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Item New carbazole-based symmetric double D–A type chromophores for DSSC application: Impact of di-anchoring nature on photoelectrochemical processes(Elsevier B.V., 2025) Keremane, K.S.; Eletmany, M.R.; Abdellah, I.M.; Naik, P.; Vasudeva Adhikari, A.V.Herein, we report the systematic molecular design, synthesis, and characterization of a new series of carbazole-based organic dyes with a symmetric double donor–acceptor configuration, bearing seven different acceptor units as potential photosensitizers. The new molecules consist of strong electron-donating carbazole twin molecules linked together by a linear alkyl chain (C5H10) and attached to the various anchoring units, viz. cyanoacetic acid (DCP1), rhodanine-3-acetic acid (DCP2), rhodanine (DCP3), 1,3-dimethylbarbituric acid (DCP4), barbituric acid (DCP5), 1,3-diethyl-2-thiobarbituric acid (DCP6), and 4-nitrophenyl acetonitrile (DCP7). We performed structural, photophysical, thermal, electrochemical, and theoretical studies to assess the role of the dual anchoring nature of the chromophores on photoelectrochemical processes and their suitability as photosensitizers. The optical results revealed that all the dyes display ?abs and ?emi in the 404–465 nm and 503–556 nm range, respectively, with a bandgap of 2.44–2.70 eV. Furthermore, we have successfully fabricated new Dye-Sensitized Solar Cells (DSSCs) using dyes DCP1–7 as photosensitizers. Among them, DCP1 achieved the power conversion efficiency (PCE) of ?2 % under standard AM 1.5 solar conditions. Also, electrochemical impedance spectroscopy (EIS) has been carried out to investigate electronic and ionic processes within the cell. Conclusively, these studies showcase the significant potential of carbazole twin molecules with various anchoring units in improving the overall performance of DSSCs. © 2025 Elsevier B.V.Item Enhancing the Photoelectrochemical Performance of Ru(II)-Sensitized Dye-Sensitized Solar Cells Using Cyanopyridine-Based Cosensitizers(John Wiley and Sons Inc, 2025) Naik, P.; Abdellah, I.M.; Abdel-Shakour, M.; Keremane, K.S.; Vasudeva Adhikari, A.V.The cosensitization approach is one of the widely adopted strategies for systematically enhancing photovoltaic performance of dye-sensitized solar cells (DSSCs) by utilizing two or more dyes with distinct absorption spectra. This method achieves panchromatic absorption, improves intramolecular charge transfer performance, prevents dye aggregation, and increases dye loading capability. In this study, we investigated four previously reported push–pull-type dianchored chromophores (CP1–4) featuring a cyanopyridine scaffold as cosensitizer to enhance the performance of Ru(II)-based N3-sensitized DSSCs. Both the co-sensitized devices (N3 + CP1–4) and the N3-only devices were fabricated using a fixed dye concentration of 0.2 mM for each sensitizer/cosensitizers, while the coadsorbent chenodeoxycholic acid (CDCA) was systematically varied between 0 and 20 mM. This systematic variation of CDCA concentration was designed to examine its role in suppressing dye aggregation and modulating interfacial charge dynamics. Among the Series, CP4, carrying a thiobarbituric acid anchoring/acceptor group, demonstrated superior performance at all CDCA concentrations, achieving power conversion efficiency of 6.67%, 6.79%, and 5.74%, compared to 6.02%, 6.10%, and 5.44% for devices sensitized with N3 alone. Further, electrochemical impedance spectroscopy measurements confirmed the improved charge transport and reduced recombination in these devices. These findings highlight the potential of rationally engineered cosensitizers and optimized coadsorbent concentrations for enhancing the performance of metal-based sensitizers in DSSCs. © 2025 Wiley-VCH GmbH.