Estudio de colorantes naturales en aplicaciones de celdas solares

Due to the high solar radiation, constant over the whole year, solar energy is one of the most promising energy sources of the Caribbean for the next decades. But up to now this potential is not used, mainly due to the high costs of solar cells. Solar energy conversion is mainly dominated by expensive cells based on silicon. A promising alternative is the dye sensitized solar cell (DSSC) based on Titanium dioxide (TiO2), which has generated considerable interest in the last years. Thus, the objective of this study was to analyse and optimize the DSSCs’ performance depending on their preparation and lighting condition. Therefore, five different natural dyes were extracted from local Colombian fruits and vegetables, such as Achiote, Agraz, Corozo, Mora and Remolacha. They were characterized using an UV-Spectrophotometer and used as sensitizers to fabricate the DSSCs. To optimize the DSSCs, different conditions and parameters were changed. It was thereby found that beside the fruit that was used, also the thickness of the TiO2 layer and the preparation procedure of the dye solution have a direct impact on the cell efficiency. The cells fabricated with achiote dye solution were found to have the best efficiency, reaching up to 0,21% under sun and 0,075% under a halogen lamp. The study was executed in the context of internships at the Universidad del Norte in Barranquilla, Colombia, which was enabled by the DAAD through RISE program scholarships.