Redox Behavior of Pt/Co3O4(111) Model Electrocatalyst Studied by X-ray Photoelectron Spectroscopy Coupled with an Electrochemical Cell
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10405807" target="_blank" >RIV/00216208:11320/19:10405807 - isvavai.cz</a>
Výsledek na webu
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=_iusne5Wdi" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=_iusne5Wdi</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/acs.jpcc.8b08890" target="_blank" >10.1021/acs.jpcc.8b08890</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Redox Behavior of Pt/Co3O4(111) Model Electrocatalyst Studied by X-ray Photoelectron Spectroscopy Coupled with an Electrochemical Cell
Popis výsledku v původním jazyce
Achieving high stability of supported noble metal nanoparticles with respect to sintering is one of the major challenges in electrocatalysis. In this study, we explored the role of metal-support interaction in stabilizing the morphology of a well-defined model electrode consisting of Pt nanoparticles supported on well-ordered Co3O4(111) films on Ir(100). We employed X-ray photoelectron spectroscopy coupled with an electrochemical cell to analyze changes in the oxidation states of both the supported Pt nanoparticles and Co3O4(111) support as a function of electrode potential. We found that immersion into the aqueous electrolyte at pH 10 (phosphate buffer) has no effect on the integrity and chemical composition of the Co3O4(111) film in a potential window between 0.5 and 1.4 V-RHE. At lower potentials, reduction of the Co3O4(111) to Co(OH)(2) and metallic Co is accompanied by rapid dissolution of the film. In the presence of supported Pt particles, metal-support interaction gives rise to the formation of partially oxidized Pt delta+ species at the metal/oxide interface. Under electrochemical conditions, these species are readily oxidized yielding platinum oxide at the Pt/Co3O4(111) interface at potentials as low as 0.5 V-RHE. The appearance of interfacial platinum oxide is accompanied by the formation of surface and bulk platinum oxides at potentials above 1.0 and 1.1 V-RHE, respectively. While the formation and decomposition of surface and bulk platinum oxides depend on the electrode potential, the interface platinum oxide is stable between 0.5 and 1.4 V-RHE. We propose that the high stability of supported Pt nanoparticles with respect to sintering is associated with the presence of platinum interface oxide stabilized by the metal-support interaction.
Název v anglickém jazyce
Redox Behavior of Pt/Co3O4(111) Model Electrocatalyst Studied by X-ray Photoelectron Spectroscopy Coupled with an Electrochemical Cell
Popis výsledku anglicky
Achieving high stability of supported noble metal nanoparticles with respect to sintering is one of the major challenges in electrocatalysis. In this study, we explored the role of metal-support interaction in stabilizing the morphology of a well-defined model electrode consisting of Pt nanoparticles supported on well-ordered Co3O4(111) films on Ir(100). We employed X-ray photoelectron spectroscopy coupled with an electrochemical cell to analyze changes in the oxidation states of both the supported Pt nanoparticles and Co3O4(111) support as a function of electrode potential. We found that immersion into the aqueous electrolyte at pH 10 (phosphate buffer) has no effect on the integrity and chemical composition of the Co3O4(111) film in a potential window between 0.5 and 1.4 V-RHE. At lower potentials, reduction of the Co3O4(111) to Co(OH)(2) and metallic Co is accompanied by rapid dissolution of the film. In the presence of supported Pt particles, metal-support interaction gives rise to the formation of partially oxidized Pt delta+ species at the metal/oxide interface. Under electrochemical conditions, these species are readily oxidized yielding platinum oxide at the Pt/Co3O4(111) interface at potentials as low as 0.5 V-RHE. The appearance of interfacial platinum oxide is accompanied by the formation of surface and bulk platinum oxides at potentials above 1.0 and 1.1 V-RHE, respectively. While the formation and decomposition of surface and bulk platinum oxides depend on the electrode potential, the interface platinum oxide is stable between 0.5 and 1.4 V-RHE. We propose that the high stability of supported Pt nanoparticles with respect to sintering is associated with the presence of platinum interface oxide stabilized by the metal-support interaction.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10305 - Fluids and plasma physics (including surface physics)
Návaznosti výsledku
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)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Ostatní
Rok uplatnění
2019
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
Journal of Physical Chemistry C
ISSN
1932-7447
e-ISSN
—
Svazek periodika
123
Číslo periodika v rámci svazku
14
Stát vydavatele periodika
US - Spojené státy americké
Počet stran výsledku
13
Strana od-do
8746-8758
Kód UT WoS článku
000464768600031
EID výsledku v databázi Scopus
2-s2.0-85063533230