Functionalized phenyl bipyridine ancillary ligand as double recombination inhibitor in ruthenium complex for dye solar cells

Abstract A simple ruthenium(II) polypyridyl complex Ru(II)(dcbp)(L)(NCS) 2 coded as MC 219, where dcbp = 4,4′-dicarboxylic acid-2,2′-bipyridine, L = 4,4′-bis(3,5-di- tert -butyl-4-(hexyloxy)phenyl)-2,2′-bipyridine has been synthesized and fully characterized with IR, NMR, MS, UV–Vis and electrochemical measurements. The incident photon to current conversion efficiency of MC 219 reached its highest 56% at 550 nm. Under standard Air Mass (AM) 1.5 sunlight, the sensitizer MC 219 yielded a short-circuit photocurrent density ( J SC ) of 9.58 mA cm −2 , an open-circuit voltage ( V OC ) of 0.655 V, and a fill factor ( ff ) of 0.733, corresponding to an overall conversion efficiency of 4.6% compared to that of standard N 719 at 7.2% ( J SC of 18.43 mA cm −2 , V OC of 0.582 V, ff of 0.671).