Dye-Sensitized Solar Cells Based on a Natural Low Cost Halochromic Sensitizer

Abstract

ABSTRACTSince their re-introduction as new generation solar cells in 1991, dye-sensitized solar cells (DSSCs) have been studied extensively to improve their efficiency and their stability. Few papers have reported the usage of natural dyes in the fabrication of DSSCs. We are most interested in these dyes being easy to extract, low cost and with tunable absorption. For example, Anthocyanin is extracted from red cabbage and is present in a multitude of colors ranging from red to yellow to violet according to the pH. In this study, two industrial types of titanium dioxide powders, the Degussa P 25 and the Crystal 128 with different particle sizes 21 and 200 nm respectively, were used to prepare DSSCs. The dye used is anthocyanin and its color is varied by varying the pH of the medium. The pH effect on the light absorption of anthocyanin in the visible range and the optical properties of titanium dioxide dyed with anthocyanin and coumarin 102 are investigated using UV-Vis spectroscopy. The open-circuit voltage of all the samples is tested and it if found out that it is dependant on the dye color.