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Title: STM and XPS Study of Growth of Ce on Au(111)

Abstract

The growth of Ce on Au(111) was studied with STM and XPS in UHV. Ce islands grew on Au(111) without showing a preference for nucleation at elbows, as reported for some other clusters. XPS data show a shift of up to +0.4 eV for the Au 4f core level with increasing coverage of Ce to 2 ML at room temperature. The Ce 3d core level broadened upon heating, suggesting a strong interaction of Ce atoms with Au atoms. After heating to 470 K, the Au herringbone was distorted into trigonal structures while small Ce clusters with a narrow size distribution decorated the elbows and corners of the trigonal structures. Large islands displaying a moire pattern grew by alloying Ce atoms with Au surface in a broad size range. The second alloy phase, embedded into the surface as hexagonal islands with corners located on the herringbone stripes, has a strong resistance to oxidation by O{sub 2} and NO{sub 2}. Star-like coplanar structures seen at the intersection of six dislocation stripes are the preferential nucleation sites for the hexagonal islands.

Authors:
; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930421
Report Number(s):
BNL-81154-2008-JA
Journal ID: ISSN 1932-7447; TRN: US0901384
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry C; Journal Volume: 111
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ALLOYS; ATOMS; CERIUM; CRYSTAL GROWTH; DISLOCATIONS; GOLD; HEATING; NUCLEATION; OXIDATION; STRONG INTERACTIONS; X-RAY PHOTOELECTRON SPECTROSCOPY; national synchrotron light source

Citation Formats

Ma,S., Zhao, X., Rodriguez, J., and Hrbek, J. STM and XPS Study of Growth of Ce on Au(111). United States: N. p., 2007. Web. doi:10.1021/jp064366v.
Ma,S., Zhao, X., Rodriguez, J., & Hrbek, J. STM and XPS Study of Growth of Ce on Au(111). United States. doi:10.1021/jp064366v.
Ma,S., Zhao, X., Rodriguez, J., and Hrbek, J. Mon . "STM and XPS Study of Growth of Ce on Au(111)". United States. doi:10.1021/jp064366v.
@article{osti_930421,
title = {STM and XPS Study of Growth of Ce on Au(111)},
author = {Ma,S. and Zhao, X. and Rodriguez, J. and Hrbek, J.},
abstractNote = {The growth of Ce on Au(111) was studied with STM and XPS in UHV. Ce islands grew on Au(111) without showing a preference for nucleation at elbows, as reported for some other clusters. XPS data show a shift of up to +0.4 eV for the Au 4f core level with increasing coverage of Ce to 2 ML at room temperature. The Ce 3d core level broadened upon heating, suggesting a strong interaction of Ce atoms with Au atoms. After heating to 470 K, the Au herringbone was distorted into trigonal structures while small Ce clusters with a narrow size distribution decorated the elbows and corners of the trigonal structures. Large islands displaying a moire pattern grew by alloying Ce atoms with Au surface in a broad size range. The second alloy phase, embedded into the surface as hexagonal islands with corners located on the herringbone stripes, has a strong resistance to oxidation by O{sub 2} and NO{sub 2}. Star-like coplanar structures seen at the intersection of six dislocation stripes are the preferential nucleation sites for the hexagonal islands.},
doi = {10.1021/jp064366v},
journal = {Journal of Physical Chemistry C},
number = ,
volume = 111,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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