A Series of N-Alkylimidazolium Propylhexanamide Iodide for Dye-Sensitized Solar Cells

摘要

We report a series of novel imidazolium iodides based ionic liquids (NMTPHI, NAIPHI, and NBIPHI) with different functional groups for the development of a quasi-solid type electrolyte for dye-sensitized solar cells (DSSCs). The diffusion coefficients of redox ions (I~- and I3~-) are dependent on the molecular weight and it was higher for lighter salts. Among the three ionic liquids, NMTPHI showed highest efficiency of 4.18% when it was used in a liquid electrolyte of a DSSC with ca. 6 μm thick T1O2 mesoporous film. Even though the efficiency was ca. 19% lower than that obtained from a liquid electrolyte composed of PMTI. When NMIPHI was mixed with PMH with a molar ratio of 1:1 in a solvent free electrolyte, the efficiency of the DSSCs was enhanced compared to that based on pristine PMII.