Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation

Supported Pd/CeO2 catalytic systems have been widely investigated in the low-temperature oxidation of CO (LTO CO) due to the unique oxygen storage capacity and redox properties of the ceria support, which highly influence the structural, chemical and electronic state of Pd species. Herein, operando...

Descripción completa

Detalles Bibliográficos
Autores: García de Andrés, Xènia|||0000-0003-0795-4168, Soler Turu, Lluís|||0000-0003-1591-3366, Vendrell Villafruela, Xavier|||0000-0003-4705-8253, Serrano Carreño, M. Isabel|||0000-0002-4996-9280, Herrera, Facundo, Prat, Jordi, Solano Minuesa, Eduardo, Tallarida, Massimo, Llorca Piqué, Jordi|||0000-0002-7447-9582, Escudero, Carlos
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/386044
Acceso en línea:https://hdl.handle.net/2117/386044
https://dx.doi.org/10.3390/chemistry5010001
Access Level:acceso abierto
Palabra clave:Catalysis
Palladium catalyst
Cerium oxide
CO oxidation
NAP-XPS
Metal–support interaction
Catàlisi
Àrees temàtiques de la UPC::Enginyeria química
id ES_03df2ae8cd6e31edfea4e41816b20df0
oai_identifier_str oai:upcommons.upc.edu:2117/386044
network_acronym_str ES
network_name_str España
repository_id_str
spelling Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidationGarcía de Andrés, Xènia|||0000-0003-0795-4168Soler Turu, Lluís|||0000-0003-1591-3366Vendrell Villafruela, Xavier|||0000-0003-4705-8253Serrano Carreño, M. Isabel|||0000-0002-4996-9280Herrera, FacundoPrat, JordiSolano Minuesa, EduardoTallarida, MassimoLlorca Piqué, Jordi|||0000-0002-7447-9582Escudero, CarlosCatalysisPalladium catalystCerium oxideCO oxidationNAP-XPSMetal–support interactionCatàlisiÀrees temàtiques de la UPC::Enginyeria químicaSupported Pd/CeO2 catalytic systems have been widely investigated in the low-temperature oxidation of CO (LTO CO) due to the unique oxygen storage capacity and redox properties of the ceria support, which highly influence the structural, chemical and electronic state of Pd species. Herein, operando near-ambient pressure XPS (NAP-XPS) technique has allowed the study of a conventional Pd/CeO2 catalyst surface during the CO oxidation reaction under experimental conditions closer to the actual catalytic reaction, unfeasible with other surface science techniques that demand UHV conditions. SEM, HRTEM and XRD analyses of the powder catalyst, prepared by conventional incipient wetness impregnation, reveal uniformly CeO2-loaded Pd NPs of less than 2 nm size, which generated an increase in oxygen vacancies with concomitant ceria reduction, as indicated by H2-TPR and Raman measurements. Adsorbed peroxide (O22-) species on the catalyst surface could also be detected by Raman spectra. Operando NAP-XPS results obtained at the ALBA Synchrotron Light Source revealed two kinds of Pd species under reaction conditions, namely PdOx and PdII ions in a PdxCe1-xO2-d solution, the latter one appearing to be crucial for the CO oxidation. By means of a non-destructive depth profile analysis using variable synchrotron excitation energies, the location and the role of these palladium species in the CO oxidation reaction could be clarified: PdOx was found to prevail on the upper surface layers of the metallic Pd supported NPs under CO, while under reaction mixture it was rapidly depleted from the surface, leaving a greater amount in the subsurface layers (7% vs. 12%, respectively). On the contrary, the PdxCe1-xO2-d phase, which was created at the Pd–CeO2 interface in contact with the gas environment, appeared to be predominant on the surface of the catalyst. Its presence was crucial for CO oxidation evolution, acting as a route through which active oxygen species could be transferred from ceria to Pd species for CO oxidation.Peer ReviewedMultidisciplinary Digital Publishing Institute (MDPI)20222022-12-2020232023-04-06journal articlehttp://purl.org/coar/resource_type/c_6501VoRhttp://purl.org/coar/version/c_970fb48d4fbd8a85info:eu-repo/semantics/articleapplication/pdfhttps://hdl.handle.net/2117/386044https://dx.doi.org/10.3390/chemistry5010001reponame:UPCommons. Portal del coneixement obert de la UPCinstname:Universitat Politècnica de Catalunya (UPC)Inglésengopen accesshttp://purl.org/coar/access_right/c_abf2Attribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessoai:upcommons.upc.edu:2117/3860442026-05-27T15:37:01Z
dc.title.none.fl_str_mv Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
title Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
spellingShingle Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
García de Andrés, Xènia|||0000-0003-0795-4168
Catalysis
Palladium catalyst
Cerium oxide
CO oxidation
NAP-XPS
Metal–support interaction
Catàlisi
Àrees temàtiques de la UPC::Enginyeria química
title_short Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
title_full Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
title_fullStr Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
title_full_unstemmed Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
