Three new tris-heteroleptic complexes of ruthenium(II) were designed by coordinating the metal center with cyclometalating, anchoring, and auxiliary ligands with different donor substituents. N-Hexylcarbazole, N-hexylphenothiazine, and N-hexyldiphenylamine donor moieties were used as substituents on the auxiliary ligands for SA633, SA634, and SA635, respectively. Complexes were characterized by H-1 and C-13 2D-COSY NMR techniques. These complexes provide power conversion efficiencies in the range of 7.6-8.2% when they are employed in state of the art dye-sensitized solar cells (DSCs) with cobalt electrolyte. Various electrochemical and transient techniques were used to unveil the unexpected differences in the performance of these very similar sensitizers.
Mohammad Khaja Nazeeruddin, Anurag Roy
Shaik Mohammed Zakeeruddin, Rosario Scopelliti, Jacques-Edouard Moser, Ulf Anders Hagfeldt, Joël Teuscher, Yasemin Saygili, Hui-Seon Kim, Marina Freitag, Marko Stojanovic