Enhanced photovoltaic performances of quasi-solid-state dye-sensitized solar cells using a novel conducting gel electrolyte

The extension of electrocatalytic reaction area toward iodides is expected to significantly accelerate the recovery of redox couples and therefore photovoltaic performances of quasi-solid-state dye-sensitized solar cells (DSSCs). To improve the cell properties of DSSC, a three-dimensional polypyrrole imbibed poly(hydroxyethyl acrylate)/poly(ethylene glycol) gel electrolyte has been successfully synthesized using the adsorption behavior of amphiphilic poly(hydroxyethyl acrylate)/poly(ethylene glycol) to pyrrole monomers. Resultant gel electrolyte is thoroughly characterized by spectral analysis and electrochemical characterizations. In comparison with pure poly(hydroxyethyl acrylate)/poly(ethylene glycol) gel electrolyte, the incorporation of electron-conducting polypyrrole shows enhanced physicochemical properties. Interconnected micropores within the gel electrolyte provides space for holding I-/I-3(-) liquid electrolyte, giving an ionic conductivity of 21.08 mS cm(-1). The integration of polypyrrole on poly(hydroxyethyl acrylate)/poly(ethylene glycol) gives a higher electrocatalytic activity because of the extension of electrocatalytic reaction toward I-/I-3(-) couple from counter electrode/gel electrolyte interface to the three-dimensional framework of gel electrolyte. The resultant DSSC from polypyrrole imbibed poly(hydroxyethyl acrylate)/poly(ethylene glycol) gel electrolyte displays a light-to-electric conversion efficiency of 7.02% in comparison with 5.76% from pure poly(hydroxyethyl acrylate)/poly(ethylene glycol). The new concept along with easy fabrication promise the conducting polymer imbibed amphiphilic gel electrolytes good candidates in robust DSSCs. (C) 2013 Elsevier B.V. All rights reserved.