Short review: Natural pigments photosensitizer for dye-sensitized solar cell (DSSC)

Dye sensitized solar cell (DSSC) is the third generation solar cell that consists of semiconductor electrode, dye, electrolyte and counter electrode. Among all of the components, dyes perform a primary role in absorbing solar energy and converting it to electrical energy. Therefore, the DSSC performance is absolutely depends on the type of dye sensitizer used. The traditional DSSC used Ruthenium (Ru) complexes as the sensitizer. However, Ru has several limitations due to high cost, rarity and complexity to be synthesized. Thus, in exchange to metal complex Ru dyes, current researches are focusing on natural dyes that are extracted from plants. This paper emphasizes on various researches which involved natural dye pigments; anthocyanin, chlorophyll and betalain. Based on the data comparisons, betalain pigments extracted from purple wild sicilian prickly pear dye has recorded the highest energy conversion efficiency of 2.06%. This has made the betalain pigments as a promising candidate for the best natural dye sensitizer, followed by anthocyanin and chlorophyll.