Meta-stability and microstructure of the LaFe0.65Co0.3Pd0.05O3 perovskite compound prepared by a modified citrate route

• Published in: Journal of the European Ceramic Society 2008-09, Vol.28 (13), p.2611-2616
• Main Authors: MONDRAGON RODRIGUEZ, G. C, OCHROMBEL, R, SARUHAN, B
• Format: Article
• Language: English
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Catalysis; Catalysts: preparations and properties; Ceramic industries; Chemical industry and chemicals; Chemistry; Exact sciences and technology; General and physical chemistry; Miscellaneous; Technical ceramics; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2008.03.020

The synthesis and analysis of lanthanum based perovskites substituted with Pd, suitable for automotive catalysts, using a modified citrate route are reported. Crystallisation and phase sequences of the LaFe0.65Co0.3-xPdxO3 (x = ,0.05) perovskite(s) were analysed by powder XRD and Rietveld refinement. Regarding the crystal phase development of the LaFe0.65Co0.3Pd0.05O3 perovskite, a meta-stable structure could be postulated at temperatures up to 700 C. Since no PdO species were detected up to the calcination temperature of 700 C it could be concluded that Pd ions were successfully incorporated into the B-site of the crystal structure of the perovskite. Reduction of the LaFe0.65Co0.3Pd0.05O3 perovskite at 600 C under 5 vol% H2 in N2 which was precalcined at 700 C caused segregation of Pd to form metallic particles with sizes between 10 and 15 nm. Reincorporation of reversible Pd ions into the crystal lattice of the LaFe0.65Co0.3Pd0.05O3-700 C perovskite could be concluded since no PdO was detected after re-oxidation at 600 C. 15 refs.