| 초록 |
TiO₂ electrodes, adsorbed with two natural dyes of gardenia and cochineal, were used as sensitizers to enhance the conversion efficiency of cocktail dye-sensitized solar cells for light harvesting over a wide range of wavelengths. The adsorption and electrochemical properties of the two dyes were evaluated by considering the adsorption kinetics and electrochemical measurements. The data for the adsorption kinetics of the dyes were acquired by using an adsorption chamber, and fitted with a pseudo second-order model. The photovoltaic performance of a photoelectrode, adsorbed with a single dye, a mixture, or successively adsorbed with two dyes, was evaluated from the current-voltage measurements. Two natural dyes were compared based upon the adsorption modes. The energy conversion efficiency of the TiO₂ electrode, with the successive adsorption of cochineal and gardenia dyes, was 0.48%, which was enhanced compared to single dye adsorption. A double layer of the two natural dyes as sensitizers was successfully formulated on the nanoporous TiO₂ surface based on the differences in the adsorption affinities of gardenia and cochineal. |
