Solid state metal-free eosin-Y dye sensitized solar cell based on PVdF-HFP electrolytes: combined effect of surface modified TiO2 and plasticizer on electrochemical and photovoltaic properties

The hybrid polymer nanocomposites based on poly(vinylidene fluoride-co-hexaflouro propylene) (PVdF-HFP) as a host matrix, propylene carbonate as the plasticizer, and surface modified and unmodified TiO2 nanoparticles as fillers for dye-sensitized solar cell applications have been prepared using a solvent casting technique. The surface of TiO2 was modified using aminopropyltrimethoxysilane (APS), and its organic functional groups on TiO2 were confirmed by Fourier transform infrared (FTIR) spectroscopy. The PVdF-HFP membranes were characterized by FTIR, wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), atomic force microscopic (AFM), and ultraviolet–visible (UV-Vis) spectroscopic techniques. It was found a new interaction of APS molecules on TiO2 surface with matrix as well as electrolyte salt. The experimental observations indicated a noticeable improvement in ionic conductivity of modified TiO2 of about 6.7 × 10−4 S/cm when compared with unmodified counterpart (TiO2) as the filler within PVDF-HFP matrix. The solid state dye-sensitized solar cell has been fabricated by using silane-modified TiO2/PVdF-HFP nanocomposite electrolyte and eosin-Y as sensitizer, and its photoconversion efficiency is measured about 1.47 %.