Isotruxene-Derived Cone-Shaped Organic Dyes for Dye-Sensitized Solar Cells

The synthesis, electronic properties, and performance in dye-sensitized solar cells (DSSCs) of four cone-shaped organic dyes (ITD, ITD-Th, ITD-Hx, and ITD-OM) containing the isotruxene pi-scaffold are reported Selective substitution of the unsymmetrical isotruxene core with two diarylamino donors and one cyanocarboxylic acid acceptor was achieved by using a prefunctionalized dibromoisotruxene building block The ortho-para-branched isotruxene core allows strong electronic couplings among the donors and the acceptor, leading to red-shifted absorption profiles with significant charge-transfer character All four isotruxene dyes display reversible anodic waves in cyclic voltammagrams with both HOMO and LUMO potentials suitable for application in DSSCs The DSSCs fabricated with these cone-shaped organic dyes exhibited high open-circuit voltages (0 67-0 76 V) and fill factors (0 67-0 72) with a power conversion efficiency (eta) up to 545%, which is 80% of the ruthenium dye N719-based standard cell fabricated and measured under the same conditions