Organic dyes end-capped with perfluorophenyl anchors: Synthesis, electrochemical properties and assessment of sensitization capacity of titania photoanodes

•Synthesis and characterization of carbazole-alt-benzothiadiazole molecular dyes.•Thienyl versus 3,4-ethylenedioxythiophene units.•Perfluorophenyl-anchors for TiO2 photoanodes sensitization via stable C-O-Ti bonds.•DSSCs and PEC applications.•Exact chemical structure's impact on properties and devices performances.

In the present work, organic sensitizers are synthesized and attached on TiO2 photoanodes via Ti-O-C bonds. All sensitizers, designed for this purpose are symmetrical and have two perfluorophenyl end groups, which can lead to stable non-hydrolysable bonds on the TiO2 surface. Broad absorption in the UV-Vis region and low band gap energy levels have been achieved through the alternation of carbazole- and benzothiadiazole-based units. All dyes and their corresponding photoanodes, were characterized via various complementary techniques, including Cyclic Voltammetry measurements and sensitization capacity in Dye-sensitized solar cell tests.

Graphical abstractTwo organic dye sensitizer families attached onto TiO2 photoanodes via non-hydrolysable C-O-Ti bonds are “fighting” over DSSCs and PCEs. Superiority of EDOT-bearing dyes is demonstrated.Download high-res image (246KB)Download full-size image