The Quest for Stability: Structural Dependence of Rh(111) on Oxygen Coverage at Elevated Temperature
| Autor: | Noelle T Wands, Rachael G. Farber, Daniel R. Killelea, Eleanor C. N. Oskorep, Marie E. Turano, Erin V. Iski |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Chemistry
Inorganic chemistry Oxide chemistry.chemical_element 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Oxygen 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Catalysis Metal chemistry.chemical_compound General Energy visual_art visual_art.visual_art_medium Structural dependence Atomic oxygen Surface structure Limiting oxygen concentration Physical and Theoretical Chemistry 0210 nano-technology |
| Zdroj: | The Journal of Physical Chemistry C. 121:10470-10475 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/acs.jpcc.7b02738 |
| Popis: | 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. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|