Lanthanum Gallates

In the search for new oxygen ion conductors to be used as electrolytes in SOFCs, oxides have been extensively studied in recent years, which crystallize in the perovskite structure and in structures derived therefrom e.g. the brownmillerite 

The Gibbs energy of formation of LaGaOj has been determined using galvanic cells and vapour pressure measurements combined with a defect chemical analy-sis ),6 enthalpy of formation was determined by calorimetry.  

Suresh, S. Schlag and K. Yokose, Chemical Economics Handbook Report Air Separation Gases , SRI Consulting, Menlo Park, California, 2002. 

Downie, Industrial gases, Kluwer Academic, Dordrecht, 1997. 

Ruthven, S. Farooq and K. S. Knaebel, Pressure Swing Adsorption, VCH Publishers, New York, Weinheim, Cambridge, 1993. 

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G. Ch. Kostogloudis, Ch. Ftikos, A. Ahmad-Khanlou, A. Naoumidis, D. Stover, Chemical compatibility of alternative perovskite oxide SOFC cathodes with doped lanthanum gallate solid electrolyte , Solid State Ionics 134,127-138 (2000). 

A. Ctineyt Ta , Peter J. Majewski, Fritz Aldinger, Chemical preparation of pure and strontium- and/or magnesium-doped lanthanum gallate powders , Journal of American Ceramic Society 83[12], 2954-2960 (2000). 

Marko Hrovat, Ariane Ahmad-Khanlou, Zoran Samadzija, Janez Hole, Interactions between lanthanum gallate based solid electrolyte and ceria , Materials Research Bulletin, 34[12/13], 2027-2034 (1999). 

In this paper, we report the preparation of Sr- and Mn-doped lanthanum gallate powders (Lao.gSro.iGai.xMnxOs, x=0.2, 0.35, 0.43) by a glycine nitrate process. The electrical properties of sintered pellets from as-prepared powders at different atmospheres, as well as their chemical stability under H2 atmosphere were characterized. 

Figure 12 Conductivities of selected oxides as a function of temperature. Doped ceria and zirconia, and lanthanum gallate are oxide ion conductors, while hariiun zirconate is a proton conductor (From S.M. Haile Materials for fuel cells. Materials Today 6 24-29 (March 2003)). (Reprinted from Ref. 148. 2003, with permission from Elsevier)...

Maffei, N. and de Silveira, G., Interfacial layers in tape cast anoe-supported doped lanthanum gallate SOFC elements. Solid State Ionics, 159, 209-216 (2003). 

Kuroda, K. et al.. Characterization of solid oxide fuel cell using doped lanthanum gallate, So/tVfStofe 7o C5, 132, 199-208 (2000). 

Pengnian, H. et al.. Interfacial reaction between nickel oxide and lanthanum gallate during sintering and its effect on conductivity, J. Am. Ceram. Soc., 82, 2402-2406 (1999). 

Yan, J.W., Lu, Z.G., Jiang, Y., Dong, Y.L., Yu, C.Y., and Li, W.Z., Fabrication and testing of a doped lanthanum gallate electrolyte thin-film solid oxide fuel cell. Journal of the Electrochemical Society, 2002, 149, A1132-A1135. 

Lerch, M., Boysen, H., and Hansen, T., High-temperature neutron scattering investigation of pure and doped lanthanum gallate. Journal of Physics and Chemistry of Solids, 2001, 62, 445 55. 

Baskaran, S., Lewinsohn, C.A., Chou, Y.S., Qian, M., Stevenson, J.W., and Armstrong, T.R., Mechanical properties of alkaline earth-doped lanthanum gallate. Journal of Materials Science, 1999, 34, 3913-3922. 

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