title_sort Operando NAP-XPS studies of a ceria-supported Pd catalyst for CO oxidation
dc.creator.none.fl_str_mv García de Andrés, Xènia|||0000-0003-0795-4168
Soler Turu, Lluís|||0000-0003-1591-3366
Vendrell Villafruela, Xavier|||0000-0003-4705-8253
Serrano Carreño, M. Isabel|||0000-0002-4996-9280
Herrera, Facundo
Prat, Jordi
Solano Minuesa, Eduardo
Tallarida, Massimo
Llorca Piqué, Jordi|||0000-0002-7447-9582
Escudero, Carlos
author García de Andrés, Xènia|||0000-0003-0795-4168
author_facet García de Andrés, Xènia|||0000-0003-0795-4168
Soler Turu, Lluís|||0000-0003-1591-3366
Vendrell Villafruela, Xavier|||0000-0003-4705-8253
Serrano Carreño, M. Isabel|||0000-0002-4996-9280
Herrera, Facundo
Prat, Jordi
Solano Minuesa, Eduardo
Tallarida, Massimo
Llorca Piqué, Jordi|||0000-0002-7447-9582
Escudero, Carlos
author_role author
author2 Soler Turu, Lluís|||0000-0003-1591-3366
Vendrell Villafruela, Xavier|||0000-0003-4705-8253
Serrano Carreño, M. Isabel|||0000-0002-4996-9280
Herrera, Facundo
Prat, Jordi
Solano Minuesa, Eduardo
Tallarida, Massimo
Llorca Piqué, Jordi|||0000-0002-7447-9582
Escudero, Carlos
author2_role author
author
author
author
author
author
author
author
author
dc.subject.none.fl_str_mv Catalysis
Palladium catalyst
Cerium oxide
CO oxidation
NAP-XPS
Metal–support interaction
Catàlisi
Àrees temàtiques de la UPC::Enginyeria química
topic Catalysis
Palladium catalyst
Cerium oxide
CO oxidation
NAP-XPS
Metal–support interaction
Catàlisi
Àrees temàtiques de la UPC::Enginyeria química
description Supported Pd/CeO2 catalytic systems have been widely investigated in the low-temperature oxidation of CO (LTO CO) due to the unique oxygen storage capacity and redox properties of the ceria support, which highly influence the structural, chemical and electronic state of Pd species. Herein, operando near-ambient pressure XPS (NAP-XPS) technique has allowed the study of a conventional Pd/CeO2 catalyst surface during the CO oxidation reaction under experimental conditions closer to the actual catalytic reaction, unfeasible with other surface science techniques that demand UHV conditions. SEM, HRTEM and XRD analyses of the powder catalyst, prepared by conventional incipient wetness impregnation, reveal uniformly CeO2-loaded Pd NPs of less than 2 nm size, which generated an increase in oxygen vacancies with concomitant ceria reduction, as indicated by H2-TPR and Raman measurements. Adsorbed peroxide (O22-) species on the catalyst surface could also be detected by Raman spectra. Operando NAP-XPS results obtained at the ALBA Synchrotron Light Source revealed two kinds of Pd species under reaction conditions, namely PdOx and PdII ions in a PdxCe1-xO2-d solution, the latter one appearing to be crucial for the CO oxidation. By means of a non-destructive depth profile analysis using variable synchrotron excitation energies, the location and the role of these palladium species in the CO oxidation reaction could be clarified: PdOx was found to prevail on the upper surface layers of the metallic Pd supported NPs under CO, while under reaction mixture it was rapidly depleted from the surface, leaving a greater amount in the subsurface layers (7% vs. 12%, respectively). On the contrary, the PdxCe1-xO2-d phase, which was created at the Pd–CeO2 interface in contact with the gas environment, appeared to be predominant on the surface of the catalyst. Its presence was crucial for CO oxidation evolution, acting as a route through which active oxygen species could be transferred from ceria to Pd species for CO oxidation.
publishDate 2022
dc.date.none.fl_str_mv 2022
2022-12-20
2023
2023-04-06
dc.type.none.fl_str_mv journal article
http://purl.org/coar/resource_type/c_6501
VoR
http://purl.org/coar/version/c_970fb48d4fbd8a85
dc.type.openaire.fl_str_mv info:eu-repo/semantics/article
format article
dc.identifier.none.fl_str_mv https://hdl.handle.net/2117/386044
https://dx.doi.org/10.3390/chemistry5010001
url https://hdl.handle.net/2117/386044
https://dx.doi.org/10.3390/chemistry5010001
dc.language.none.fl_str_mv Inglés
eng
language_invalid_str_mv Inglés
language eng
dc.rights.none.fl_str_mv open access
http://purl.org/coar/access_right/c_abf2
Attribution-NonCommercial-NoDerivatives 4.0 International
http://creativecommons.org/licenses/by-nc-nd/4.0/
dc.rights.openaire.fl_str_mv info:eu-repo/semantics/openAccess
rights_invalid_str_mv open access
http://purl.org/coar/access_right/c_abf2
Attribution-NonCommercial-NoDerivatives 4.0 International
http://creativecommons.org/licenses/by-nc-nd/4.0/
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Multidisciplinary Digital Publishing Institute (MDPI)
publisher.none.fl_str_mv Multidisciplinary Digital Publishing Institute (MDPI)
dc.source.none.fl_str_mv reponame:UPCommons. Portal del coneixement obert de la UPC
instname:Universitat Politècnica de Catalunya (UPC)
instname_str Universitat Politècnica de Catalunya (UPC)
reponame_str UPCommons. Portal del coneixement obert de la UPC
collection UPCommons. Portal del coneixement obert de la UPC
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869402755805741056
score 15,300724