This study investigates the eff ect of two diff erent combination methods of natural pigments including anthocyanin from saffron petals and chlorophyll from walnut shell, as sensitizers on the photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs). The photovoltaic properties of chlorophyll and anthocyanin were separately studied and then were blended in a cocktail in equal proportions, by two different combination recipes, to study the photovoltaic properties of the mixed dyes. The first method is the common used method, and in the second one which is proposed in this study, the pigments are layered on top of each other according to their molecular structures. The experimental results showed that the DSSC sensitized with solely anthocyanin exhibited an open-circuit voltage (Voc) of 0.397 V, short circuit current density (Jsc) of 2.32 mA/cm2, fill factor (FF) of 0.71 and conversion efficiency of 0.66%. In the cell sensitized with chlorophyll these parameters were 0.79 V, 0.939 mA/cm2, 0.71 and 0.528%, respectively. The DSSC sensitized with the common combination method of chlorophyll and anthocyanin exhibited Voc of 0.72 V, Jsc of 1.61 mA/cm2, FF of 0.73 and conversion efficiency of 0.85%. While in the cell sensitized with the layered combination of chlorophyll and anthocyanin these parameters were 0.71 V, 1.38 mA/cm2, 0.74 and 0.74%, respectively. The results imply that the combination of pigments can meaningfully improve the cell performance, However the way of pigments combination affects this improvement.

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