Lanthanum gallate electrolytes

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. 

Feng, M., Goodenougb, J. B., Huang, K. Q., and Milliken, C. (2000). Fuel cells witb doped lanthanum gallate electrolyte./. Power Sources 63 47-63. 

T. Inagaki, F. Nishiwaki, S. Yamasaki, T. Akbay and K. Hosoi, Intermediate Temperature Solid Oxide Fuel Cell based on Lanthanum Gallate Electrolyte,/. Power Sources, 181,274-280(2008). 

Pena-Martinez J, Manero-Lopez D, Ruiz-Morales JC, Savaniu C, Nunez P, Irvine JTS (2006) Anodic performance and intermediate temperature fuel cell testing of Lao.75Sro.25Cro.5Mho.503 d at lanthanum gallate electrolytes. Chem Mater 18 1001-1006... 

The search for new materials for IT-SOFCs is currently a key activity. Ceria materials, as noted earlier, are more conductive than the traditional YSZ except that ceria is unstable at elevated temperatures in reducing atmospheres. Fortunately, if the temperature of operation is as low as 500°C, then the increased electronic conductivity caused by reduction of to Ce + ions is relatively low and then this issue appears not to be such a big concern (Steele, 2001). Lanthanum gallate electrolytes are also being investigated for IT-SOFC applications, and time will tell which material offers the best prospects, both technically and economically, for conunercial systems. 

Pena-Martinez, J., Tarancdn, A., Marrero-Ldpez, D., Ruiz-Morales, J.C., and Niinez, P. (2008) Evaluation of GdBaCo20s+a as cathode material for doped lanthanum gallate electrolyte IT-SOFCs. Fuel Cells. 8 (5), 351 359. 

In 1994, new solid electrolytes with high conductivity at low temperatures were found in the form of doped lanthanum gallates [142]. Since the selfdiffusion coefficients of cations are apparently fundamentally larger in the perovskite-type oxides than in fluorite oxides, lanthanum gallate electrolyte and associated electrode materials tend to react too easily at the temperatures of fabrication and operation of cells. 

J. Pena-Martinez, A. Tarancon, D. Marrero-Lopez, J.C. Ruiz-Morales, P. Nunez, Evaluation of GdBaCo205+ as Cathode Material for Doped Lanthanum Gallate Electrolyte IT-SOFCs. Fuel CeUs 8, 351-359 (2008)... 

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). 

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). 

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. 

Lanthanum gallate is doped with divalent metal ions, for instance, strontium and magnesium Lai jSrjMgyGai j,03 usually, x and y have values between 1 and 0. Unlike the ceria-based electrolytes, this electrolyte can also be used at low oxygen partial pressures without the menace of developing an electronic conductivity. When in contact with cathodes of the LSM- or LSC type, some diffusion of manganese and cobalt from the cathode into the electrolyte is possible, but this has little effect on the fuel cell s performance. A certain defect of this electrolyte material is its complicated preparation procedure. 

A substantially more conductive material that is stable in air and hydrogen was discovered by Goodenough (9). Lanthanum gallate with strontium doping on the A-site of the perovskite and magnesium on the B-site could be used at temperatures as low as 600 °C even on a thick electrolyte. Laboratory fuel cells with this electrolyte have been tested, but the typical... 

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