ESR and HRTEM Study of Carbon-Coated Nanocrystalline MgO Full article
| Journal |
The Journal of Physical Chemistry B
ISSN: 1520-6106 , E-ISSN: 1520-5207 |
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| Output data | Year: 2004, Volume: 108, Number: 10, Pages: 3140-3144 Pages count : 5 DOI: 10.1021/jp036307c | ||||
| Tags | Adsorption; Aerogels; Aromatic compounds; Catalysis; Chemical vapor deposition; Graphite; Nanostructured materials; Paramagnetic resonance; Pyrolysis; Solvents; Surface structure; Thermal effects | ||||
| Authors |
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| Affiliations |
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Funding (4)
| 1 | Civilian Research and Development Foundation | RC1-2340-NO-02 |
| 2 | Russian Foundation for Basic Research | 03-03-33178 |
| 3 | Council for Grants of the President of the Russian Federation | НШ-2120.2003.3 |
| 4 | Council for Grants of the President of the Russian Federation | НШ-1140.2003.3 |
Abstract:
Carbon-coated nanocrystalline MgO samples were prepared by butadiene pyrolysis at 500 °C over aerogel-prepared MgO samples. Samples with carbon loadings of 1.2, 3.2, 5.0, 10.0, and 15.9 wt % were prepared. Initial carbon formation rate was about 2 wt % per hour. According to HRTEM, the structure of the mineral component in the carbon-mineral materials was not altered by the carbon deposition. At low loading of carbon, it was found to deposit only inside the MgO aggregates 5−10 nm from their outside surface, forming thin individual bands 1.5−2 nm long. At the highest loading, carbon deposits form three-dimensional graphite-like multilayer structures filling the pore volume of the MgO aggregates and cover the outside surface of the aggregates with a thin monolayer coating. A single symmetric Lorentzian line with g = 2.0029 attributable to carbon deposits has been observed in the ESR spectra of the carbon-mineral materials. It gradually narrows from 5.0 to 1.9 G as the carbon loading increases from 1.2 to 15.9 wt %. Nitroxyl radicals formed after dinitrobenzene adsorption on MgO nanocrystals have been used as a spin probe for estimation of the concentration of strong basic sites present on the surface of the carbon-mineral materials and degree of their coverage with carbon. The sample with the carbon loading of 15.9 wt % has practically all such sites blocked with carbon, while samples with carbon concentration between 5 and 10 wt % seem to be the most promising candidates for practical application as destructive adsorbents.
Cite:
Heroux D.S.
, Volodin A.M.
, Zaikovski V.I.
, Chesnokov V.V.
, Bedilo A.F.
, Klabunde K.J.
ESR and HRTEM Study of Carbon-Coated Nanocrystalline MgO
The Journal of Physical Chemistry B. 2004. V.108. N10. P.3140-3144. DOI: 10.1021/jp036307c WOS Scopus РИНЦ ANCAN OpenAlex
ESR and HRTEM Study of Carbon-Coated Nanocrystalline MgO
The Journal of Physical Chemistry B. 2004. V.108. N10. P.3140-3144. DOI: 10.1021/jp036307c WOS Scopus РИНЦ ANCAN OpenAlex
Dates:
| Submitted: | Aug 5, 2003 |
| Published online: | Feb 12, 2004 |
| Published print: | Mar 1, 2004 |
Identifiers:
| Web of science: | WOS:000220093900005 |
| Scopus: | 2-s2.0-1842427872 |
| Elibrary: | 13460790 |
| Chemical Abstracts: | 2004:112369 |
| Chemical Abstracts (print): | 140:310049 |
| OpenAlex: | W1968827037 |