Electronic Structure of Oxygen Radicals on the Surface of VOx/TiO2 Catalysts and Their Role in Oxygen Isotopic Exchange Full article
| Journal |
The Journal of Physical Chemistry C
ISSN: 1932-7447 , E-ISSN: 1932-7455 |
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| Output data | Year: 2013, Volume: 117, Number: 28, Pages: 14701-14709 Pages count : 9 DOI: 10.1021/jp404921d | ||
| Tags | Activation energy; Catalysts; Catalytic oxidation; Electronic structure; Isotopes; Paramagnetism; Three dimensional; Titanium dioxide | ||
| Authors |
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| Affiliations |
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Funding (2)
| 1 | Federal Agency for Scientific Organizations | V.45.3.2. |
| 2 | Russian Foundation for Basic Research | 12-03-00905 |
Abstract:
The electronic structure of oxygen radicals formed by adsorption of gas-phase oxygen on partially reduced sites of supported vanadium oxide catalyst V4+Ox/TiO2 has been studied by periodic DFT. The unpaired electron density in the radicals is transferred from the paramagnetic V4+(3d1) ion to the adsorbed oxygen atoms resulting in the formation of surface oxygen radicals: atomic O–, superoxide O2–, and ozonide O3–. These radical species exhibit higher reactivity compared to the surface oxygen species stabilized on fully oxidized diamagnetic V5+(3d0) ions. Oxygen isotopic exchange over O– radicals has been investigated by the climbing image nudged elastic band (CI-NEB) method. We show that molecular oxygen can exchange with the lattice oxygen of the surface paramagnetic radicals V5+O– with low activation energy of about 14 kcal/mol, close to the value experimentally observed for some heterolytic R1 oxygen exchange reactions on vanadia catalysts. The obtained data suggest that O– radicals formed as short-lived intermediates at elevated temperatures are likely to be the active sites of the oxygen exchange following the R1 mechanism. The properties of oxygen radicals and their possible role in catalytic oxidation processes taking place over bulk and supported metal oxide catalysts are discussed. It is suggested that oxygen radicals can be the active species in catalytic oxidation reactions.
Cite:
Avdeev V.I.
, Bedilo A.F.
Electronic Structure of Oxygen Radicals on the Surface of VOx/TiO2 Catalysts and Their Role in Oxygen Isotopic Exchange
The Journal of Physical Chemistry C. 2013. V.117. N28. P.14701-14709. DOI: 10.1021/jp404921d WOS Scopus РИНЦ ANCAN OpenAlex
Electronic Structure of Oxygen Radicals on the Surface of VOx/TiO2 Catalysts and Their Role in Oxygen Isotopic Exchange
The Journal of Physical Chemistry C. 2013. V.117. N28. P.14701-14709. DOI: 10.1021/jp404921d WOS Scopus РИНЦ ANCAN OpenAlex
Dates:
| Submitted: | May 20, 2013 |
| Accepted: | Jun 12, 2013 |
| Published online: | Jul 3, 2013 |
| Published print: | Jul 18, 2013 |
Identifiers:
| Web of science: | WOS:000322150100028 |
| Scopus: | 2-s2.0-84880532799 |
| Elibrary: | 20444251 |
| Chemical Abstracts: | 2013:955842 |
| Chemical Abstracts (print): | 159:173445 |
| OpenAlex: | W2335501310 |