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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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References

1. Singhal, A., Yang, J.C. and Gibson, J.M., STEM-based mass spectroscopy of Re clusters. Ultramicroscopy, 1997. 67: p. 191206.Google Scholar
2. Yang, J.C., Bradley, S., Yeadon, M. and Gibson, J.M., Nano-sized catalysts investigated by a STEM-based Mass Spectroscopic Technique. EMAG, 1998. 143: p. 383386.Google Scholar
3. Treacy, M.M.J. and Rice, S.B., Catalyst particle sizes from Rutherford scattered intensities. Journal of Microscopy, 1989. 156(2): p. 211234.Google Scholar
4. Poltorak, O.M. and Boronin, V.S., Mitohedry - A new method of studying active centres in crystalline catalysts. Russian Journal of Physical Chemistry, 1966. 40(11): p. 14361445.Google Scholar
5. Hansen, M., Constitution of Binary Alloys. 2 ed. 1958: McGraw-Hill.Google Scholar
6. Nashner, M.S., Frenkel, A.I., Adler, D.L., Shapley, J.R. and Nuzzo, R.G., Structural Characterization of Carbon-Supported Pt-Ru Nanoparticles from the Molecular Cluster Precursor PtRu5C(CO)16. J. of Am. Cer. Soc., 1998. to be published.Google Scholar