Enhancing DSSC efficiency by 10.11 % through acid-base co-sensitization approach with thiazole-based organic dyes

This work focuses on the synthesis of novel organic sensitizers, ME-1 and ME-2, derived from thiazole compounds for application in dye-sensitized solar cells (DSSCs). We explored the photovoltaic performance of DSSCs using an innovative acid-based co-sensitization strategy. The co-sensitizers ME-1 (an acidic dye with a carbazole donor and rhodanine-3-acetic acid acceptor) and ME-2 (a basic dye with a pyridine acceptor) were combined with the Ru-based N3 dye to improve the DSSC efficiency. The most effective device performance was achieved by the acid-base co-sensitization system, which combined ME-2 and N3. This system achieved a power conversion efficiency of 10.11 %. The complementary absorption spectra of ME-2 and N3, along with their effective interaction with TiO2, enhanced light harvesting and minimized recombination losses. Electrochemical impedance spectroscopy (EIS) confirmed the superior charge transfer properties in the co-sensitized system, underscoring the role of acid-base interactions in boosting device performance. These results indicate that acid-base cosensitization is a promising method for optimizing DSSC efficiency by leveraging complementary dye characteristics to improve light absorption, charge separation, and electron transport.