A comparative study of charge transport in quasi-solid state dye-sensitized solar cells using polymer or nanocomposite gel electrolytes

To improve the photovoltaic and durability performance of quasi-solid dye-sensitized solar cells (DSCs), we added selected gelators to the liquid electrolyte. Metal-oxide nanoparticles or fluorine polymers were employed to solidify 3-methoxypropionitrile-based liquid electrolytes containing an ionic liquid, 1,2-dimethyl-3-propyl imidazolium iodide, as a source of iodide. The electrochemical impedance spectroscopy and cyclic voltammetry were employed to study the kinetics of electrochemical and photoelectro-chemical processes, including the elucidation of the electronic and ionic processes occurring in the various quasi-solid-state solar cells. Among tested gelators, a cell with TiO2 solidified electrolyte (P25, 17.5 wt%) exhibited the best photovoltaic performance with power conversion efficiency 7.65% under simulated sunlight (100 mWcm(-2)). The DSCs with a TiO2 solidified electrolyte showed endurance of stability superior to that of a pure liquid electrolyte. (C) 2012 Elsevier BM. All rights reserved.