A new ruthenium sensitizer containing dipyridylamine ligand for effective nanocrystalline dye-sensitized solar cells

► Two novel ruthenium bipyridyl sensitizers based on dipyridylamine ligands as ancillary ligand. ► The σ-donating power of the dipyridylamine red-shift the metal-to-ligand charge transfer (MLCT) band. ► The increasing conjugation length of the ancillary ligand influence the cell performance in DSSCs.