The oblate morphology of supported PtRu{sub 5} on carbon black

• Published in: Materials characterization Vol. 51; no. 2-3
• Main Authors: Yang, Judith C., Bradley, Stephen, Gibson, J. Murray
• Format: Journal Article
• Language: English
• Published: United States 15-10-2003
• Subjects: CARBON BLACK; MATERIALS SCIENCE; MORPHOLOGY; NANOSTRUCTURES; PARTICLES; TRANSMISSION ELECTRON MICROSCOPY
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2003.09.013

We have examined supported PtRu{sub 5} nanoparticles by a variety of electron microscopy techniques, including high-resolution, analytical and a unique mass-spectroscopic electron microscopy technique. The absolute intensity from very high angle annular dark-field images in a dedicated scanning transmission electron microscope can be quantified to determine the number of atoms in a nanoparticle on a support material. Analytical electron microscopy results revealed that the relative Pt:Ru atomic concentration in a nanoparticle does not vary significantly from particle to particle. The average diameter of the nanoparticles was 1.56 nm, and the average number of atoms was measured to be 24 atoms per nanoparticle. The combination of these techniques indicates that the PtRu{sub 5} nanoparticles are oblate on the carbon black support.