Performance of the dye‐sensitized solar cells fabricated using natural dyes from Ixora coccinea flowers and Cymbopogon schoenanthus leaves as sensitizers

Summary In this study, the chlorophyll and anthocyanin natural dyes were extracted from Cymbopogon schoenanthus leaves and Ixora coccinea flowers, respectively. Thereafter, these dyes were used as sensitizers in the TiO2‐based dye‐sensitized solar cells (DSSCs). Ten solvents were used for solubilizing the dyes. Amongst the 10 solvents, the ethanol showed the highest absorption spectra for the anthocyanin and chlorophyll molecules. Temperature significantly affected the yield of the natural dyes. It was seen that an optimal extraction temperature of 70°C and 80°C results to higher anthocyanin and chlorophyll yields, respectively. However, an extraction temperature above 70°C and 80°C has shown a sharply decrease in the anthocyanin and chlorophyll concentrations, respectively. Also, the solution of acidic extraction, especially with a pH value of 4, increased the dyes concentrations. As seen in the results, the chlorophyll‐sensitized DSSCs had 0.23% conversion efficiency (ƞ), short‐circuit current (Isc) of 0.9 mA/cm–2, open‐circuit voltage (Voc) of 0.51 V, and 49.13% fill factor (FF). Meanwhile, the anthocyanin‐sensitized DSSCs showed 0.16% ƞ, 0.4 mA/cm–2 Isc, 0.53 V Voc, and 75.93% FF.