Loading…
The Quest for Stability: Structural Dependence of Rh(111) on Oxygen Coverage at Elevated Temperature
Recent studies have shown the importance of oxide surfaces in heterogeneously catalyzed reactions. Because of the difficulties in reproducibly preparing oxidized metal surfaces, it is often unclear what species are thermodynamically stable and what factors effect the oxide formation process. In this...
Saved in:
Published in: | Journal of physical chemistry. C 2017-05, Vol.121 (19), p.10470-10475 |
---|---|
Main Authors: | , , , , , |
Format: | Article |
Language: | English |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Recent studies have shown the importance of oxide surfaces in heterogeneously catalyzed reactions. Because of the difficulties in reproducibly preparing oxidized metal surfaces, it is often unclear what species are thermodynamically stable and what factors effect the oxide formation process. In this work, we show that the thermodynamically stable phases on Rh(111) after exposure to atomic oxygen are the (2×1)-O adlayer and the trilayer surface oxide, RhO2. Formation of RhO2 was facilitated by surface defects and elevated concentrations of dissolved O atoms in the subsurface region. As the concentration of subsurface O atoms decreased, the coverage of RhO2 decreased so that only the (2×1)-O adlayer was present on the surface. The importance of subsurface oxygen species in RhO2 formation and stability indicates a complex relationship between surface structure and subsurface oxygen concentration. |
---|---|
ISSN: | 1932-7447 1932-7455 |
DOI: | 10.1021/acs.jpcc.7b02738 |