The increasing demand for renewable energy sources has accelerated advancements in organic photovoltaics (OPVs), which have the potential to provide a low-cost, flexible, and environmentally sustainable alternative to traditional silicon solar cells. However, OPVs currently exhibit a lower power conversion efficiency (PCE) of 19%, compared to the 26% efficiency of silicon cells. This inefficiency limits their broader adoption in the solar energy market. The morphology of the conjugated polymer films within OPVs  largely determines the PCE, as it directly influences both light absorption and charge transport. One key factor in shaping this morphology is the aggregation of polymer chains during fabrication. The choice of solvent used in the deposition process plays a crucial role in controlling polymer aggregation, as well as the crystallinity and overall film structure. These solvent-driven changes in morphology ultimately impact the PCE of the OPVs. 
The objective of this research is to explore how different solvents affect the morphology of PM6-based OPVs. To achieve this, PM6 solutions were prepared with varying solvents at different concentrations, followed by spin-coating onto glass substrates to form thin films. Ultraviolet-visible (UV-Vis) spectroscopy was used to measure the absorption spectra of both the solutions and the films, revealing information on polymer aggregation, crystallinity, and the degree of order within the films. Changes in the absorption peak position, width, and intensity are analyzed to reveal the impact of solvent choice on the polymer structure. Data from these measurements help correlate solvent-induced changes in polymer aggregation with improvements in OPV performance. By investigating the relationship between solvent selection and OPV morphology, this research provides valuable insights that contribute to the development of more efficient and cost-effective OPVs.