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Topics in Catalysis

, Volume 58, Issue 12–13, pp 769–775 | Cite as

Active Sites for Light Driven Proton Reduction in Y2Ti2O7 and CsTaWO6 Pyrochlore Catalysts Detected by In Situ EPR

  • Dirk HollmannEmail author
  • Oliver Merka
  • Larissa Schwertmann
  • Roland MarschallEmail author
  • Michael WarkEmail author
  • Angelika BrücknerEmail author
Original Paper

Abstract

In situ EPR spectroscopy proved to be a versatile tool to identify active sites for photocatalytic hydrogen generation in modified Y2Ti2O7 and CsTaWO6 catalysts of pyrochlore structure, in which the metal cations are located in two different positions A and B. It was found that the B-sites exclusively occupied by titanium (Y2Ti2O7) and tantalum/tungsten (CsTaWO6) act as electron traps on the surface. From these sites, electron transfer to the co-catalysts proceeds. Thus, the B-sites are responsible for photocatalytic water reduction.

Graphical Abstract

Keywords

EPR Mechanism Electron transfer Pyrochlore Photocatalysis 

Notes

Acknowledgments

This work has been supported by the German Science Foundation (DFG, WA 1116) and the Evonik Degussa GmbH (part-financed by the State of North Rhine-Westphalia and co-financed by the European Union Investing in our Future, European Regional Development Fund).

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Leibniz-Institute for Catalysis e.V. at the University of RostockRostockGermany
  2. 2.Institute for ChemistryCarl-von-Ossietzky-University OldenburgOldenburgGermany
  3. 3.Laboratory for Industrial ChemistryRuhr-University BochumBochumGermany
  4. 4.Institute of Physical ChemistryJustus-Liebig-University GiessenGiessenGermany

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