Propiedades Catalíticas de Nanocompuestos de NiO/CeO2-Sm2O3 para Celdas de Combustible de Óxido Sólido de Temperatura Intermedia

M. BELLORA; R. BACANI; L. TOSCANI; M. MAZAN; T. MARTINS; R. J. PRADO; M.F.C.A. FANTINI; S.A. LARRONDO.; D.G. LAMAS

Santa Fe

Congreso; CONGRESO INTERNACIONAL DE METALURGIA Y MATERIALES SAM-CONAMET/IBEROMAT/MATERIA 2014; 2014

Sociedad Argentina de Materiales

CeO2-based materials have received great attention due to their excellent catalytic properties for oxidation reactions. In the field of intermediate-temperaturesolid-oxide fuel cells (IT-SOFCs), CeO2-based anodes are subject of intense study because they have proven to exhibit excellent catalytic properties for bothpartial oxidation of hydrocarbons in single-chamber SOFCs and direct oxidation of hydrocarbons in conventional (two-chamber) SOFCs. Besides, excellentperformance in hydrogen-fueled SOFCs has also been found. These excellent performances of CeO2-based anodes is related to the fact that they are mixedionic/electronic conductors (MIECs) under reducing atmosphere and, therefore, fuel oxidation takes place on its entire surface, while it only occurs in the[anode/electrolyte/gas] triple-phase boundaries for electronic conductors. It is important to point out that the number of active points for fuel oxidation should bedramatically increased in nanostructured, high specific surface area MIECs.In this work, we present an in-situ study of Ni/CeO2-Sm2O3 nanocomposites for IT-SOFC anodes by DXAS technique. We studied the Ni-K and Ce-LIII edgesunder different operating conditions for H2 or CH4 oxidation. In this way, we monitor the Ni0/Ni2+ and Ce3+/Ce4+ ratios, which are strongly related to the catalyticproperties of these materials. In all cases, the reactions were monitored with a mass spectrometer.