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Theoretical Studies of Pt Chemisorption on γ Al2O3.

Published online by Cambridge University Press:  28 February 2011

J. J. Low  and
D. E. Ellis
J. J. Low
Affiliation:
Allied-Signal Engineered Materials Research Center, 50 East Algonquin Rd., Box 5016,Des Plaines, IL 60017-5016
D. E. Ellis
Affiliation:
Northwestern University, Evanston, I1 60201
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Abstract

Generalized Valence Bond (GVB) and Local Density Functional (LDF) calculations were carried out to explore the influence of electronic structure on the metal-support interaction in Pt/γAl2O3. On the basis of GVB calculations it was found that ethylene can form either di-σ- or π complexes on Pt depending on the oxidation state of the metal. The LDF calculations showed that chemisorbed Pt transfers charge to γ-Al2O3. These results and experimental observations led us to propose a model of the metal-support interaction in which the Pt exists in two oxidation states for reduced Pt/ Al2O3 catalysts.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 111: Symposium O – Microstructure and Properties of Catalysts , 1987 , 347
Copyright
Copyright © Materials Research Society 1988

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