An alternative methodology for anchoring organic sensitizers onto TiO2 semiconductors for photoelectrochemical applications

In the present work, we investigated alternative ways of connecting purely organic dyes onto the surface of TiO2 electrodes. For this purpose, perfluorophenyl ω-end rr-poly(3-alkyl thiophene)s were synthesized, which can react with the hydroxyl groups of TiO2 under mild alkaline conditions. Thus, stable non-hydrolysable Ti–O–C bonds are formed. Through this route, and after optimization of the reaction conditions, several poly(thiophene)-sensitized TiO2 photoanodes were prepared and tested in dye-sensitized solar cells. Moreover, a comparative study was performed for the dye/TiO2 stability after water and alkaline solution treatment revealing the particular methodology's efficiency. The above sensitizers have also proven to be functional in photoelectrochemical cells employed for water splitting applications in the presence of alkaline electrolytes.