In situ XPS studies of kinetic hysteresis in methane oxidation over Pt/γ-Al 2 O 3 catalysts
| Autor: | Valentin N. Parmon, Igor P. Prosvirin, Igor A. Chetyrin, I. Yu. Pakharukov, Valery I. Bukhtiyarov |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Chemistry
Inorganic chemistry chemistry.chemical_element 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Catalysis Methane 0104 chemical sciences chemistry.chemical_compound Hysteresis X-ray photoelectron spectroscopy Oxidation state Anaerobic oxidation of methane Limiting oxygen concentration 0210 nano-technology Platinum |
| Zdroj: | Catalysis Today. 278:135-139 |
| ISSN: | 0920-5861 |
| DOI: | 10.1016/j.cattod.2016.05.004 |
| Popis: | Recently, we have shown that methane oxidation over Pt/Al 2 O 3 catalysts can proceed via two stable stationary regimes with low and high catalytic activity under identical external conditions. The switching between the regimes occurs abruptly and depends on the oxygen concentration and direction of its change at the constant methane concentration. In situ X-ray photoelectron spectroscopy (XPS) coupled with mass spectrometry was used to correlate changes in the oxidation state of platinum with catalytic activity in the methane oxidation. In situ XPS experiments confirmed the presence of the kinetic hysteresis even at the sub-millibar pressure range (∼0.01 mbar). Analysis of the XPS spectra showed that the catalyst activation is associated with partial reduction of the supported platinum. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect