Engineering Recycled Polystyrene with SnO2 Nanofiller for Sustainable Optoelectronic Applications

Polymer nanocomposites have emerged as promising materials for next-generation optoelectronic technologies, offering a unique synergy between the tunable properties of polymers and the multifunctionality of inorganic nanoparticles. In this study, we explore the development of sustainable nanocomposite films by incorporating tin dioxide (SnO₂) nanoparticles into recycled polystyrene (rPS), aiming to enhance the optical and electronic properties of the base polymer. Nanocomposite films were fabricated via a solution casting technique with varying SnO₂ loadings (1–7 wt%), followed by comprehensive characterization using X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and UV-visible spectroscopy. The analysis confirmed successful integration and uniform dispersion of SnO₂ nanoparticles at lower concentrations, leading to significant modifications in the optical characteristics of rPS. Notably, the nanocomposites exhibited enhanced light absorption, increased refractive index, and a notable reduction in the optical band gap from 3.397 eV in recycled polystyrene (rPS) to 3.095 eV at 7 wt% SnO₂. Additionally, third-order nonlinear optical susceptibility χ(3) and nonlinear refractive index (n₂) values increased with SnO₂ content, underscoring the material’s potential for photonic applications. The findings suggest that rPS/SnO2 nanocomposites hold promise for developing sustainable materials for optoelectronic devices.