Probing the redox capacity of Pt-CeO2 model catalyst for low-temperature CO oxidation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F23%3A10468335" target="_blank" >RIV/00216208:11320/23:10468335 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=WurNqES-Pg" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=WurNqES-Pg</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d3ta02507a" target="_blank" >10.1039/d3ta02507a</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Probing the redox capacity of Pt-CeO2 model catalyst for low-temperature CO oxidation

Popis výsledku v původním jazyce

The redox capacity of Pt-CeO2 catalysts for low-temperature CO oxidation has been investigated by means of near-ambient pressure X-ray photoelectron spectroscopy, synchrotron radiation photoelectron spectroscopy, and resonant photoemission spectroscopy. The well-defined model Pt-CeO2 systems containing specific Pt species which differ with respect to the oxidation state, chemical environment, and nuclearity, including atomically dispersed Pt2+ and Pt4+ species, metallic Pt-0 nanoparticles, ultra-small Pt* aggregates, and PtOx clusters were prepared by physical vapor co-deposition of Pt and Ce metals in an oxygen atmosphere onto a CeO2(111) buffer layer on Ru(0001) and subsequent annealing under reducing or oxidizing conditions. The oxidation states of Pt species and Ce cations were monitored upon CO exposure as a function of temperature. We found that metallic Pt-0 nanoparticles, ultra-small Pt*/PtOx clusters, and Pt4+ species serve as CO adsorption sites at low temperature. Exclusively, the redox capacity for the low-temperature CO oxidation (below the room temperature) was observed only for the Pt-CeO2 catalyst containing metallic Pt-0 nanoparticles. The corresponding redox pathway is associated with CO spillover and the formation of bidentate carbonate species. Above 400 K, the redox interaction of CO with model Pt-CeO2 catalysts involves the Mars-van Krevelen mechanism regardless of the nature of the Pt species.

Název v anglickém jazyce

Probing the redox capacity of Pt-CeO2 model catalyst for low-temperature CO oxidation

Popis výsledku anglicky

The redox capacity of Pt-CeO2 catalysts for low-temperature CO oxidation has been investigated by means of near-ambient pressure X-ray photoelectron spectroscopy, synchrotron radiation photoelectron spectroscopy, and resonant photoemission spectroscopy. The well-defined model Pt-CeO2 systems containing specific Pt species which differ with respect to the oxidation state, chemical environment, and nuclearity, including atomically dispersed Pt2+ and Pt4+ species, metallic Pt-0 nanoparticles, ultra-small Pt* aggregates, and PtOx clusters were prepared by physical vapor co-deposition of Pt and Ce metals in an oxygen atmosphere onto a CeO2(111) buffer layer on Ru(0001) and subsequent annealing under reducing or oxidizing conditions. The oxidation states of Pt species and Ce cations were monitored upon CO exposure as a function of temperature. We found that metallic Pt-0 nanoparticles, ultra-small Pt*/PtOx clusters, and Pt4+ species serve as CO adsorption sites at low temperature. Exclusively, the redox capacity for the low-temperature CO oxidation (below the room temperature) was observed only for the Pt-CeO2 catalyst containing metallic Pt-0 nanoparticles. The corresponding redox pathway is associated with CO spillover and the formation of bidentate carbonate species. Above 400 K, the redox interaction of CO with model Pt-CeO2 catalysts involves the Mars-van Krevelen mechanism regardless of the nature of the Pt species.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Materials Chemistry A

ISSN

2050-7488

e-ISSN

2050-7496

Svazek periodika

11

Číslo periodika v rámci svazku

31

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

16659-16670

Kód UT WoS článku

001025117500001

EID výsledku v databázi Scopus

2-s2.0-85165510030