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Aberration-Corrected STEM Imaging of Ag on γ-Al2O3

Published online by Cambridge University Press:  21 December 2007

Douglas A. Blom ,
Lawrence F. Allard ,
Chaitanya K. Narula  and
Melanie J. Moses-DeBusk
Douglas A. Blom
Affiliation:
Oak Ridge National Laboratory, Materials Science & Technology Division, Oak Ridge, TN 37831-6064, USA
Lawrence F. Allard
Affiliation:
Oak Ridge National Laboratory, Materials Science & Technology Division, Oak Ridge, TN 37831-6064, USA
Chaitanya K. Narula
Affiliation:
Oak Ridge National Laboratory, Materials Science & Technology Division, Oak Ridge, TN 37831-6064, USA
Melanie J. Moses-DeBusk
Affiliation:
Oak Ridge National Laboratory, Materials Science & Technology Division, Oak Ridge, TN 37831-6064, USA
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Abstract

Ag on γ-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.

Keywords

aberration-corrected scanning transmission electron microscopyhigh-angle annular dark-field imaginglean NOx catalystsingle-atom imagingatomic resolutionex situ STEM
Type
Research Article
Information
Microscopy and Microanalysis , Volume 14 , Issue 1: Special Issue: Materials Research in an Aberration-Free Environment , February 2008 , pp. 98 - 103
Copyright
© 2008 Microscopy Society of America

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References

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