Abstract: There has been a growing effort to convert solar energy into electricity in recent years. In order to get a stable solar cell system and acquire a high incident photon-to-current conversion efficiency(IPCE), two novel rhenium(Ⅰ) bipyridyl and ruthenium(Ⅱ) tris-bipyridyl photosensitive dyes were synthesized, the ethoxycarbonyl group in the dyes could be employed for covalently linking to the surface of the nanostructured TiO₂. Their structures, photophysical and electrochemical properties were studied. The UV-Vis absorption maxima were 382 and 476 nm; emission maxima were 622 and 672 nm, respectively. The Re(Ⅰ/Ⅱ) oxidation potential is significantly positive than that of Ru(Ⅱ/Ⅲ) which provides a larger driving force for electron transfer. The results show that they both have proper redox potentials, enough stability and are suitable for being used as photosensitizers of solar cells.

Key words: Photosensitive dyes, Solar cells, Fluorescence spectrun, Redox potentials