Application of Diaminium Iodides in Binary Ionic Liquid Electrolytes for Dye-Sensitized Solar Cells
N-(2-hydroxyethyl)ethylenediaminium iodides (HEEDAIs) and N-(2-hydroxyethyl)piperazinium iodides (HEPIs) were synthesized, and their thermal properties were analysed. The influence of HEEDAI and HEPI onI3-/I-redox behavior in binary ionic liquid was investigated. The result revealed that HEEDAI can suppress the recombination betweenI3-and the injected electrons in TiO2conduction band and be used as the alternative of 4-tert-butylpyridine in the electrolyte of dye-sensitized solar cells. The electrolyte C, 0.15 mol⋅L−1I2, HEEDAI and MPII with mass ratio of 1 : 4, gave the short-circuit photocurrent density of 9.36 mA⋅cm−2, open-circuit photovoltage of 0.67 V, fill factor of 0.52, and the corresponding photoelectric conversion efficiency of 3.24% at the illumination (air mass 1.5, 100 mW⋅cm−2, active area 0.25 cm2).