Solid oxide fuel cell method

Modeling Solid Oxide Fuel Cells Methods, Procedures and Techniques R. Bove and S. Ubertini, eds. 

The tape-casting method makes possible the fabrication of films in the region of several hundred micrometers thick. The mechanical strength allows the use of such a solid electrolyte as the structural element for devices such as the high-temperature solid oxide fuel cell in which zirconia-based solid electrolytes are employed both as electrolyte and as mechanical separator of the electrodes. 

Pratihar SK, Baus RN, Mazumder S, and Maiti HS. Electrical conductivity and microstructure of Ni-YSZ anode prepared by liquid dispersion method. In Singhal SC, Dokiya M, editors. Proceedings of the Sixth International Symposium on Solid Oxide Fuel cells (SOFC-VI), Pennington, NJ The Electrochemical Society, 1999 99(19) 513-521. 

R. Loehman et al., Development of Reliable Methods for Sealing Solid Oxide Fuel Cell Stacks, SECA Core Technology Program Review, January 27-28, 2005, Tampa,... 

Wang Z, Qian J, Cao J, Wang S, and Wen TJ. A study of multilayer tape casting method for anode-supported planar type solid oxide fuel cells (SOFCs). J. Alloys Compounds 2007 437 264—268. 

Pederson LR, Singh P, and Zhou XD. Application of vacuum deposition methods to solid oxide fuel cells. Vacuum 2006 80 1066-1083. 

Equally important are structural changes on the micrometer and the millimeter length scales, and eventually real reactors on a centimeter or even meter scale. In the first cases, full-field XAS is a well-matched method for in situ monitoring [6, 13, 25], An illustrative example is the catalytic partial oxidation (CPO) of methane to synthesis gas, a relevant reaction in the future s solid-oxide fuel cells. In Figure 4.3.4, it was... 

The redox properties of ceria-zirconia mixed oxides are interesting, because these materials find applications as electrolytes for solid oxide fuel cells, supports for catalysts for H2 production, and components in three-way automobile exhaust conversion catalysts. The group of Kaspar and Fornasiero (Montini et al., 2004, 2005) used TPR/TPO-Raman spectroscopy to identify the structural features of more easily reducible zirconia-ceria oxides and the best method for their preparation by suitable treatments. TPR/TPO experiments and Raman spectra recorded during redox cycles demonstrated that a pyrochlore-type cation ordering in Ce2Zr2Og facilitates low temperature reduction. 

Kurumada, M., Ito, A., and Fujie, Y, Preparation of La2-xSrxGaQ gMgQ jOj.j electrolyte for solid oxide fuel cell by citrate method using industrial raw materials, J. Ceram. Soc. Jpn., Ill, 200-204 (2003). 

Windes, W.E. and Lessing, P.A., Fabrication Methods of a Leaky SOFC Design, paper presented at the Eighth International Symposium of Solid Oxide Fuel Cells (SOFC VIII), 203rd Meeting of the Electrochemical Society, Paris, April 27-May 2, 2003. 

Jiang, S.P., A review of wet impregnation an alternative method for the fabrication of high performance and nano-structured electrodes of solid oxide fuel cells. Materials Science and Engineering A Structural Materials Properties Microstructure and Processing, 2006, 418, 199-210. 

Pale yellow cerium dioxide (ceria, ceric oxide) has the fluorite structure and is used in catalysis" ", solid oxide fuel cells (SOFC)", thin film optical waveguides" , reversible oxygen storage materials for automobile catalysts" and for doping copper oxide superconductors". The diverse cerium enolate precursors and deposition methods used in the formation of cerium oxide thin films are summarized in Table 6, whereby the most common precursor for ceria is Ce(thd)4. 

Another Ni-based solid oxide fuel cell (SOFC) electrode was developed on which a YSZ (yttria-stabilized zirconia) cermet and Lanthanum chromite were deposited by a slurry coating method. It was also suggested that a plasma spraying process can be used for the cermet deposition on the electrodes. The following reactions are expected to take place in a fuel cell employing a natural gas source, where internal reforming takes place on the Ni-YSZ electrode ... 

EXPLORATION OF COMBUSTION CVD METHOD FOR YSZ THIN FILM ELECTROLYTE OF SOLID OXIDE FUEL CELLS... 

The main component of a solid oxide fuel cell is a three-layered sandwich consisting of anode, electrolyte, and cathode, each being made from a different oxide ceramic material. Such ceramic structures can be fabricated by various methods including slip or tape casting, injection molding, ceramic coverings, etc. [1]. Whatever the method applied is, it should provide the best able microstructure and specified performance of materials besides the desired shape of a SOFC membrane. However, layers of the membrane have different properties that requires combination of two or more different methods of ceramic engineering in the component fabrication. 

Decreasing operation temperature of solid oxide fuel cells (SOFCs) and electrocatalytic reactors down to 800-1100 K requires developments of novel materials for electrodes and catalytic layers, applied onto the surface of solid electrolyte or mixed conducting membranes, with a high performance at reduced temperatures. Highly-dispersed active oxide powders can be prepared and deposited using various techniques, such as spray pyrolysis, sol-gel method, co-precipitation, electron beam deposition etc. However, most of these methods are relatively expensive or based on the use of complex equipment. This makes it necessary to search for alternative synthesis and porous-layer processing routes, enabling to decrease the costs of electrochemical cells. Recently, one synthesis technique based on the use... 

Since complicated multicomponent ceramic materials with precise levels of doping are required for some of the new materials that show promise in solid oxide fuel cells, we aim to use the relatively low-cost, simple steric entrapment method to synthesize several solid oxide fuel cell materials, and evaluate some of their characteristics. We have selected lanthanum gallates doped with strontium and magnesium, samarium doped ceria and a promising non-stoichoimetric composition composed of strontium iron and cobalt. 

Using steric entrapment, solid oxide fuel cell materials were successfully produced by an aqueous synthesis method. The powders were more homogeneous and required lower processing temperatures than did powders made by more conventional methods. Properties of the powder and sintered microstructures were comparable with those properties attained using more complex methods such as sol-gel and with less organics than methods such as the glycine-nitrate method. Further work is needed to fully optimize the PVA to cation ratio to produce the most favorable powder characteristics. 

Rosczyk B.R., Kriven W.M., Mason T.O., Solid oxide fuel cell materials synthesized by an organic steric entrapment method, 2003, V.24, N.3, p.287-292. 

---