Hostname: page-component-8448b6f56d-xtgtn Total loading time: 0 Render date: 2024-04-25T04:59:18.936Z Has data issue: false hasContentIssue false
  • English
  • Français

Nanoscale characterization of Pd/TiO2 catalysts and Ag/TiO2 catalysts by electron holography

Published online by Cambridge University Press:  01 February 2011

Satoshi Ichikawa ,
Tomoki Akita ,
Kazuyuki Okazaki ,
Koji Tanaka  and
Masanori Kohyama
Satoshi Ichikawa
Affiliation:
ichikawa@nano.sigma.es.osaka-u.ac.jp, Osaka University, Organization for the Promotion of Research on Nanoscience and Nanotechnology, 1-1-H329, Machikaneyama, Toyonaka, Osaka, 560-0043, Japan, +81-6-6850-5754, +81-6-6850-5754
Tomoki Akita
Affiliation:
t-akita@aist.go.jp, National Institute of Advanced Industrial Science and Technology (AIST), Research Institute for Ubiquitous Energy Devices, Japan
Kazuyuki Okazaki
Affiliation:
k.okazaki@aist.go.jp, National Institute of Advanced Industrial Science and Technology (AIST), Research Institute for Ubiquitous Energy Devices, Japan
Koji Tanaka
Affiliation:
koji.tanaka@aist.go.jp, National Institute of Advanced Industrial Science and Technology (AIST), Research Institute for Ubiquitous Energy Devices, Japan
Masanori Kohyama
Affiliation:
m-kohyama@aist.go.jp, National Institute of Advanced Industrial Science and Technology (AIST), Research Institute for Ubiquitous Energy Devices
Get access

Abstract

Catalytic properties of noble metal catalysts are often caused by their nanostructures and the interaction between nano particles and oxides supports. We examine the mean inner potential of Pd particles in Pd/TiO2 catalyst and Ag particles in Ag/TiO2 catalysts using electron holography and HRTEM. And we compare the results of the Pd/TiO2 and Ag/TiO2 systems with our previous results of the Au/TiO2 and Pt/TiO2 systems. In the case of the Pd/TiO2 catalysts, when the size of Pd particle is smaller than 5nm, the mean inner potential of Pd changes to be higher than the calculated value of the mean inner potential which is thought to be higher than the experimental values of bulk Pd by 3-5V. The mean inner potential of Pd becomes to increase gradually as the size of the Pd particle decreases. The rate of the increment in the mean inner potential of Pd is lower than that of Au/TiO2 catalysts and Pt/TiO2 catalysts. On the other hand, in the case of Ag/TiO2 catalysts, the mean inner potential of Ag does not increase though the size of the Ag particle decreases to under 2nm.

Keywords

catalyticnanostructuretransmission electron microscopy (TEM)
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 900: Symposium O – Nanoparticles and Nanostructures in Sensors and Catalysis , 2005 , 0900-O09-31
Copyright
Copyright © Materials Research Society 2006

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

REFERENCES

1. Haruta, M., Catal. Today, 36 153–166 (1997).Google Scholar
2. Tauster, S. J., Acc. Chem. Res. 20 389 (1987).Google Scholar
3. Bowker, M., Stone, P., Bennett, R., and Perkins, N., Surface. Sci. 497 155–165, (2002).Google Scholar
4. Bowker, M., James, D., Stone, P., Bennet, R., Perkins, N., Millard, L., Greaves, J., and Dickinson, A., J. Catal. 217 427–433, (2003).Google Scholar
5. Li, Y., Fan, Y., Yang, H., Xu, B., Feng, L., Yang, M., and Chen, Y., Chem. Phys. Lett. 372 160–165, (2003).Google Scholar
6. Ichikawa, S., Okazaki, K., Akita, T., Okumura, M., Tanaka, K., and Kohyama, M., in Spaatially Resolved Characterization of Local Phenomena in Materials and Nanostructures, edited by Piqueras, J., Zypman, F. R., Bonnell, D. A. and Shreve, A. P., (Mater. Res. Soc. Proc. 738, Pittsburgh, PA, 2002) pp. 257–262.Google Scholar
7. Tada, H., Ishida, T., Takao, A., Ito, S., Mukhopadhyay, S., Akita, T., Tanaka, K., and Kobayashi, H., Chem. Phys. Chem. 6, 1537–1543, (2005).Google Scholar
8. Zhang, F., Jin, R., Chen, J., Shao, C., Gao, W., Li, L., and Guan, N., J Catal. 232, 424–431, (2005).Google Scholar
9. Smith, D. J., and McCartney, M. R., in Introduction to Electron Holography edited by Volkl, E., Allard, L. F. and Joy, D. C. (Kluwer Academic / Plenum Publishers, New York, 1999), pp. 87–124.Google Scholar
10. Spence, J. C. H., Acta Cryst. A49, 231–260, (1993).Google Scholar
11. Radi, G., Acta Cryst. A26, 41–56, (1970).Google Scholar
12. Buhl, R., Zeitschrift fur Phsik 155, 395–412, (1959).Google Scholar
13. Keller, M., Zeitschrift fur Phsik 164, 274–291, (1961).Google Scholar
14. Ichikawa, S., Akita, T., Okazaki, K., Okumura, M., Tanaka, K., Kohyama, M., Mat. Res. Soc. Symp. Proc. Vol.788 443-448, (2004).Google Scholar
15. Ichikawa, S., Akita, T., Okumura, M., Haruta, M., Tanaka, K., and Kohyama, M., J. Electron Microsc. 52 21–26 (2003).Google Scholar