Il Nuovo Cimento D

, Volume 19, Issue 11, pp 1641–1648 | Cite as

In situ characterization of highly dispersed catalysts included within zeolite cavities and their photocatalytic reactivities

Article
Received:
Accepted:

Summary

A detailed characterization of catalysts prepared within zeolite cavities and their photocatalytic reactivities have been investigated usingin situ photo-luminescence, diffuse reflectance absorption, XAFS (XANES and FT-EXAFS) and ESR techniques. With the Ag+/ZSM-5 catalyst, it was found that Ag+ ions are highly dispersed in an isolated state within the zeolite cavities. UV irradiation of the Ag+/ZSM-5 catalyst in the presence of NO leads to the decomposition of NO into N2, O2 and N2O at 275 K. Dynamic studies show that the electron transfer from the excited state of the Ag+ ions (4d95s1) plays a significant role in initiating the decomposition of NO. Titanium oxide catalysts prepared within the Y-zeolite cavities via an ion-exchange method exhibit high and unique photocatalytic reactivities for the decomposition of NO into N2 and O2 as well as the reduction of CO2 with H2O showing a high selectivity for the formation of CH3OH. It was also found that the charge transfer excited state of the titanium oxide species, (T3+ -O-)*, plays a vital role in these unique photocatalytic reactions.

PACS 82.65.Jv

Heterogeneous catalysis at surfaces 

PACS 01.30.Cc

Conference proceedings 
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    Anpo M., andYamashita H., inSurface Photochemistry, edited by M. Anpo (John Wiley & Sons, London) 1996.Google Scholar
  2. [2]
    Anpo M., Matsuoka M. andYamashita H.et al., J. Phys. Chem.,98 (1994) 5744.CrossRefGoogle Scholar
  3. [3]
    Matsuoka M., Yamashita H. andAnpo M.et al.,Chem. Lett. (1995) 375.Google Scholar
  4. [4]
    Anpo M.,Solar Energy Materials and Solar Cells,38 (1995) 221.CrossRefGoogle Scholar
  5. [5]
    Yamashita H., Matsuoka M. andAnpo M.et al., J. Phys. Chem.,100 (1996) 397.CrossRefGoogle Scholar
  6. [6]
    Matsuoka M., Yamashita H. andAnpo M.,et al.,J. Mol. Catal.,107 (1996) 399.CrossRefGoogle Scholar
  7. [7]
    Yamashita H., Ichihashi Y. andAnpo M.et al., J. Phys. Chem.,100 (1996) 16041.CrossRefGoogle Scholar
  8. [8]
    Anpo M., Zhang S. G. andYamashita H.,11th Int. Congr. Catal.,101 (1996) 941.Google Scholar
  9. [9]
    Zhang S. G., Ichihashi Y., Yamashita H. andAnpo M.,et al.,Chem. Lett. (1996) 895.Google Scholar
  10. [10]
    Yamashita H., Ichihashi Y. andAnpo M.,J. Phys. Chem.,101 (1997) 2632.Google Scholar
  11. [11]
    Anpo M., to be published inJpn. Catal. Surv.,1 (1997).Google Scholar

Copyright information

© Società Italiana di Fisica 1997

Authors and Affiliations

  1. 1.Department of Applied ChemistryOsaka Prefecture University — SakaiOsaka 599Japan

Personalised recommendations