Solar Energy Materials and Solar Cells, Vol.94, No.4, 675-679, 2010
Effects of crown ethers in nanocomposite silica-gel electrolytes on the performance of quasi-solid-state dye-sensitized solar cells
The effects of crown ethers (CEs) on the performance of quasi-solid-state dye-sensitized solar cells (DSSCs) have been investigated. Nanocornposite silica was used to form gel matrices in the electrolytes, which contained lithium iodide (Lil) and iodine (I(2)) in 3-methoxypropionitrile (MPN) solvent. Three types of CEs, 12-crown-4 (12-C-4), 15-crown-5 (15-C-5), and 18-crown-6 (18-C-6) were used as additives to the gel electrolytes. DSSCs containing CEs showed enhancements in solar-to-electricity conversion efficiencies (eta), with reference to the one without them. The crown ether, 15-C-5, with a size of cavity matching with the size of Li(+) in the electrolyte rendered for its DSSC the best performance with an eta of 3.60%, under 100 mW/cm(2) illumination, as compared to 2.44% for the cell without any CE. Enhancements in the photovoltaic parameters of the cells with the CEs were explained based on the binding abilities of the CEs with lithium ions (Li(+)) in the electrolyte. Linear sweep voltammetry (LSV) measurements and electrochemical impedance spectra were used to substantiate the explanations. (C) 2009 Elsevier B.V. All rights reserved.
Keywords:Conductive pathway;Crown ether;Nanocomposite silica;Quasi-solid-state dye-sensitized solar cell;Radius of cavity