Novel biopolymer gel electrolyte for dye-sensitized solar cell application

We report a new biopolymer electrolyte for dye sensitized solar cell application. To develop polymer electrolyte, potassium iodide have been added in agarose biopolymer matrix and characterized using various techniques like complex impedance spectroscopy, Infrared spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM). Complex impedance spectroscopy shows many folds enhancement in ionic conductivity (sigma) by salt doping and conductivity maxima was obtained near 60:40 composition. Infrared spectroscopy confirms the formation of composite nature. XRD revels the reduction of crystallinity by salt doping as well affirms the composite nature. Scanning electron microscopy (SEM) shows reduction in crystallinity of gel matrix by salt doping which is a known favorable condition for ionic conductivity enhancement. To further affirm the conductivity enhancement in the gel electrolyte system a theoretical hopping model is also described in details. A DSSC has been developed using maximum electrical conductivity film which shows 0.54% efficiency at 1 sun condition. (C) 2012 Elsevier Ltd. All rights reserved.