Strontium-doped, lanthanum chromite

Meadowcroft DB. Some properties of strontium-doped lanthanum chromite. Brit. J. Appl. Phys. 1969 D2 1225-1233. 

Tai TW and Lessing PA. Modified resin-intermediate of perovskite powders. Part II. Processing for fine, nonagglomerated strontium-doped lanthanum chromite powders. J. Mater. Res. 1992 7 511-519. 

Deshpande K, Mukasyan A, and Varma A. Aqueous combustion synthesis of strontium-doped lanthanum chromite ceramics. J. Am. Ceram. Soc. 2003 86 1149-1154. 

Paulik SW, Hardy J, Stevenson JW, and Armstrong TR. Sintering of non-stoichiomet-ric strontium doped lanthanum chromite, J. Mater. Lett. 2000 19 863-865. 

Muller, R. et al.. Investigations on selected gallium and strontium doped lanthanum chromites as electrode materials for HC detection. Ionics 8 (2(X)2) 262-266. 

Other materials have been studied as catalysts for steam methane reforming. Platinum, rhodium, and ruthenium have high catalytic activity for methane reforming. Suzuki et al. [23] studied the RuAfSZ cermet. They observed that ruthenium had a great activity and a high resistance to carbon deposition. Some promising results have been obtained with ruthenium inserted into strontium doped lanthanum chromite [24]. 

Indium oxide with different additives was proposed as a cathode material in 1956 [109] and frequently used (e.g. [110,107,108]). How ever, electronically conducting perovskites soon began to dominate the developments for both cathode and interconnect. The use of Lai- -Sr CoOs for the air electrode of solid oxide fuel cells marked the beginning [111], followed in 1967 by recommendations of PrCoOs [112] and of mixtures of the oxides of Pr. Cr, Ni and Co [113]. Strontium-doped lanthanum chromite, even now the most important ceramic interconnection material, was proposed by Meadowcroft in 1969 [114]. For cathodes, the situation in 1969 was summarised [115] as It Is apparent that a fully satisfactory air electrode for high temperature zirconia electrolyte fuel cells is still lacking. ... 

For strontium-doped lanthanum chromites, the precipitation of SrO is not possible, because strontium ions are more stable in the perovskite stmctuie than the lanthanum ions. Lanthanum oxide, La203, is often precipitated instead of SrO. This causes the disintegration of sintered specimens at ambient temperatures by the volume change associated with the formation of lanthanum hydroxide, La(OH)3, due to the reaction of La203 with the water vapor in the air (Meadowcroft, 1969 Sakai et al., 1990a). The substitution of transition metals such as zinc (Hayashi et al., 1988), cobalt (Zhou et al., 1996), or vanadium (Larsen et al., 1997) have been used to improve the sintering of strontium substituted lanthanum chromite. The substitution of strontium and transition metals is often utilized for intercoimects of the planar type... 

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