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Quantitative Energy-Dispersive X-Ray Analysis of Catalyst Nanoparticles Using a Partial Cross Section Approach

Published online by Cambridge University Press:  12 January 2016

Katherine E. MacArthur*
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
Thomas J. A. Slater
Affiliation:
Materials Science Centre, University of Manchester, Manchester M13 9PL, UK
Sarah J. Haigh
Affiliation:
Materials Science Centre, University of Manchester, Manchester M13 9PL, UK
Dogan Ozkaya
Affiliation:
Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading RG4 9NH, Reading, UK
Peter D. Nellist
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
Sergio Lozano-Perez
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
*
*Corresponding author.[email protected]
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Abstract

The new generation of energy-dispersive X-ray (EDX) detectors with higher count rates than ever before, paves the way for a new approach to quantitative elemental analysis in the scanning transmission electron microscope. Here we demonstrate a method of calculating partial cross sections for use in quantifying EDX data, beneficial especially because of the simplicity of its implementation. Applying this approach to acid-leached PtCo catalyst nanoparticles leads to quantitative determination of the Pt surface enrichment.

Type
Materials Applications
Copyright
© Microscopy Society of America 2016 

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