Enhancing solar energy harvesting through TiO2-Fe2O3 composite photoanodes sensitized with natural dyes in photovoltaic cells

This study investigated the enhancement of photovoltaic efficiency of dye-sensitized solar cells (DSSCs) through titanium dioxide (TiO2) anodes composite with iron oxide (Fe2O3). TiO2 with Fe2O3 at different weight percentages (0–30 wt%) were employed as photoanodes in DSSCs, prepared via mechanical mixing. Natural dyes extracted from Chrysanthemum
violet and Alstroemeria flower petals were used as sensitizers, with platinum (Pt) cathode being employed to facilitate the photocatalytic process. The electronic excitation and molecule vibration characteristics of the dye molecules were investigated by UV-Vis and FTIR spectroscopy, respectively. For the analysis of the photovoltaic parameters, electrochemical characterizations were performed. The performances of the Chrysanthemum violet dye-sensitized cells with 10%, 20%, and 30% composite were 3.24%, 5.25%, and 4.15%, respectively, compared to 1.35% for the mere TiO2 cells. Similarly, the photovoltaic conversion yields of the Alstroemeria dye sensitized cells were 3.54%, 6.33%, and 5.74%, while the mere TiO2 cells showed 1.74%. In both cases, composite with 20% Fe2O3 resulted in the highest efficiency. The findings indicate that this doping technique substantially improves the performance of DSSCs, reaching up to four times the efficiency compared to the mere TiO2 cells. These results are promising and reinforce the potential of DSSCs in sustainable
electricity production.