Molecular Mechanism of Oxygen Exchange over Supported Vanadium Oxide Catalyst VOx/TiO2 Научная публикация
| Журнал |
The Journal of Physical Chemistry C
ISSN: 1932-7447 , E-ISSN: 1932-7455 |
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| Вых. Данные | Год: 2013, Том: 117, Номер: 6, Страницы: 2879-2887 Страниц : 9 DOI: 10.1021/jp311322b | ||
| Ключевые слова | Activation energy; Catalysts; Catalytic oxidation; Electronic structure; Isotopes; Paramagnetism; Three dimensional; Titanium dioxide | ||
| Авторы |
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| Организации |
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Информация о финансировании (2)
| 1 | Федеральное агентство научных организаций России | V.45.3.2. |
| 2 | Российский фонд фундаментальных исследований | 12-03-00905 |
Реферат:
Detailed molecular mechanisms of oxygen isotopic exchange over VOx/TiO2 catalyst following the R0, R1, and R2 mechanisms were studied using periodic DFT analysis of possible pathways by the CI-NEB method. The electronic structures of surface VOx species formed on the VOx/TiO2 model surface after interaction of molecular oxygen with fully oxidized O═V5+–O–V5+═O sites and reduced V3+–O–V3+ sites were analyzed. We found a number of metastable surface structures that are potential intermediates in the exchange reaction pathways. We present evidence that adsorption of two gas-phase oxygen molecules on a reduced V3+–O-V3+ site leads to the formation of a superoxide complex, followed by its transformation into a peroxide complex with low activation energy about E* = 0.04 eV (0.92 kcal/mol). Subsequent transformation of this surface superoxide-peroxide species follows the Langmuir–Hinshelwood mechanism without participation of lattice oxygen along the R0 reaction pathway. We demonstrate that adsorption of molecular oxygen on fully oxidized O═V5+–O–V5+═O sites results in the formation of either monodentate V<(O3) or bidentate V<(O3)>V surface ozonide species. Their subsequent transformations result in oxygen isotopic exchange following the R1 or R2 mechanisms with the activation energies in the range of 1.44 to 1.64 eV for the R1 mechanism and 1.81 eV for the R2 one. These processes follow the Eley–Rideal mechanism with participation of one or two lattice oxygen atoms, correspondingly.
Библиографическая ссылка:
Avdeev V.I.
, Bedilo A.F.
Molecular Mechanism of Oxygen Exchange over Supported Vanadium Oxide Catalyst VOx/TiO2
The Journal of Physical Chemistry C. 2013. V.117. N6. P.2879-2887. DOI: 10.1021/jp311322b WOS Scopus РИНЦ CAPlusCA OpenAlex
Molecular Mechanism of Oxygen Exchange over Supported Vanadium Oxide Catalyst VOx/TiO2
The Journal of Physical Chemistry C. 2013. V.117. N6. P.2879-2887. DOI: 10.1021/jp311322b WOS Scopus РИНЦ CAPlusCA OpenAlex
Даты:
| Поступила в редакцию: | 16 нояб. 2012 г. |
| Принята к публикации: | 15 янв. 2013 г. |
| Опубликована online: | 30 янв. 2013 г. |
| Опубликована в печати: | 14 февр. 2013 г. |
Идентификаторы БД:
| Web of science: | WOS:000315181800058 |
| Scopus: | 2-s2.0-84873953626 |
| РИНЦ: | 20434352 |
| Chemical Abstracts: | 2013:111796 |
| Chemical Abstracts (print): | 158:227190 |
| OpenAlex: | W2317467103 |