Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-28T17:00:32.704Z Has data issue: false hasContentIssue false
  • English
  • Français

Visibility of Small Metalllic Catalyst Particles in High-Resolution Secondary and Backscattered Electron Images

Published online by Cambridge University Press:  02 July 2020

Jingyue Liu
Jingyue Liu*
Affiliation:
Science and Technology, Monsanto Company, St. Louis, M063167
Get access

Extract

Metallic nanoparticles finely dispersed onto high surface-area supports play an important role in heterogeneous catalysis. The performance of a supported metal catalyst can be directly related to the size and spatial distribution of the metallic nanoparticles. With the recent development of highresolution SEM instruments, it is now possible to observe nanoparticles in a field emission SEM. At low voltages, surface details of catalyst supports as well as metallic nanoparticles can be observed. The particle contrast in low voltage SEM images, however, is still not well understood. We have previously shown that the contrast of metallic particles can be enhanced if a small positive potential is applied to the sample. It is suggested that backscattered electrons (BE) significantly contribute to the visibility of metallic nanoparticles in high-resolution SE images. In this paper, we report further study on the origin of particle contrast in high-resolution SE images.

Figure 1 shows a set of SE images of the same area of a carbon supported Pt catalyst.

Type
A. Howie Symposium: Celebration of Pioneering Electron Microscopy
Information
Microscopy and Microanalysis , Volume 5 , Issue S2: Proceedings: Microscopy & Microanalysis '99, Microscopy Society of America 57th Annual Meeting, Microbeam Analysis Society 33rd Annual Meeting, Portland, Oregon August 1-5, 1999 , August 1999 , pp. 720 - 721
Copyright
Copyright © Microscopy Society of America

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Liu, J., Proceedings 14th International Congress on Electron Microscopy (1998) 399.Google Scholar
2.Liu, J.et al., Microscopy & Microanalysis 3 (Supplement 2) (1997) 1223.CrossRefGoogle Scholar
3.Darji, R.and Howie, A., Micron 28 (1997) 95.CrossRefGoogle Scholar