Photosensitization of nanoporous TiO2 films with natural dye

Dye-sensitized solar cells were assembled by using natural dyes extracted from wormwood, bamboo leaves and red maple leaves as photosensitizers. The Voc values of natural dyes from wormwood, bamboo leaves and maple leaves were 0.67, 0.66 and 0.59, respectively. The ISC values were varied from 2.56 to 5.95 mA cm-2 and the fill factors from 56 to 66%. Based on investigations into the structure and properties of dye molecules, wormwood revealed the best photosensitized effects among several kinds of natural dyes, which is due to the interaction between the carbonyl and hydroxyl groups of anthocyanin and the surface of TiO2; these wormwood extracts act as efficient sensitizers.