigate the interaction of graphene oxide (GO) with monomers of Polypyrrole (PPy), Poly (phenylene vinylene) (PPV), Poly(vinyl alcohol) (PVA), and Polyvinyl Pyrrolidone (PVP) polymers. The geometrical structures of the hybridized nanocomposites GO-PPy, GO-PPV, GO-PVA, and GO-PVP are fully optimized at wB97XD/6-311++G(d,p) computational method. All of the nanocomposites’ optoelectronic properties, the excitation type and the wavelengths, oscillator strengths, as well as the dominant transitions were calculated. Atoms-in-molecules (AIM) and natural bond orbital (NBO) analysis were used to analyze the strength and nature of the composites. The results of the ground state energy gap revealed that the hybridized nanocomposites are semiconducting in nature while the 3.7020 eV energy gap of the GO-PVA makes it the most stable among the various nanocomposites. The thermodynamic calculation of the various nanocomposites shows that the GO-PVA nanocomposite is highly endothermic among the various nanocomposites with free energy value of 353.71kcal mol−1. The results of the density of state (DOS) analysis show that the p-orbitals in all of the different nanocomposites had the highest density contribution to the frontier molecular orbitals, and are also found to dominate the anti-bonding states densities.