Photochemical properties of dye-sensitized solar cell using mixed natural dyes extracted from Gardenia Jasminoide Ellis

Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Gardenia Jasminoide Ellis as sensitizers. Different mixtures of natural dyes (i.e., gardenia yellow (GY) and gardenia blue (GB)) extracted from the natural flower of Gardenia Jasminoide Ellis were used to produce photosensitivity by interaction between the chemisorption and physisorption of the dyes and the surface of porous TiO2 film. In this paper, the adsorption characteristics for harvesting sunlight and the electrochemical behavior of electron transfer using GY and GB, and also a mixture of both dyes were investigated. The light absorption spectrum of the mixed extract contained peaks corresponding to the contributions from both gardenia yellow and gardenia blue extracts. The energy conversion efficiency of the TiO2 electrode with successive adsorptions of GY and GB dye (S-GYB) was 0.59%, which is enhanced compared to the cases of single-dye adsorption.