Solid oxide fuel cells metallic

Solid oxide fuel cells consist of solid electrolytes held between metallic or oxide elecU odes. The most successful fuel cell utilizing an oxide electrolyte to date employs Zr02 containing a few mole per cent of yttrium oxide, which operates in tire temperature range 1100-1300 K. Other electrolytes based... 

High-temperature solid-oxide fuel cells (SOFCs). The working electrolyte is a solid electrolyte based on zirconium dioxide doped with oxides of yttrium and other metals the working temperatures are 800 to 1000°C. Experimental plants with a power of up to lOOkW have been built with such systems in the United States and Japan. 

Although the superconducting state of this material has attracted considerable attention, the metallic state is also of interest. For instance, metallic samples are being explored for use as cathode materials in solid oxide fuel cells (Section 6.10). 

Corbin SF and Qiao X. Development of solid oxide fuel cell anodes using metal-coated pore-forming agents. J Am Ceram Soc 2003 86 401-406. 

Fergus JW. Metallic interconnects for solid oxide fuel cells. Mater. Sci. Eng. A 2005 A397 271-283. 

Mori M, Yamamoto T, Itoh H, and Watanabe T. Compatibility of alkaline earth metal (Mg,Ca,Sr)-doped lanthanum chromites as separators in planar-type high-temperature solid oxide fuel cells. J. Mater. Sci. 1997 32 2423-2431. 

M. Bram et al., Basic investigations on metallic and composite gaskets for an application in SOFC stacks, in Proceedings of the Fifth European Solid Oxide Fuel Cell Forum, J. Huijsmans (ed.), 1-5 July 2002, Lucerne, Switzerland, 2202, pp. 847-854. 

Villarreal I, Jacobson C, Leming A, Matus Y, Visco S, and De Jonghe L. Metal-supported solid oxide fuel cells. Electrochem. Solid State Lett. 2003 6 A178-A179. 

Xie Y, Neagu R, Hsu CS, Zhang X, and Deces-Petit C. Spray pyrolysis deposition of electrolyte and anode for metal-supported solid oxide fuel cell. J. Electrochem. Soc. 2008 155 B407-B410. 

M. Mamak, N. Coombs, and G. Ozin, Self-assembling solid-oxide fuel cell materials mesoporous yttria-zirconia and metal—yttria-zirconia solid solutions, J. Am. CherrL Soc. 122, 8932-8939 (2000). 

Tubular Solid Oxide Fuel Cell (TSOFC) The electrolyte in this fuel cell is a solid, nonporous metal oxide, usually Y203-stabilized Z1O2. The cell operates at 1000°C where ionic conduction by oxygen ions takes place. Typically, the anode is Co-Zr02 or Ni-Zr02 cermet, and the cathode is Sr-doped LaMnOs. 

It has been observed that solid oxide fuel cell voltage losses are dominated by ohmic polarization and that the most significant contribution to the ohmic polarization is the interfacial resistance between the anode and the electrolyte (23). This interfacial resistance is dependent on nickel distribution in the anode. A process has been developed, PMSS (pyrolysis of metallic soap slurry), where NiO particles are surrounded by thin films or fine precipitates of yttria stabilized zirconia (YSZ) to improve nickel dispersion to strengthen adhesion of the anode to the YSZ electrolyte. This may help relieve the mismatch in thermal expansion between the anode and the electrolyte. 

Dr. Hui has worked on various projects, including chemical sensors, solid oxide fuel cells, magnetic materials, gas separation membranes, nanostruc-tured materials, thin film fabrication, and protective coatings for metals. He has more than 80 research publications, one worldwide patent, and one U.S. patent (pending). He is currently leading and involved in several projects for the development of metal-supported solid oxide fuel cells (SOFCs), ceramic nanomaterials as catalyst supports for high-temperature PEM fuel cells, protective ceramic coatings on metallic substrates, ceramic electrode materials for batteries, and ceramic proton conductors. Dr. Hui is also an active member of the Electrochemical Society and the American Ceramic Society. 

A solid oxide fuel cell (SOFC) consists of two electrodes anode and cathode, with a ceramic electrolyte between that transfers oxygen ions. A SOFC typically operates at a temperature between 700 and 1000 °C. at which temperature the ceramic electrolyte begins to exhibit sufficient ionic conductivity. This high operating temperature also accelerates electrochemical reactions therefore, a SOFC does not require precious metal catalysts to promote the reactions. More abundant materials such as nickel have sufficient catalytic activity to be used as SOFC electrodes. In addition, the SOFC is more fuel-flexible than other types of fuel cells, and reforming of hydrocarbon fuels can be performed inside the cell. This allows use of conventional hydrocarbon fuels in a SOFC without an external reformer. 

For example, the electrolyte of alkali fuel cells is a solution of potassium hydroxide (an alkaline, which has a high pH). Solid oxide fuel cells use compoimds of metal oxides as electrolytes. (Fuel cell names are generally... 

It must be remembered that in aqueous systems the redox process occurs over the entire electrode area, whereas in solid electrolyte systems the redox process occurs only in the three-phase or charge-transfer region. The technique has been used with solid electrolyte systems for sometime to study the oxidation and reduction of metals and metal oxides in inert atmospheres,94,95 the behaviour of solid oxide fuel cell (SOFC) electrodes and has also been applied to the in-situ study of catalysts.31,32,95... 

Experimental solid-oxide fuel cells that use butane (C4H10) as the fuel have been reported recently. These cells contain composite metal/metal oxide electrodes and a solid metal oxide electrolyte. The cell half-reactions are... 

Quadakkers W.J., Piron-Abellan J., Shemet V., Singheiser L. (2003) Metallic interconnectors for solid oxide fuel cells - A review. Mater. High Temp. 20(2), 115-127. 

Tucker MC. Progress in metal-supported solid oxide fuel cells A review. Journal of Power Sources. 2010 195(15) 4570-4582. 

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