Zirconia supported La, Co oxides and LaCoO3 perovskite: structural characterization and catalytic CO oxidation

✍ Scribed by S. Colonna; S. De Rossi; M. Faticanti; I. Pettiti; P. Porta

• Book ID: 104421734
• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 146 KB
• Volume: 180
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(01)00422-8

✦ Synopsis

ZrO 2 -supported La, Co oxide catalysts with different La, Co loading (2, 6, 8, 12 and 16 wt.% as LaCoO 3 ) were prepared by impregnation of tetragonal ZrO 2 with equimolar amounts of La and Co citrate precursors and calcination at 1073 K. The catalysts were characterized by X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), and BET specific surface area determination. Catalytic CO oxidation was performed at 298-800 K. XRD revealed the presence of tetragonal zirconia with traces of the monoclinic phase. LaCoO 3 perovskite was also detected for loading higher than 6%. XAS experiments suggested that at high loading LaCoO 3 and Co 3 O 4 were formed, while at low loading, La, Co oxide species interacting with support, and hard to be structurally defined, prevailed. The catalysis study evidenced that the catalytic activity was due to segregated and highly dispersed cobalt oxide species.