Sciact
  • EN
  • RU

Oscillations in the Carbon Monoxide Oxidation on Platinum Surfaces Observed by Field Electron Microscopy Научная публикация

Конференция 39th International Field Emission Symposium
10-14 авг. 1992 , Halifax, Nova Scotia
Журнал Applied Surface Science
ISSN: 0169-4332
Вых. Данные Год: 1993, Том: 67, Номер: 1-4, Страницы: 198-205 Страниц : 8 DOI: 10.1016/0169-4332(93)90312-Y
Авторы Gorodetskii V. 1,2 , Block J.H. 1 , Drachsel W. 1 , Ehsasi M. 1
Организации
1 Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-0, D-1000 Berlin 33, Germany
2 Boreskov Institute of Catalysis of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
Реферат: Platinum field emitter tips ((111)-, (001)-, and (012)-oriented) are used to investigate local surface properties during the oscillatory regime of the CO-oxidation at T = 430–480 K and partial pressures po2≈5×10-4 mbar and pCO≈5×10-5 mbar. Changes in surface coverage - and catalytic activity - are indicated by variations of the local work function and field emission current. Self-sustaining isothermal oscillations could be observed on different crystal planes. (i) A fast “switching on” of emission currents is initially noticed when the oxygen adsorption layer is transferred into a CO-layer. Starting - after a certain induction period - from the (011)-region the oxygen side is quickly switched into the CO-side, which slowly returns back to the catalytically active oxygen side. (ii) The formation of reactive wave fronts starts in the (011)-region and propagates in the direction of (111)- and (100)-planes. The CO-wavefront and the O-wavefront move alternately in opposite directions and display different propagation velocities, which could be measured. The frequencies and amplitudes of oscillations critically depends on temperatures and partial pressures. Compared to single crystal planes a broadening and shift of oscillatory regimes in parameter space is noticed. In certain cases period doubling could be measured.
Библиографическая ссылка: Gorodetskii V. , Block J.H. , Drachsel W. , Ehsasi M.
Oscillations in the Carbon Monoxide Oxidation on Platinum Surfaces Observed by Field Electron Microscopy
Applied Surface Science. 1993. V.67. N1-4. P.198-205. DOI: 10.1016/0169-4332(93)90312-Y WOS Scopus РИНЦ CAPlusCA OpenAlex Sciact
Даты:
Поступила в редакцию: 10 авг. 1992 г.
Принята к публикации: 28 авг. 1992 г.
Опубликована в печати: 2 апр. 1993 г.
Опубликована online: 5 авг. 2002 г.
Идентификаторы БД:
Web of science: WOS:A1993KZ64700031
Scopus: 2-s2.0-0027224865
РИНЦ: 31104067
Chemical Abstracts: 1993:241598
Chemical Abstracts (print): 118:241598
OpenAlex: W2092304857
Sciact: 12320
Цитирование в БД:
БД Цитирований
Scopus 64
OpenAlex 60
Альметрики: