Sustainable Solar Energy Harvesting by <i>Neolamarckia cadamba</i> Leaf Extract and Comparative Study of Solvent Effect on Cell Performance

ABSTRACT Natural dye‐based dye‐sensitized solar cells (NDSSCs) are an emerging type of solar cell. Natural photosensitizers are eco‐friendly and cost‐effective, and serve as a better alternative to synthetic and organic dyes used in DSSCs. The nature of the solvent and the dye substrate used in dye extraction play a crucial role, affecting dye properties and, consequently, the performance of NDSSCs. This paper focuses on dye extraction from fresh and dried leaves of Neolamarckia cadamba (NC) using different solvents (acetone, ethanol, and methanol) and compares the overall efficiency of the fabricated NDSSCs. The study found that acetone is the best solvent among the three solvents. Acetone‐based NDSSC (FTO/TTIP/TiO 2 /ANC/electrolyte/Pt) displayed a V oc of 0.77 V, fill factor (FF) of 0.33, J sc of 9.42 mA/cm 2 , and an efficiency of 2.41%. This performance is quite comparable to the standard N719 dye‐based cell (FTO/TTIP/TiO 2 /N719/electrolyte/Pt) fabricated under identical lab conditions, which exhibits a V oc of 0.53 V, FF 0.35, J SC of 25 mA/cm 2 , and an efficiency is 4.7%. Overall, NC has the potential to become an alternative to chemical and hazardous dyes, and further exploration and investigation may improve its performance in sustainable way.