Optimization of performance characteristics of 2-mercaptopyridine-doped polyvinylidene fluoride (PVDF) polymer electrolytes for dye-sensitized solar cells

The influence of 2-mercaptopyridine on the ionic conductivity of polyvinylidene fluoride/KI/I2 polymer electrolyte for dye-sensitized solar cells was studied. Different weight ratios (0%, 20%, 30%, 40% and 50%) of 2-mercaptopyridine-doped polyvinylidene fluoride/KI/I2 polymer electrolyte films were prepared by solution casting method. The as-prepared polymer electrolyte films were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, electrochemical impedance analysis and X-ray diffraction. Ionic conductivity studies revealed that 30% 2-mercaptopyridine-doped polyvinylidene fluoride/KI/I2 polymer electrolyte showed the highest ionic conductivity of 4.58 × 10− 5 Scm− 1. The conversion efficiency of dye-sensitized solar cell fabricated using this electrolyte was 2.65%, which was higher than that of undoped polyvinylidene fluoride/KI/I2 polymer electrolyte (1.18%) under an illumination of 60 mW/cm2. Hence, the 2-mercaptopyridine-doped polymer electrolyte can be a suitable material for device applications.