Interaction of sulfur with Au/Pt(111) and Ag/Pt(111) surfaces: Photoemission studies

Journal Article · Thu Sep 19 04:00:00 EDT 1996 · Journal of Physical Chemistry

DOI:https://doi.org/10.1021/jp9607632· OSTI ID:420815

Rodriguez, J A; Kuhn, M; Hrbek, J ^[1]

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1. Brookhaven National Lab., Upton, NY (United States)

The reaction of sulfur with Au/Pt(111) and Ag/Pt(111) surfaces has been investigated using high-resolution photoemission spectroscopy with synchrotron radiation. The valence spectra of S/Au/Pt(111) and S/Ag/Pt-(111) surfaces display weak signals at binding energies between 1.8 and 0 eV. The adsorption of S induces a large decrease in the density of states displayed by the bimetallic surfaces around the Fermi level. This phenomenon may be responsible for the decrease in chemical and catalytic activity that accompanies sulfur poisoning. In S/Au/Pt(111) surfaces, sulfur does not form compounds with Au or Pt. Au forms three-dimensional clusters, while S segregates into two-dimensional islands of high local coverage where it is bonded to hollow and bridge sites of the Pt substrate. In S/Ag/Pt(111) surfaces, silver reacts with sulfur and promotes the synthesis of platinum sulfides. The formation of silver and platinum sulfides makes possible the adsorption of large amounts of sulfur on Ag/Pt(111) surfaces. The S/Au/Pt(111) and S/Ag/Pt(111) systems illustrate different extremes of the phenomena that can occur when sulfur is present on a bimetallic surface. The differences in the behavior of the S/Au/Pt(111) and S/Ag/Pt(111) surfaces arise from variations in the nature of the admetal S and admetal Pt interactions. 45 refs., 13 figs.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 420815
• Journal Information: Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 38 Vol. 100; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
ADSORPTION
BINDING ENERGY
CHEMICAL REACTIONS
EMISSION SPECTRA
FERMI LEVEL
GOLD
PLATINUM
PLATINUM SULFIDES
SILVER
SILVER SULFIDES
SULFUR
SURFACES
SYNCHROTRON RADIATION