The Partial Oxidation of Methane Over Pd/Al2O3 Catalyst Nanoparticles Studied In-Situ by Near Ambient-Pressure X-ray Photoelectron Spectroscopy
| Autor: | Georg Held, Ethan J. Crumlin, Rachel Price, Sana Rani, Chanan Euaruksakul, Tuǧçe Eralp-Erden, Richard A.P. Smith, Sonia Garcia, Liam Deacon |
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| Rok vydání: | 2016 |
| Předmět: |
Chemistry(all)
Inorganic chemistry Oxide Analytical 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 Chemical state chemistry X-ray photoelectron spectroscopy Oxidation state Anaerobic oxidation of methane Partial oxidation 0210 nano-technology Palladium |
| Zdroj: | Topics in Catalysis. 59:516-525 |
| ISSN: | 1572-9028 1022-5528 |
| Popis: | Near ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS) is used to study the chemical state of methane oxidation catalysts in-situ. Al2O3–supported Pd catalysts are prepared with different particle sizes ranging from 4 to 10 nm. These catalysts were exposed to conditions similar to those used in the partial oxidation of methane (POM) to syn-gas and simultaneously monitored by NAP-XPS and mass spectrometry. NAP-XPS data show changes in the oxidation state of the palladium as the temperature increases, from metallic Pd0 to PdO, and back to Pd0. Mass spectrometry shows an increase in CO production whilst the Pd is in the oxide phase, and the metal is reduced back under presence of newly formed H2. A particle size effect is observed, such that CH4 conversion starts at lower temperatures with larger sized particles from 6 to 10 nm. We find that all nanoparticles begin CH4 conversion at lower temperatures than polycrystalline Pd foil. |
| Databáze: | OpenAIRE |
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