Atomic Ordering and Sn Segregation in Pt-Sn Nanoalloys Supported on CeO2 Thin Films

Beitrag in einer Fachzeitschrift


Details zur Publikation

Autorinnen und Autoren: Neitzel A, Kovacs G, Lykhach Y, Kozlov SM, Tsud N, Skala T, Vorokhta M, Matolin V, Neyman KM, Libuda J
Zeitschrift: Topics in Catalysis
Verlag: SPRINGER/PLENUM PUBLISHERS
Jahr der Veröffentlichung: 2017
Band: 60
Heftnummer: 6-7
Seitenbereich: 522-532
ISSN: 1022-5528


Abstract

The stability and atomic ordering in Pt-Sn nanoalloys supported on CeO2 thin films have been studied by means of synchrotron radiation photoelectron spectroscopy and density functional calculations. Using CO molecules as a probe, we explored the development of the surface structure of supported Pt-Sn nanoalloys with respect to a reference Pt/CeO2 model system. We found a significant decrease in the density of CO adsorption sites on supported Pt-Sn nanoalloys caused by Sn segregation to the surface upon annealing. Additionally, we found that atomic ordering in Pt-Sn nanoalloys is driven by the balance between the surface segregation energy of Sn atoms and the energy of heteroatomic bond formation. Our calculations demonstrate a clear tendency for Sn segregation to the nanoalloy surface. For Pt105Sn35 and Pt1097Sn386 nanoparticles, we calculated a surface stoichiometry of Pt2Sn which is only slightly dependent on temperature in thermodynamic equilibrium. The analysis of Bader charges in Pt-Sn nanoalloys revealed a strong correlation between the charge and the coordination number of Sn atoms with respect to Pt neighbors. In particular, the magnitude of the charge transfer from Sn to Pt increases as a function of the Sn coordination number.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Libuda, Jörg Prof. Dr.
Professur für Physikalische Chemie
Lykhach, Yaroslava
Lehrstuhl für Physikalische Chemie II
Neitzel, Armin
Lehrstuhl für Physikalische Chemie II


Zusätzliche Organisationseinheit(en)
Exzellenz-Cluster Engineering of Advanced Materials


Einrichtungen weiterer Autorinnen und Autoren

Universitat de Barcelona (UB) / University of Barcelona
Univerzita Karlova v Praze / Charles University in Prague


Forschungsbereiche

D Catalytic Materials
Exzellenz-Cluster Engineering of Advanced Materials


Zitierweisen

APA:
Neitzel, A., Kovacs, G., Lykhach, Y., Kozlov, S.M., Tsud, N., Skala, T.,... Libuda, J. (2017). Atomic Ordering and Sn Segregation in Pt-Sn Nanoalloys Supported on CeO2 Thin Films. Topics in Catalysis, 60(6-7), 522-532. https://dx.doi.org/10.1007/s11244-016-0709-5

MLA:
Neitzel, Armin, et al. "Atomic Ordering and Sn Segregation in Pt-Sn Nanoalloys Supported on CeO2 Thin Films." Topics in Catalysis 60.6-7 (2017): 522-532.

BibTeX: 

Zuletzt aktualisiert 2019-20-02 um 08:38