Influence of the metal precursor on the catalytic behavior of Pt/ceria catalysts in the preferential oxidation of CO in the presence of H₂ (PROX)

Erika O Jardim; Soledad Rico-Francés; Fernando Coloma; James A Anderson; Joaquín Silvestre-Albero; Antonio Sepúlveda-Escribano

doi:10.1016/j.jcis.2014.12.013

Influence of the metal precursor on the catalytic behavior of Pt/ceria catalysts in the preferential oxidation of CO in the presence of H₂ (PROX)

J Colloid Interface Sci. 2015 Apr 1:443:45-55. doi: 10.1016/j.jcis.2014.12.013. Epub 2014 Dec 10.

Authors

Erika O Jardim¹, Soledad Rico-Francés¹, Fernando Coloma¹, James A Anderson², Joaquín Silvestre-Albero¹, Antonio Sepúlveda-Escribano³

Affiliations

¹ Laboratorio de Materiales Avanzados, Departamento de Química Inorgánica - Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Apartado 99, E-03080 Alicante, Spain.
² Surface Chemistry and Catalysis Group, Department of Chemistry and School of Engineering, University of Aberdeen, AB24 3UE Scotland, UK.
³ Laboratorio de Materiales Avanzados, Departamento de Química Inorgánica - Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Apartado 99, E-03080 Alicante, Spain. Electronic address: asepul@ua.es.

PMID: 25531415
DOI: 10.1016/j.jcis.2014.12.013

Abstract

The effect of the metal precursor (presence or absence of chlorine) on the preferential oxidation of CO in the presence of H2 over Pt/CeO2 catalysts has been studied. The catalysts are prepared using (Pt(NH3)4)(NO3)2 and H2PtCl6, as precursors, in order to ascertain the effect of the chlorine species on the chemical properties of the support and on the catalytic behavior of these systems in the PROX reaction. The results show that chloride species exert an important effect on the redox properties of the oxide support due to surface chlorination. Consequently, the chlorinated catalyst exhibits a poorer catalytic activity at low temperatures compared with the chlorine-free catalyst, and this is accompanied by a higher selectivity to CO2 even at high reaction temperatures. It is proposed that the CO oxidation mechanism follows different pathways on each catalyst.

Keywords: Ceria; DRIFTS; Metal precursor; PROX; Pt.