| Autor: |
Matthew C, Patterson, Nathan D, Keilbart, Lucy W, Kiruri, Chad A, Thibodeaux, Slawo, Lomnicki, Richard L, Kurtz, E D, Poliakoff, Barry, Dellinger, Phillip T, Sprunger |
| Rok vydání: |
2014 |
| Předmět: |
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| Zdroj: |
Chemical physics. 422 |
| ISSN: |
0301-0104 |
| Popis: |
We have examined the formation of environmentally persistent free radicals (EPFRs) from phenol over alumina and titania using both powder and single-crystal samples. Electron paramagnetic resonance (EPR) studies of phenol adsorbed on metal oxide powders indicates radical formation on both titania and alumina, with both oxides forming one faster-decaying species (lifetime on the order of 50-100 hours) and one slower-decayng species (lifetimes on the order of 1000 hours or more). Electron energy loss spectroscopy (EELS) measurements comparing physisorbed phenol on single-crystal TiO2(110) to phenoxyl radicals on the same substrate indicate distinct changes in the π-π* transitions from phenol after radical formation. The identical shifts are observed from EELS studies of phenoxyl radicals on ultrathin alumina grown on NiAl(110), indicating that this shift in the π-π* transition may be taken as a general hallmark of phenoxyl radical formation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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