Adsorption and temperature-dependent decomposition of SO2 on Ni(110): an XPS and XAFS study
| Autor: | Martin Polcik, Daniele Cocco, Giovanni Comelli, J. Haase, B. Brena, Giorgio Paolucci, L. Wilde |
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| Přispěvatelé: | L., Wilde, M., Polcik, J., Haase, B., Brena, D., Cocco, Comelli, Giovanni, G., Paolucci |
| Rok vydání: | 1998 |
| Předmět: |
Decomposition
Analytical chemistry chemistry.chemical_element Sulphur dioxide Surfaces and Interfaces Condensed Matter Physics Surfaces Coatings and Films X-ray absorption fine structure Bond length Nickel Adsorption chemistry X-ray photoelectron spectroscopy Chemisorption Phase (matter) Nichel Materials Chemistry Absorption (chemistry) |
| Zdroj: | Surface Science. 405:215-227 |
| ISSN: | 0039-6028 |
| Popis: | The adsorption and temperature-dependent decomposition of SO 2 on Ni(110) has been studied by core-level photoemission and X-ray absorption fine structure measurements. The analysis shows that on adsorption at 160 K SO 2 partly decomposes, leaving SO 3 and atomic S on the surface. Two different, nearly flat-lying SO 2 species are observed which correspond to long-bridge and short-bridge S sites. The S atoms of co-adsorbed atoms of SO 3 occupy short-bridge sites with the C 3 axis of SO 3 being oriented approximately perpendicular to the surface, whereas atomic S is located in two-fold hollow sites. The average S–Ni bond length of all S-containing species measures 2.30±0.04 A. On heating this co-adsorption phase to room temperature, SO 2 completely disappears from the surface, the coverages of adsorbed SO 3 and S increase and small amounts of atomic O show up. On further heating, SO 3 decomposes completely, increasing the amounts of atomic S and O on the surface while SO 2 is observed in the gas phase. At still higher temperatures, only atomic S remains adsorbed in a quasi five-fold coordinated site with an average S–Ni bond length of 2.26±0.04 A. |
| Databáze: | OpenAIRE |
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