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Abstract: The effects of a V2O5 additive on the low-temperature sintering and ionic conductivity of strontium- and magnesium-doped lanthanum gallate (LSGM: La0.8Sr0.2Ga0.8Mg0.2O2.8) are studied. The LSGM powders prepared by the glycine nitrate method are mixed with 0.5–2at.% of VO5/2 and then sintered at 1100–1400°C in air for 4h. The apparent density and phase purity of the LSGM specimens are increased with increasing sintering temperature and VO5/2 concentration due to the enhanced sintering and mass transfer via the intergranular liquid phase. The 1at.% VO5/2-doped LSGM specimen sintered at 1300°C exhibits a high oxide ion conductivity of ∼0.027Scm−1 at 700°C over a wide range of oxygen partial pressure (), thereby demonstrating its potential as a useful electrolyte for anode-supported solid oxide fuel cells (SOFCs) without the requirement for any buffer layer between the electrolyte and anode. [ABSTRACT FROM AUTHOR]

Abstract: A range of La0.75Sr0.25Cr0.5Mn0.5O3−δ (LSCM) powders is prepared by the carbonate coprecipitation method for use as anodes in solid oxide fuel cells. The supersaturation ratio (R =[(NH4)2CO3]/([La3+]+[Sr2+]+[Cr3+]+[Mn2+])) during the coprecipitation determines the relative compositions of La, Sr, Cr, and Mn. The composition of the precursor approaches the stoichiometric one at the supersaturation range of 4≤ R ≤12.5, whereas Sr and Mn components are deficient at R <4 and excessive at R =25. The fine and phase-pure LSCM powders are prepared by heat treatment at very low temperature (1000°C) at R =7.5 and 12.5. By contrast, the solid-state reaction requires a higher heat-treatment temperature (1400°C). The catalytic activity of the LSCM electrodes is enhanced by using carbonate-derived powders to manipulate the electrode microstructures. [Copyright &y& Elsevier]