Aberration-corrected STEM Imaging of ag on γ-Al2O3

被引：7

作者：

Blom, Douglas A. ^{[1
]}

Allard, Lawrence F. ^{[1
]}

Narula, Chaitanya K. ^{[1
]}

Moses-DeBusk, Melanie J. ^{[1
]}

机构：

[1] Oak Ridge Natl Lab, Mat Sci & Technol Div, Oak Ridge, TN 37831 USA

来源：

MICROSCOPY AND MICROANALYSIS | 2008年 / 14卷 / 01期

关键词：

aberration-corrected scanning transmission electron microscopy; high-angle annular dark-field imaging; lean NOx catalyst; single-atom imaging; atomic resolution; ex situ STEM;

D O I：

10.1017/S143192760808015X

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Ag on gamma-alumina is a promising catalyst for hydrocarbon selective catalytic reduction in lean-burn gasoline and diesel engines for transportation applications. Although much is known about the mechanism of NOx reduction and the various intermediates, little agreement exists on the nature of the active silver species. In the present work, aberration-corrected STEM has provided new information about the nature of Ag on alumina both as impregnated and following treatments at various temperatures with exposure to simulated exhaust gas. Ex situ techniques have provided new insights into the evolution of Ag on alumina following exposure to temperature and simulated exhaust gas.

引用

页码：98 / 103

页数：6

共 18 条

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