Electropolymerized-pani as DSSC counter electrode with low-cost with ionic liquids electrolyte

The in-situ electropolymerized-polyaniline(PANI) film (10 μm thickness) on FTO (fluorine tin oxide) glass doped by SO₄^2- was prepared, and its electropolymerizaion process was characterized by cyclic voltammetry. SEM of electropolymerized-PANI films doped by SO₄^2- exhibit porous and crude film morphology, and the porous film structures may be favorable for the high surface area porous counter electrode. The electrolytes composed of two binary ionic liquids 1-propyl-3-methylimidazolium iodide (PMII) and [EMIm]BF₄, [EMIm]N(CN)₂, [EMIm]NTf₂ in different ratio (volume/volume) were prepared. The results show that the electrolyte ([EMIm]N(CN)₂:PMII was 4:6) gave the best photovoltaic parameters: short-circuit photocurrent density J_sc=10.4 mA·cm^-2, open-circuit voltage V_oc=0.655 V, fill factor FF=0.521 and an overall energy conversion efficiency η=3.56% when the electrolytes was applied to the dye-sensitized solar cell (DSSC) with a electropolymerized-PANI electrode. On the other hand, the conductivity and apparent diffusion of I₃^- and I^- ions of electrolytes for DSSC were also measured. The electrolyte ([EMIm]N(CN)₂:PMII was 4:6) possessed of the highest conductivity and apparent diffusion of I₃^- and I^-.