UV treatment effect on TiO2 electrodes in dye-sensitized solar cells with N719 sensitizer investigated by infrared absorption spectroscopy

cis-di(thiocyanato)bis(2,2(')-bipyridyl-4,4(')-dicarboxylate)rutheniumu(II) (N719) adsorption on anatase TiO2 electrodes in dye-sensitized solar cells has been investigated using infrared absorption spectroscopy with a multiple internal reflection technique. We have found that the N719 dye dissociatively adsorbs on OH sites to the TiO2 surfaces with its carboxy group. The intentional generation of the OH sites on the TiO2 electrodes with a photocatalytic reaction by UV irradiation in air prior to the N719 dye adsorption is effective in increasing the short-circuit current of the dye-sensitized solar cells. (C) 2008 The Electrochemical Society.