A novel deep eutectic solvent-based ionic liquid used as electrolyte for dye-sensitized solar cells

We utilize a quaternary ammonium salt-derivative ionic liquid called G.CI which is a eutectic mixture of glycerol and choline iodide as electrolyte for dye-sensitized solar cells. Such eutectic compound belongs to a new series of ionic liquid called deep eutectic solvents (DES), which possess many outstanding features compared to the traditional imidazolium-based ionic liquids including cheap raw materials, simple preparation procedures and better biocompatibility. Current–voltage characteristics of the G.CI/PMII-based binary electrolytes stand at 0.533 V on V_oc, 12.0 mA cm^?2 on J_sc, 0.582 on fill factor, and 3.88% cell efficiency under AM 1.5, 100 mW/cm² illuminations. The comparable cell performance together with all the above advantages makes G.CI as a strong candidate for future electrolyte development for dye-sensitized solar cells (DSSCs).