Enhancement of Solar Cell Performance with Layered Filler Graphite for Natural Dye Sensitized Solar Cell

Abstract A dye-sensitized solar cell (DSSC) consists of four crucial components: a photoanode, electrolyte, sensitizer, and photocathode. The stability, efficiency, and sustainability of a DSSC rely on these components. In this study, a biopolymer (chitosan) with graphite filler has been utilized as the electrolyte system to address sealing and leakage issues associated with liquid electrolytes. Chitosan, with its β(1–4) linked 2-amino-deoxy-D-glucopyranose units, exhibits a polycationic character that enhances anionic interactions, forming a polyelectrolyte complex. Furthermore, chitosan is biodegradable, eco-friendly, biocompatible, and non-toxic, making it a sustainable choice. The TiO₂ working electrode has been improved with CuO nanopowder to minimize the inherent energy barrier. A cocktail dye, prepared from beetroot and spinach dyes in a 1:1 ratio, is used as the sensitizer, replacing synthetic dyes and enhancing the eco-friendliness of the fabricated DSSC. The reported solar conversion efficiency is approximately 2.3%, with a fill factor of 54%, under an irradiation of 100 mW/cm².