Utilization of natural carotenoids as photosensitizers for dye-sensitized solar cells

摘要

The dye-sensitized solar cells (DSCs) were assembled by using natural carotenoids, crocetin (8,8'-diapocarotenedioic acid) and crocin (crocetin-di-gentiobioside), as sensitizers and their photoelectrochemical properties were investigated taking a presence or absence of car-boxylic group in the dye molecule into consideration. In these carotenoids, crocetin that has carboxylic groups in the molecule can attach effectively to the surface of TiO_2 film so that it performed the best photosensitized effect resulting in the short-circuit photocurrent with 2.84 mA under irradiation of 1.0 cm~2. On the other hand, crocin that has no carboxylic group in the molecule showed lower photoelectrochemical performance because of its lower affinity to the surface of TiO_2 film. These results indicate that it is possible to apply carot-enoid as sensitizers for DSCs at the presence of effective function groups.