Active role of oxide support during CO oxidation at Au/MgO

被引：412

作者：

Molina, LM ^{[1
]}

Hammer, B

机构：

[1] Aarhus Univ, iNANO, DK-8000 Aarhus C, Denmark

[2] Aarhus Univ, Dept Phys & Astron, DK-8000 Aarhus C, Denmark

来源：

PHYSICAL REVIEW LETTERS | 2003年 / 90卷 / 20期

关键词：

D O I：

10.1103/PhysRevLett.90.206102

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The oxidation of CO at MgO supported gold aggregates is studied by means of density functional theory calculations. In addition to serving as a structural promoter holding the gold particles, the supporting oxide also takes an active role in the bonding and activation of adsorbates bound to the gold. The oxide stabilizes a peroxolike reaction intermediate, CO.O-2, and causes steric repulsion to CO. The most reactive site at Au/MgO appears where the gold shelters the MgO thereby creating a cavity where several low-coordinated Au atoms and Mg2+ cations from the substrate can interact simultaneously with an adsorbate.

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页码：4 / 206102

页数：4

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