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Three Dimensional Ultra-Small Pt Clusters on Carbon As Studied by A Novel Stem Technique

Published online by Cambridge University Press:  15 February 2011

J. C. Yang
Affiliation:
Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801
S. Bradley
Affiliation:
UOP, 50 East Algonquin Road, Des Plaines, IL 60017
J. M. Gibson
Affiliation:
Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801
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Abstract

Very high angle (∼ 100mrad) annular dark-field (HAADF) images in a dedicated scanning transmission electron microscope (STEM) can be used to quantitatively measure the number of atoms in a cluster on a support material. We have developed a computer program which will automatically find the location of the particles and then integrate the intensity to find the number of atoms per cluster. We have examined ultra-small Pt clusters on a C substrate by this novel mass-spectroscopic technique. We discovered that the Pt clusters maintain their three-dimensional shape, and are probably spherical in shape.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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