Dithiafulvenyl-equipped Ru(II) bis-terpyridine complexes – Synthesis, photophysical and electrochemical properties

Dithiafulvalenes (DTFs) represent an important class of organic dyes known for their redox-activity and ability to oxidatively dimerize into tetrathiafulvalene vinylogues (TTFVs). These systems, in turn, exhibit a reversible redox-driven conformational switching between a charge neutral cisoid and a dicationic transoid form. Both types of dyes have already been utilized, as organic sensitizers, in dye-sensitized solar cells (DSSCs). A series of DTF- and TTFV-bearing Ru(II) bis-terpyridyl complexes has been prepared and characterized with respect to their photophysical and electrochemical properties. A fundamental study of the model complexes is presented and is of importance for a later incorporation of such chromophores, as sensitizers, into DSSCs.