In situ oxidation study of MgO(100) supported Pd nanoparticles

被引：37

作者：

Kasper, N. ^{[1
]}

Stierle, A. ^{[1
]}

Nolte, P. ^{[1
]}

Jin-Phillipp, Y. ^{[1
]}

Wagner, T. ^{[1
]}

de Oteyza, D. G. ^{[1
]}

Dosch, H. ^{[1
]}

机构：

[1] Max Planck Inst Met Res, D-70569 Stuttgart, Germany

来源：

SURFACE SCIENCE | 2006年 / 600卷 / 14期

关键词：

palladium; magnesium oxide; nanoparticles; oxidation; x-ray scattering; diffraction and reflection;

D O I：

10.1016/j.susc.2006.05.030

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

We have investigated the oxidation behavior of Pd nanoparticles grown epitaxially on MgO(1 0 0) single crystal substrates. We find that the interaction of oxygen with octahedral Pd nanoparticles at 500 K can be subdivided in three stages: above 10(-6) mbar O-2 pressure, the particles start to flatten; above 10(-3) mbar, the particles begin to shrink laterally and to be less truncated at the corners. The formation of epitaxial bulk PdO sets in at oxygen pressures above 0.1 mbar, which is accompanied by a continuous shrinkage of the Pd particles. Our results point to a novel nanoparticle oxidation mechanism: the Pd particles act as dissociation centers for O-2 and serve at the same time as source for Pd atoms resulting in epitaxial PdO growth on MgO(1 0 0). (c) 2006 Elsevier B.V. All rights reserved.

引用

页码：2860 / 2867

页数：8

共 29 条

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