Triphenylamine-Based Dyes Bearing Functionalized 3,4-Propylenedioxythiophene Linkers with Enhanced Performance for Dye-Sensitized Solar Cells

Introduction of modified 3,4-propylenedioxythiophene units into triphenylamine-based dyes is found to enhance light capturing, suppress dye aggregation, and remarkably retard charge recombination in dye-sensitized solar cells. Open circuit voltages of the as-synthesized dyes (∼800 mV) are much higher than that with a thiophene congener (720 mV) under similar conditions as a result of self-passivation benefiting from their three-dimensional branched structures.