Application of π-extended ferrocene with varied anchoring groups as photosensitizers in TiO2-based dye-sensitized solar cells (DSSCs)

Two new compounds, FcCH=NC(6)H(4)COOH (1) and FcCH=NCH(2)CH(2)OH (2) (Fc=C(5)H(4)FeC(5)H(5)), have been synthesized and characterized by elemental analyses, IR and (1)H NMR spectroscopy, and ESI-MS. Attempt has been made to explain their quasi-reversible redox behavior evidenced by cyclic voltammetry using density functional theory (DFT) calculations. Light-harvesting properties of both the compounds and also the starting material, FcCHO (3), have been studied using these compounds as photosensitizers in TiO(2)-based dye-sensitized solar cells having either a propylene carbonate-based electrolyte or ionic liquid electrolyte, namely, 1-propyl-3-methyl imidazolium iodide (PMII). Long-term stability of the photocurrent output of the cell using compound 1 as photosensitizer has been monitored periodically over 1400 h.