Synthesis of benzimidazole moiety heteroleptic ruthenium complex and use as sensitizer in dye-sensitized solar cells

The new benzimidazole functional heteroleptic ruthenium complex dye (BRD) was prepared for dye-sensitized solar cells (DSSCs). The compound was identified by various spectroscopic techniques and photovoltaic performances of this BRD DSSC were investigated and compared with Z907 (cis-diisothiocyanato-(2,2′-bipyridyl-4,4′-dicarboxylic acid)-(2,2′-bipyridyl-4,4′-dinonyl) ruthenium(II)) DSSCs. It was found that [Ruthenium (4,4′-dicarboxylic acid-2,2′-bipyridine) (1-(2-ethoxyethyl)-2-(pyridine-2-yl)benzimidazole) (NCS)2] (2) has a thermal stability below 300 °C. Two different electrolytes were used to get the effect on photovoltaic parameters. The photovoltaic measurements of the BRD and Z907 DSSCs were carried out under 100 mW/cm2 (AM1.5) illumination. Short-circuit current density (Jsc) values were obtained as 8.20 and 7.32 mA/cm2 for AN50 and HI30 electrolytes, respectively. The photovoltaic efficiencies were obtained as 3.03% and 2.82% for AN50 and HI30 electrolytes, respectively.