Doped Lanthanum Gallate

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. 

Huang, P., and Petrie, A. (1996). Superior oxygen ion conductivity of lanthanum gallate doped with strontium and magnesium. J Electrochem Soc. 143 1644-1648. 

The materials that have been studied the most are yttria stabilized zirconia, doped ceria with gadolinium and lanthanum gallate doped with strontium and magnesium. The solid oxide fuel cells can, in principle, operate in a wide temperature range between 500 °C and... 

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). 

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). 

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. 

The development of electrolytes that exhibit a higher conductivity at low temperature. Three candidates have emerged, namely doped ceria, doped lanthanum gallate, and doped barium zirconate. The first two of these are oxygen ion electrolytes, and the latter is a proton conductor. 

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