Synthesis and characterization of La0.9Sr0.1Ga0.8Mg0.2O3-δ intermediate-temperature electrolyte using conventional solid state reaction

The perovskite-type La0.9Sr0.1Ga0.8Mg0.2O3-delta(LSGM9182) with high oxygen-ionic conductivity is successfully synthesized using conventional solid-state reaction. The phase composition, grain size distribution, relative density, and oxygen-ionic conductivity of the samples are studied. The XRD result shows that the main perovskite LaGaO3 phase can be produced at 1,250 degrees C, with trace amount of second phase LaSrGaO4. When the temperature increases to 1,400 degrees C, the pure phase LSGM can be obtained. The relative density of LSGM pellets sintered at 1,400 degrees C reaches 98.08%. The average grain size of final powders is similar to 0.12 mu m, which is appropriate for the deposition of LSGM electrolyte film. The ideal oxygen-ionic conductivities of 0.04, 0.06, and 0.08 S cm(-1) can be obtained at 700 degrees C, 750 degrees C, and 800 degrees C, respectively. Porous anode supported single cells with LSGM electrolyte film are fabricated using the as-prepared LSGM powders and the cells provide an open-circuit voltage of above 1.0 V. revealing that the LSGM film is gas-tight and crack-free. (C) 2012 Elsevier B.V. All rights reserved.