Solid oxide fuel cell anode materials

Tao SW, Irvine JTS (2004) Catalytic properties of the perovskite oxide Lao.75Sro.25Cro.5Feo.503 in relation to its potential as a solid oxide fuel cell anode material. Chem Mater 16 4116-4121... 

Tao, S. and Irvine, J. T. S. A Redox-Stable Efficient Anode for Solid-oxide Fuel Cells, Nature Materials, 2, 320 (2003). 

Gorte R J etal, 2000, Anodes for Direct Oxidation of Dry Hydrocarbons in a Solid Oxide Fuel Cell. Advanced Materials, doi.wiley.com. 

Wilson, J. R. et al. Three-dimensional reconstruction of a solid-oxide fuel-cell anode. Nature Materials 5, 541-544, doi 10.1038/nmatl668 (2006). 

J. R. Wilson, W. Kobsiriphat, R. Mendoza, H. Y. Chen, J. M. Hiller, D. J. Miller, K. Thornton, P. W. Voorhees, S. B. Adler, and S. A. Barnett. Three-dimensional reconstruction of a solid-oxide fuel-cell anode. Nature materials 5, (2006) 541-544. 

S. Tao and J. T. Irvine. A redox-stable efficient anode for solid-oxide fuel cells. Nature materials 2, (2003) 320-323. 

This reaction is of great technological interest in the area of solid oxide fuel cells (SOFC) since it is catalyzed by the Ni surface of the Ni-stabilized Zr02 cermet used as the anode material in power-producing SOFC units.60,61 The ability of SOFC units to reform methane "internally", i.e. in the anode compartment, permits the direct use of methane or natural gas as the fuel, without a separate external reformer, and thus constitutes a significant advantage of SOFC in relation to low temperature fuel cells. 

This presentation reports some studies on the materials and catalysis for solid oxide fuel cell (SOFC) in the author s laboratory and tries to offer some thoughts on related problems. The basic materials of SOFC are cathode, electrolyte, and anode materials, which are composed to form the membrane-electrode assembly, which then forms the unit cell for test. The cathode material is most important in the sense that most polarization is within the cathode layer. The electrolyte membrane should be as thin as possible and also posses as high an oxygen-ion conductivity as possible. The anode material should be able to deal with the carbon deposition problem especially when methane is used as the fuel. 

There has been considerable interest in Ce02 as a component of solid oxide fuel cells, especially as an anode material, and also for use in oxygen separation membranes. The material shows a wide nonstoichiometry range, with oxygen vacancies as the... 

Summary of Previous Studies on Potential Sulfur-Tolerant Anode Materials for Solid Oxide Fuel Cells... 

Zhu WZ and Deevi SC. A review on the status of anode materials for solid oxide fuel cells. Mater Sci Eng 2003 A362 228-239. 

Jiang SP and Chan SH. A review on anode materials development in solid oxide fuel cells. J Mater Sci 2004 39 4405 1439. 

Gong M, Liu X, Trembly J, and Johnson C. Sulfur-tolerant anode materials for solid oxide fuel cell application. J Power Sources 2007 168 289-298. 

Mai A, HaanappelVAC, UhlenbruckS, TietzF, and Stover D. Ferrite-based perovskites as cathode materials for anode-supported solid oxide fuel cells, Part I. Variation of composition. Solid State Ionics 2006 176 1341-1350. 

Yates C and Winnick J. Anode materials for a hydrogen sulfide solid oxide fuel cell. J Electrochem Soc 1999 146 2841-2844. 

Huang Y-H, Dass RI, Xing Z-L, and Goodenough JB. Double perovskites as anode materials for solid oxide fuel cells. Science 2006 312 254—256. 

Cheng, Z, Zha, S, and Liu, M. Stability of materials as candidates for sulfur-resistant anode of solid oxide fuel cells, J Electrochem Soc, 2006 153 A1302-A1309. 

Lu XC and Zhu JH. Ni-Fe + SDC composite as anode material for intermediate temperature solid oxide fuel cell. J. Power Sources 2007 165 678-684. 

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. 

Huang, K.G. et al.. Increasing power density of LSGM-based solid oxide fuel cells using new anode materials, J. Electrochem. Soc., 148, A788-A794 (2001). 

Setoguchi, T. et al., Effects of anode materials and fuel on anodic reaction of solid oxide fuel-cells,/. Electrochem. Soc., 139, 2875-2880 (1993). 

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