Influence of pyridine ligand nature and the corresponding ruthenium(II) dye molecular structure on the performance of dye-sensitized solar cells.

cis-[Ru(bpy)(2)(L(n))]Cl(2) (n = 1, L(1) = 4-carboxy-2-(2'-pyridyl)quinoline (); n = 2, L(2) = 2,2'-pyridine-4,4'-dicarboxylic acid ()); and cis-[Ru(bpy)(2)(L')(2))]Cl(2) (L' = 4-pyridinecarboxylic acid ()) complexes, with surface anchoring groups, are prepared from the reaction of cis-[Ru(bpy)(2)Cl(2)] () with the appropriate ligand (L(1), L(2), L'). Ion exchange in aqueous solution with NH(4)PF(6) gives the corresponding bis(hexafluorophosphate) derivatives cis-[Ru(bpy)(2)(L(1))](PF(6))(2) (), cis-[Ru(bpy)(2)(L(2))](PF(6))(2) () and cis-[Ru(bpy)(2)(L')(2)](PF(6))(2) (), respectively. The photo-electrochemical properties of the dyes () are investigated and the efficiency of the corresponding dye sensitized solar cells is compared to a N719 sensitized device, under similar fabrication and testing conditions.