Technical Proceedings of the 2008 Clean Technology Conference and Trade Show

Clean Technology 2008

Chapter 5: Fuel Cell & Hydrogen Technologies

A. Nicoara, V. Cosoveanu, I. Ladiu, L. Baia, M. Baia, L. Muresan, I. Stamatin, V. Danciu
Babes-Bolyai University cluj-Napoca, RO
298 - 301
zirconia aerogel, polyoxometalate composite, solid oxide fuel cell
Zirconia is based material with various applications in catalysis, oxygen sensors, SOFC and electrochemical pumps. Zirconia aerogels dopped or functionalized with solid heteropolyacids extend applications to high performances materials with improved features such as: high porosity, low-density, large surface area, oxidizing-reducing properties [1]. Combining high protonic conductivity at room temperature and high solubility, for polyoxometalates with zirconia aerogel can be successfully employed as electrolyte in H2/O2 fuel cells [2]. This contribution deal with ionic-conducting zirconia aerogels-heteropolyacids composites, synthesized by sol-gel method combined with supercritical drying. The composites were characterized using TG/DTA, BET, elemental analysis, FTIR and Raman spectroscopy. Conductivity was evaluated by EIS at different temperatures. Electrochemical behavior (powder incorporated in carbon paste) was investigated using cyclic voltammetry. Activation energy of the zirconia aerogel-polyxometalate is less 25-35 Kcal/mol [3] that proves high proton conduction. The results show Zirconia aerogel - H4SiW12O40 composites can be an alternative for medium temperature SOFC due to their high ionic conductivity. References [1] K.Tanabe, Mater. Chem. Phys., 347, 13 (1985) [2] N.Girdano, P. Staiti, S. Hocevar, A. S. Arico, Electrochim. Acta, 41, 397 (1996) [3] N. Sammes, A. Smirnova, O. Vasylyev, Fuel Cell Technologies: State and Perspectives, Springer, Dordrecht, 2005, p 37
Zirconia Aerogel-Polyxometalate Composites Synthesis with Applications in Solid Oxide/Acid Fuell Cells