Efficient Ruthenium Sensitizer with a Terpyridine Ligand Having a Hexylthiophene Unit for Dye-Sensitized Solar Cells: Effects of the Substituent Position on the Solar Cell Performance

A novel ruthenium sensitizer with a terpyridine ligand having a hexylthiophene unit at the 4‐position (TUS‐38) has been synthesized to investigate the effects of the substituent position on the photo‐ and electrochemical properties and on solar cell performance. The dye‐sensitized solar cell (DSC) with TUS‐38 showed a 10.6 % conversion efficiency under AM 1.5 (100 mW/cm2) irradiation, which is much higher than that of the DSC with a previously reported ruthenium sensitizer with a terpyridine ligand having two hexylthiophene units at the 5‐ and 5″‐positions. A novel ruthenium sensitizer with a terpyridine ligand having a hexylthiophene unit at the 4‐position (TUS‐38) has been synthesized, and the dye‐sensitized solar cell with TUS‐38 showed a 10.6 % conversion efficiency under AM 1.5 (100 mW/cm2) irradiation.