화학공학소재연구정보센터
Solid State Ionics, Vol.178, No.25-26, 1476-1486, 2007
Conductivity of strontium- and lithium-doped-lanthanum orthogallate (La0.9Sr0.1Ga1-yLiyO3-delta; y=0.05 and 0.10) synthesized via metal nitrate-glycine gel route
Strontium- and magnesium-doped-lanthanum orthogallate have emerged as promising alternative solid electrolytes for solid-oxide fuel cells in the intermediate-temperature regime. In accordance with the theoretical consideration, doping by a monovalent ion at the B-site is envisaged to increase the defect concentration and enhance the oxide ion conductivity. With this aim, strontium- and lithium-doped-lanthanum orthogallate formulations (La0.9Sr0.1Ga1-yLiyO3-delta; y=0.05 and 0.10) were synthesized via soft-chemistry route of metal nitrate-glycine combustion. Systematic phase and microstructural evolution as a function of processing temperature was followed by X-ray diffraction and scanning electron microscopy of the calcined and sintered samples. Electrical characterization on the sintered sample by the 4-point DC and AC impedance measurements in the temperature range of 550-850 degrees C showed that Li-doping at B-site in LaGaO3 yielded conductivity higher than that of yttria-stabilized zirconia, but somewhat inferior to the Mg-doped analogs. (c) 2007 Published by Elsevier B.V.