Direct Observation of the Reversible Changes of the Morphology of Pt Nanoparticles under Gas Environment

被引：65

作者：

Cabie, M. ^{[1
,2
]}

Giorgio, S. ^{[1
,2
]}

Henry, C. R. ^{[1
,2
]}

Axet, M. Rosa ^{[3
,4
]}

Philippot, K. ^{[3
,4
]}

Chaudret, B. ^{[3
,4
]}

机构：

[1] CNRS, CINaM, F-13288 Marseille 9, France

[2] Univ Aix Marseille 2, Marseille, France

[3] CNRS, Chim Coordinat Lab, F-31077 Toulouse, France

[4] Univ Toulouse, UPS, INPT, LCC, F-31077 Toulouse, France

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2010年 / 114卷 / 05期

关键词：

SURFACE-ENERGY ANISOTROPY; ELECTRON-MICROSCOPY; SHAPE CHANGES; PD PARTICLES; PLATINUM; ADSORPTION; ADSORBATE; OXIDATION; CATALYSTS;

D O I：

10.1021/jp906721g

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：

Large faceted Pt particles prepared in Solution were in situ observed by ETEM (Environmental Transmission Electron Microscopy) during oxidation - reduction cycles. Reversible shape transformations were observed with the increase or decrease of the ratio of (111) faces to (001) faces in H-2 and O-2 respectively, at pressures of a few mbars. Under Hydrogen, the shape is relatively close to the Wulff shape of an fcc crystal under vacuum, while under oxygen, the (001) faces extend and the (111) faces shrink due to a stronger adsorption of oxygen on the more open (100) faces. Going from hydrogen to oxygen, the surface energy anisotropy is inverted.

引用

页码：2160 / 2163

页数：4

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