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Oxygen Desorption from Polycrystalline Palladium: Thermal Desorption of O2 from a Chemisorbed Layer of Oads in the Course of the Decomposition of PdO Surface Oxide and in the Release of Oxygen from the Bulk of Palladium Full article

Journal Kinetics and Catalysis
ISSN: 0023-1584 , E-ISSN: 1608-3210
Output data Year: 2010, Volume: 51, Number: 3, Pages: 416-427 Pages count : 12 DOI: 10.1134/S0023158410030158
Tags Pd(100); OXIDATION; Pd(111); ADSORPTION; KINETICS
Authors Salanov A.N. 1 , Suprun E.A. 1
Affiliations
1 Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences

Abstract: The desorption of oxygen from polycrystalline palladium (Pd(poly)) was studied using temperature-programmed desorption (TPD) at 500–1300 K and the amounts of oxygen absorbed by palladium (n) from 0.05 to 50 monolayers. It was found that the desorption of O2 from Pd(poly), which occurred from a chemisorbed oxygen layer (Oads), in the release of oxygen from a near-surface metal layer in the course of the decomposition of PdO surface oxide, and in the release of oxygen from the bulk of palladium (Oabs), was governed by repulsive interactions between Oads atoms and the formation and decomposition of Oads-Pd*-Oabs structures (Pd* is a surface palladium atom). At θ ≤ 0.5, the repulsive interactions between Oads atoms (ɛaa = 10 kJ/mol) resulted in the desorption of O2 from Pd(poly) at 650–950 K. At 0.5 ≤ n ≤ 1.0, the release of inserted oxygen from a near-surface palladium layer occurred during TPD in the course of the migration of Oabs atoms to the surface and the formation-decomposition of Oads-Pd*-Oabs structures. As a result, the desorption of O2 occurred in accordance with a first-order reaction with a thermal desorption (TD) peak at T max ∼ 700 K. At 1.0 ≤ n ≤ 2.0, the decomposition of PdO surface oxide occurred at a constant surface cover-age with oxygen during TPD in the course of the formation-decomposition of Oads-Pd*-Oabs structures. Because of this, the desorption of O2 occurred in accordance with a zero-order reaction at low temperatures with a TD peak at T max ∼ 675 K. At 1.0 ≤ n ≤ 50, oxygen atoms diffused from deep palladium layers in the course of TPD and arrived at the surface at high temperatures. As a result, O2 was desorbed with a high-temperature TD peak at T > 750 K.
Cite: Salanov A.N. , Suprun E.A.
Oxygen Desorption from Polycrystalline Palladium: Thermal Desorption of O2 from a Chemisorbed Layer of Oads in the Course of the Decomposition of PdO Surface Oxide and in the Release of Oxygen from the Bulk of Palladium
Kinetics and Catalysis. 2010. V.51. N3. P.416-427. DOI: 10.1134/S0023158410030158 WOS Scopus РИНЦ ANCAN OpenAlex
Original: Саланов А.Н. , Супрун Е.А.
Исследование десорбции кислорода с поликристаллического палладия. Термодесорбция О2 из хемосорбционного слоя Оадс, в ходе разложения поверхностного оксида PdO и при выделении кислорода из объема палладия
Кинетика и катализ. 2010. Т.51. №3. С.435-446. РИНЦ
Dates:
Submitted: Mar 3, 2009
Published print: Jun 1, 2010
Published online: Jun 24, 2010
Identifiers:
Web of science: WOS:000281104600015
Scopus: 2-s2.0-77955721514
Elibrary: 15336816
Chemical Abstracts: 2010:788069
Chemical Abstracts (print): 153:652177
OpenAlex: W2027214411
Citing:
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Web of science 4
Scopus 4
Elibrary 4
OpenAlex 4
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