Synthesis and Photo Electrochemical Characterization of an Extended π-Conjugated Heteroleptic Ruthenium (II) Complex

Abstract

A new extended π-conjugate heteroleptic ruthenium(II) complex (m-HRD-1) that contains a 4,4’-bis-2-(5(3,5-di-tert-butylphenyl)thiophene-2-yl)vinyl)2,2’-bipyridine as ancillary ligand, 4,4’-dicaboxy-2,2’-bipyridine as anchoring group, and two thiocyanate ligands in its molecular structure have been designed, synthesized and characterized by CHN, Mass, 1H-NMR, UV-Vis, and fluorescence spectroscopies as well as cyclic voltammetry. Electrochemical and theoretical studies showed that the LUMO of the sensitizer is above TiO2 conduction band and the HOMO is below the redox potential of the electrolyte. This new sensitizer was tested in dye-sensitized solar cells using liquid redox couple (I-/I3-) and its performance was compared to the standard sensitizer N719.