Characterization of Electron-Donor and Electron-Acceptor Sites on the Surface of Sulfated Alumina Using Spin Probes
| Autor: | Alexandra A. Rybinskaya, Alexander F. Bedilo, Dmitrii A. Medvedev, Ekaterina I. Shuvarakova |
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| Rok vydání: | 2014 |
| Předmět: |
chemistry.chemical_classification
Anthracene Inorganic chemistry Hexafluorobenzene Electron donor Electron acceptor Surfaces Coatings and Films Electronic Optical and Magnetic Materials Spin probe chemistry.chemical_compound General Energy Adsorption chemistry Hexamethylbenzene Physical and Theoretical Chemistry Sulfate |
| Zdroj: | The Journal of Physical Chemistry C. 118:15779-15794 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/jp503523k |
| Popis: | Electron-donor sites on the surface of γ-Al2O3 modified with different amounts of sulfates were characterized using 1,3,5-trinitrobenzene as a spin probe. The concentration of 1,3,5-trinitrobezene radical anions formed on the surface electron-donor sites was found to decrease when the sulfate concentration and the surface acidity increased. Electron-acceptor sites of different strengths were studied using the formation of radical cations after adsorption of donor aromatic molecules with different ionization potentials. Changes in the intensity of the EPR signal observed after adsorption of hexafluorobenzene, toluene, hexamethylbenzene, and anthracene on the surface of sulfated alumina samples with different sulfate concentrations were analyzed. Modification of γ-Al2O3 with sulfates was found to result in the formation of strong electron-acceptor sites capable of ionizing toluene and hexamethylbenzene to their radical cations. Such sites were observed on the samples with the sulfate concentrations 4 wt % o... |
| Databáze: | OpenAIRE |
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