Raman in situ characterization of the species present in Co/CeO2 and Co/ZrO2 catalysts during the COPrOx reaction

The in situ Raman spectroscopy constitutes a powerful procedure to characterize catalytic surfaces under reaction conditions. In this work, we studied the species present in Co/CeO2 and Co/ZrO2 catalysts during the COPrOx reaction carried out between room temperature and 500 °C. For both catalysts,...

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Detalles Bibliográficos
Autores: Gómez, Leticia Ester, Múnera Agudelo, John Fernando, Sollier, Brenda Maria del Valle, Miro, Eduardo Ernesto, Boix, Alicia Viviana
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/36655
Acceso en línea:http://hdl.handle.net/11336/36655
Access Level:acceso abierto
Palabra clave:Cobalt
Coprox
In Situ Raman
https://purl.org/becyt/ford/2.5
https://purl.org/becyt/ford/2
Descripción
Sumario:The in situ Raman spectroscopy constitutes a powerful procedure to characterize catalytic surfaces under reaction conditions. In this work, we studied the species present in Co/CeO2 and Co/ZrO2 catalysts during the COPrOx reaction carried out between room temperature and 500 °C. For both catalysts, TPR and Raman results suggest that a redox mechanism proceeds in which the reduction step with either hydrogen or CO is the rate-limiting step. The CeO2 support is better than the ZrO2 one because the former accelerates the surface exchange between reduced and oxidized species due to the high mobility of surface lattice oxygen and the presence of oxygen vacancies. The Ce4+ + Co2+ ↔ Ce3+ + Co3+ process acts as a buffer effect by which Co3+, which is the active species in this reaction, is always present even in a reducing atmosphere, as shown by in situ Raman characterization.