Structural, Optical, Electrochemical Properties and Performance of PEO/PMMA/Al ₂ O ₃ Polymer Nanocomposites in Dye-Sensitized Solar Cells

This work presents the development of polymer nanocomposite electrolytes tailored for dye-sensitized solar cells (DSSCs). Thin films were fabricated by incorporating aluminum oxide (Al2O3) nanoparticles (2 and 4 wt.%) into a poly(ethylene oxide)–poly(methyl methacrylate) (PEO–PMMA) matrix via solution casting. Structural and spectroscopic analyses (XRD, FTIR) confirmed enhanced amorphization and robust polymer-nanofiller interactions, leading to improved ionic conductivity. UV–Vis spectroscopy revealed bandgap modifications, reflecting nanoparticle-induced change in the electronic structure. Cyclic voltammetry of the 4 wt.% Al2O3 film (PEPM824) demonstrated stable redox behavior and efficient ion transport. When integrated into DSSCs, PEPM824 achieved a power conversion efficiency of 1.89%, outperforming the pristine system. These results highlight the potential of PEO–PMMA/Al2O3 nanocomposites as promising, flexible, and high-performance electrolytes for next-generation energy conversion devices.