Enhanced performance of dye-sensitized solar cell using 2-mercaptobenzothiazole-doped poly(vinylidinefluoride-co-hexafluoropropylene) polymer electrolyte

Abstract

The effect of 2-mercaptobenzothiazole (2-MCBT) on the performance of poly(vinylidinefluoride-co-hexafluoropropylene)/KI/I2 (PVDF-HFP/KI/I2) electrolyte in dye-sensitized solar cell (DSSC) was studied. The pure and 2-MCBT-doped PVDF-HFP/KI/I2 electrolytes were prepared by solution casting technique using N,N-dimethyl formamide (DMF) as a solvent. The characteristic properties of the as-prepared polymer electrolyte films were examined using various techniques such as Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometer (XRD), AC-impedance analysis, and scanning electron microscopy (SEM) analysis. The ionic conductivity of polymer electrolytes was determined using AC-impedance analysis. The room temperature ionic conductivity of pure and 2-MCBT-doped PVDF-HFP/KI/I2 electrolytes were found to be 7.08 × 10−6 and 5.96 × 10−5 Scm−1, respectively. The increase in ionic conductivity of 2-MCBT-doped electrolyte may be due to the increase of both amorphous nature and iodide ion mobility of the polymer electrolyte. The photovoltaic studies, using pure and 2-MCBT-doped PVDF-HFP/KI/I2 electrolyte in DSSC showed an increase of power conversion efficiency from 1.74 to 3.46 % under the light intensity of 60 mW/cm2. Thus, the 2-MCBT-doped polymer electrolyte has been found to be a suitable material for DSSC applications.