A new ionic liquid based quasi-solid state electrolyte for dye-sensitized solar cells

Ionic liquid based quasi-solid state electrolytes were prepared by solidifying the ionic liquid electrolytes containing 1-hexyl-3-methylidazolium iodide (HMImI) or a binary mixture of HMImI and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4) with an ionic liquid polymer poly (1-oligo (ethylene glycol) methacrylate-3-methylimidazolium chloride) (P(MOEMImCl)), respectively. The improvements of the ionic conductivity and the apparent diffusion coefficient of triiodide are observed in the binary ionic liquid mixture gel electrolyte. The thermal stability of the quasi-solid state electrolytes is determined by thermogravimetric analysis. The ionic liquid based quasi-solid state electrolytes were successfully used to fabricate the dye-sensitized solar cells achieving the conversion efficiency of 6.1% under the light intensity of 100 mW cm−2.