LAUSR

Abstract Herein, natural green and red dyes have been extracted from Malabar spinach (Basella alba) and red spinach (Amaranthus dubius), respectively, and were used as a sensitizer source for TiO2 photoanode based dye sensitized solar cell (DSSC). The cell efficiency of the developed DSSC sensitized with single individual green and red dyes were obtained, 0.466% and 0.531%, respectively. To improve the cell efficiency of natural dye-based DSSC, natural green and red dyes have been combined at 5 different volume ratios, to find the optimum combination of dyes. From the UV–Vis absorption spectrum, the combination of dyes showed cumulative absorption properties of both single individual dyes. DSSC co-sensitized with the optimum combination of dyes (20% green + 80% red) exhibited the best performance of open circuit voltage of 385 mV, short circuit current of 4.273 mA, fill factor of 0.515 and the highest cell efficiency of 0.847% under 100 mW/cm2 illumination at AM 1.5G condition. The optimised cell efficiency was found 0.847% which is almost 1.82 and 1.6 times higher than that of the single individual green and red dye-sensitized DSSC’s cell efficiency.