Table of Contents Author Guidelines Submit a Manuscript
International Journal of Photoenergy
Volume 2012, Article ID 671326, 7 pages
http://dx.doi.org/10.1155/2012/671326
Research Article

Electrochemically Deposited Polypyrrole for Dye-Sensitized Solar Cell Counter Electrodes

1Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand
2College of Nanotechnology, King Mongkut’s Institute of Technology Ladkrabang, Chalongkrung Road, Ladkrabang, Bangkok 10520, Thailand

Received 1 July 2011; Accepted 6 October 2011

Academic Editor: Shahed Khan

Copyright © 2012 Khamsone Keothongkham et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Polypyrrole films were coated on conductive glass by electrochemical deposition (alternative current or direct current process). They were then used as the dye-sensitized solar cell counter electrodes. Scanning electron microscopy revealed that polypyrrole forms a nanoparticle-like structure on the conductive glass. The amount of deposited polypyrrole (or film thickness) increased with the deposition duration, and the performance of polypyrrole based-dye-sensitized solar cells is dependant upon polymer thickness. The highest efficiency of alternative current and direct current polypyrrole based-dye-sensitized solar cells (DSSCs) is 4.72% and 4.02%, respectively. Electrochemical impedance spectroscopy suggests that the superior performance of alternative current polypyrrole solar cells is due to their lower charge-transfer resistance between counter electrode and electrolyte. The large charge-transfer resistance of direct current solar cells is attributed to the formation of unbounded polypyrrole chains minimizing the reduction rate.