Redox Behavior of Pt/Co3O4(111) Model Electrocatalyst Studied by X-ray Photoelectron Spectroscopy Coupled with an Electrochemical Cell

Beitrag in einer Fachzeitschrift


Details zur Publikation

Autorinnen und Autoren: Brummel O, Lykhach Y, Vorokhta M, Smid B, Stumm C, Faisal F, Skala T, Tsud N, Neitzel A, Beranova K, Prince KC, Matolin V, Libuda J
Zeitschrift: Journal of Physical Chemistry C
Jahr der Veröffentlichung: 2019
Band: 123
Heftnummer: 14
Seitenbereich: 8746-8758
ISSN: 1932-7447
eISSN: 1932-7455


Abstract

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 Co
3
O
4
(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 Co
3
O
4
(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 Co
3
O
4
(111) film in a potential window between 0.5 and 1.4 V
RHE
. At lower potentials, reduction of the Co
3
O
4
(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
δ+
species at the metal/oxide interface. Under electrochemical conditions, these species are readily oxidized yielding platinum oxide at the Pt/Co
3
O
4
(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. ©


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Brummel, Olaf Dr.
Lehrstuhl für Physikalische Chemie II
Faisal, Firas
Lehrstuhl für Physikalische Chemie II
Libuda, Jörg Prof. Dr.
Lehrstuhl für Katalytische Grenzflächenforschung
Lykhach, Yaroslava
Lehrstuhl für Physikalische Chemie II
Neitzel, Armin
Lehrstuhl für Physikalische Chemie II
Stumm, Corinna
Lehrstuhl für Physikalische Chemie II


Einrichtungen weiterer Autorinnen und Autoren

Elettra Sincrotrone Trieste S.C.p.A.
Univerzita Karlova v Praze / Charles University in Prague


Zitierweisen

APA:
Brummel, O., Lykhach, Y., Vorokhta, M., Smid, B., Stumm, C., Faisal, F.,... Libuda, J. (2019). Redox Behavior of Pt/Co3O4(111) Model Electrocatalyst Studied by X-ray Photoelectron Spectroscopy Coupled with an Electrochemical Cell. Journal of Physical Chemistry C, 123(14), 8746-8758. https://dx.doi.org/10.1021/acs.jpcc.8b08890

MLA:
Brummel, Olaf, et al. "Redox Behavior of Pt/Co3O4(111) Model Electrocatalyst Studied by X-ray Photoelectron Spectroscopy Coupled with an Electrochemical Cell." Journal of Physical Chemistry C 123.14 (2019): 8746-8758.

BibTeX: 

Zuletzt aktualisiert 2019-06-08 um 09:06

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