1. Experimental and theoretical study of oxygen adsorption structures on Ag(111)
- Author
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Schnadt, Joachim, Knudsen, Jan, Hu, Xiao Liang, Michaelides, Angelos, Vang, Ronnie T., Reuter, Karsten, Li, Zheshen, Lægsgaard, Erik, Scheffler, Matthias, and Besenbacher, Flemming
- Subjects
Condensed Matter - Materials Science - Abstract
The oxidized Ag(111) surface has been studied by a combination of experimental and theoretical methods, scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), and density functional theory (DFT). A large variety of different surface structures is found, depending on the detailed preparation conditions. The observed structures fall into four classes: (a) individually chemisorbed atomic oxygen atoms, (b) three different oxygen overlayer structures, including the well-known p(4 x 4) phase, formed from the same Ag$_6$ and Ag$_{10}$ building blocks, (c) a c(4 x 8) structure not previously observed, and (d) at higher oxygen coverages structures characterized by stripes along the high-symmetry directions of the Ag(111) substrate. Our analysis provides a detailed explanation of the atomic-scale geometry of the Ag$_6$/Ag$_{10}$ building block structures, and the c(4 x 8) and stripe structures are discussed in detail. The observation of many different and co-existing structures implies that the O/Ag(111) system is characterized by a significantly larger degree of complexity than previously anticipated, and this will impact our understanding of oxidation catalysis processes on Ag catalysts., Comment: 12 pages, 9 figures; peer-reviewed and published version
- Published
- 2009
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