New Ruthenium Sensitizer with Carbazole Antennas for Efficient and Stable Thin-Film Dye-Sensitized Solar Cells

A new heteroleptic ruthenium complex, coded CYC-B13, incorporating an antenna ligand composed of the sequential connection of a Conjugated segment and carbazole hole-transport moiety was prepared. This new sensitizer exhibits the lower energy MLCT band centered at 547 rim with a high molar absorption coefficient of 1.93 x 10(4) M-1 cm(-1). Thin-film cells based on this new sensitizer show good conversion efficiency (>8%) and excellent durability under light soaking at 60 degrees C in simulated sunlight for 1000 h. An all-solid state device based on CYC-B13 is also demonstrated to have a conversion efficiency of 3.8%. The photovoltaic data of DSCs sensitized with CYC-B13 suggested that carbazole is a photostable hole-transporting moiety to be used in dye-sensitized solar cells.