Reactivity of CO and C2H4 on Bimetallic PtxAg1-x/Pt(111) Surface Alloys Investigated by High-Resolution X-ray Photoelectron Spectroscopy

Journal article


Publication Details

Author(s): Bauer U, Späth F, Düll F, Bachmann P, Steinhauer J, Steinrück HP, Papp C
Journal: Chemphyschem
Publisher: WILEY-V C H VERLAG GMBH
Publication year: 2018
Volume: 19
Journal issue: 12
Pages range: 1432-1440
ISSN: 1439-4235


Abstract

We have investigated the adsorption and thermal reactivity of CO and C2H4 on well-defined bimetallic PtxAg1-x/Pt(111) surface alloys (with x=0.67, 0.50, 0.38 and 0.32) using insitu synchrotron-based high-resolution X-ray photoelectron spectroscopy. During low-temperature (140K) adsorption of CO, we find population of the energetically more stable Pt on-top site followed by the Pt bridge site, as known from clean Pt(111); CO does not adsorb on Ag facets under the applied conditions. The total CO coverage linearly decreases with Ag surface content. Upon heating, COon-top and CObridge desorb at higher temperatures than on bare Pt(111), for example, by approximate to 65K for COon-top for an Ag content of 33%. This shift is due to the well-known electronic ligand-effect of Ag atoms surrounding Pt atoms/clusters. For C2H4 adsorption on the AgPt alloys at low temperature (120K), we find two species in the C1s XP spectrum, each displaying a vibrational fine structure; this contrasts the situation on clean Pt(111), where only one species is found. Upon heating, ethylene reacts with ethylidyne being the dominant intermediate; in contrast to clean Pt(111), on the alloy surfaces the reaction to CCH3 occurs at much lower temperatures, e.g. by approximate to 60K for the alloy with 68% Ag, and no ethylene desorption is found.


FAU Authors / FAU Editors

Bauer, Udo Dr.
Lehrstuhl für Physikalische Chemie II
Düll, Fabian
Lehrstuhl für Physikalische Chemie II
Papp, Christian PD Dr.
Lehrstuhl für Physikalische Chemie II
Späth, Florian
Lehrstuhl für Physikalische Chemie II
Steinhauer, Johann
Lehrstuhl für Physikalische Chemie II
Steinrück, Hans-Peter Prof. Dr.
Lehrstuhl für Physikalische Chemie II


Additional Organisation
Exzellenz-Cluster Engineering of Advanced Materials


How to cite

APA:
Bauer, U., Späth, F., Düll, F., Bachmann, P., Steinhauer, J., Steinrück, H.-P., & Papp, C. (2018). Reactivity of CO and C2H4 on Bimetallic PtxAg1-x/Pt(111) Surface Alloys Investigated by High-Resolution X-ray Photoelectron Spectroscopy. Chemphyschem, 19(12), 1432-1440. https://dx.doi.org/10.1002/cphc.201800044

MLA:
Bauer, Udo, et al. "Reactivity of CO and C2H4 on Bimetallic PtxAg1-x/Pt(111) Surface Alloys Investigated by High-Resolution X-ray Photoelectron Spectroscopy." Chemphyschem 19.12 (2018): 1432-1440.

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Last updated on 2018-02-08 at 13:08

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