Anomaly of charge transport of an iodide/tri-iodide redox couple in an ionic liquid and its importance in dye-sensitized solar cells.

Fast charge transport based on the exchange reaction of an I(-)/I(3)(-) redox couple, which has been observed in ionic liquids due to their high ionic strength but not in molecular liquids, contributes to the high performance of dye-sensitized solar cells using the ionic liquids in spite of their high viscosity.