Preparation of Electrolytic Quasi-Solid-State Nanofibers for Dye-Sensitized Solar Cells

Abstract

Nanofibers were prepared from a poly(acrylonitrile-co-vinyl acetate) [P(AN-co-VAC)]/polyvinylidene fluoride (PVDF) blend and used as a quasi-solid (QS) electrolyte for dye-sensitized solar cells (DSSCs). The effects of preparation parameters such as the flow rate and the weight percentage of PVDF on the fiber diameter, crystallinity, and ionic conductivity were investigated. Fourier-transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) were used to characterize the prepared blend nanofibers. Current–voltage and electrochemical impedance spectroscopy (EIS) measurements were carried out on the fabricated DSSCs. It was found that the optimum weight ratio of P(AN-co-VAC) to PVDF in N,N-dimethylformamide (DMF) to produce uniform fibers with average diameter of 180 nm was 7:3 with ionic conductivity (σi) of 2.9 × 10−3 S/cm. Moreover, the efficiency of DSSCs based on P(AN-co-VAC) as QS electrolyte was enhanced by 8.5 times by addition of PVDF. Finally, a model is proposed based on the EIS analysis.