In Situ Spectroscopy and Microscopy Insights into the CO Oxidation Mechanism on Au/CeO2(111)
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F22%3A10456752" target="_blank" >RIV/00216208:11320/22:10456752 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=_bfBu2VjD7" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=_bfBu2VjD7</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/acsami.2c15792" target="_blank" >10.1021/acsami.2c15792</a>
Alternative languages
Result language
angličtina
Original language name
In Situ Spectroscopy and Microscopy Insights into the CO Oxidation Mechanism on Au/CeO2(111)
Original language description
In this work, we prepared and investigated in ultrahigh vacuum (UHV) two stoichiometric CeO2(111) surfaces containing low and high amounts of step edges decorated with 0.05 ML of gold using synchrotron-radiation photoelectron spectroscopy (SRPES) and scanning tunneling microscopy (STM). The UHV study helped to solve the still unresolved puzzle on how the one-monolayer-high ceria step edges affect the metal- substrate interaction between Au and the CeO2(111) surface. It was found that the concentration of ionic Au+ species on the ceria surface increases with increasing number of ceria step edges and is not correlated with the concentration of Ce3+ ions that are supposed to form on the surface after its interaction with gold nanoparticles. We associated this with an additional channel of Au+ formation on the surface of CeO2(111) related to the interaction of Au atoms with various peroxo oxygen species formed at the ceria step edges during the film growth. The study of CO oxidation on the highly stepped Au/CeO2(111) model sample was performed by combining near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS), UHV-STM, and near-ambient-pressure STM (NAP-STM). This powerful combination provided comprehensive information on the processes occurring on the Au/CeO2(111) surface during the interaction with CO, O2, and CO + O2 (1:1) mixture at conditions close to the real working conditions of CO oxidation. It was found that the system demonstrates high stability in CO. However, the surface undergoes substantial chemical and morphological changes as the O2 is added to the reaction cell. Already at 300 K, gold nanoparticles begin to grow using a mechanism that involves the disintegration of small gold nanoparticles in favor of the large ones. With increasing temperature, the model catalyst quickly transforms into a system of primarily large Au particles that contains no ionic gold species.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10305 - Fluids and plasma physics (including surface physics)
Result continuities
Project
Result was created during the realization of more than one project. More information in the Projects tab.
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
ACS Applied Materials & Interfaces
ISSN
1944-8244
e-ISSN
1944-8252
Volume of the periodical
14
Issue of the periodical within the volume
50
Country of publishing house
US - UNITED STATES
Number of pages
10
Pages from-to
56280-56289
UT code for WoS article
000895462200001
EID of the result in the Scopus database
2-s2.0-85143856375