Effect of Natural Dye Co-Sensitization on the Performance of Dye-Sensitized Solar Cells (DSSCS) Based on Anthocyanin and Betalain Pigments Sensitisation

Abstract

Dye-sensitized solar cells (DSSCs) were prepared using natural pigments containing anthocyanin and betalain extracted from Flame tree and Bougainvillea glabra flowers respectively as sensitizers. The dyes were used as lone sensitizers exploring anthocyanin and betalain separately and as co-sensitizers exploring the combined anthocyanin and betalain (water extract) and combined anthocyanin and betalain (ethanol extract) separately. The effects of the sensitizers on the performance of the DSSCs were investigated, the study reveals that all the cells possess comparable values of V of about 0.55 0.1 V. However, of the two lone sensitisers,oc betalain based device gave a better efficiency of 0.21% while anthocynin based device achieved 0.17 %, this is attributed to their different anchoring functional groups. The, combined anthocyanin and betalain dyes (water extract) had the highest conversion efficiency of 0.26 % suggesting dye synergic absorption effect as a result of co-sensitisation, the lower efficiency of 0.24 %) achieved by combined anthocyanin and betalain (ethanol extract) is attributed to the contributory effect of the extraction solvents