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Can one tailor a catalyst with particular properties?

Malgorzata Witko 

Polish Academy of Sciences, Institute of Catalysis and Surface Chemistry, Niezapominajek 8, Kraków 30-239, Poland

Abstract

A main goal of catalytic science is to tailor the most active and selective catalyst for a particular reaction. Such a goal demands synergy between two parallel and complementary approaches: experimental and theoretical, and gives the opportunity to manufacture catalyst for a particular reaction. In the following the role of theory will be will be illustrated on the example of V-O systems.

Vanadia-based catalysts are used in many different processes that belong to various types of chemical reactions. Their wide application follows from a fact that V2O5 crystallites may exhibit two structurally different types of faces: surface built of chemically saturated atoms and those built of unsaturated cations and anions. Both show different behavior in catalytic reactions by performing a complex multi-step operation on the reacting molecule through activation of some of the bonds within reactant and hindering those interactions, which could result in unwanted product.

In the lecture the energetic stability of low-indices (010), (100) and (001)V2O5 surfaces will be compared based upon periodic DFT calculations. The electronic structure and activity of structurally different surface O sites will be discussed using both cluster and periodic approaches. Adsorption of H leading to the formation of surface OH and H2O species as well as hydrogen migration through the surfaces will be considered. Creation of surface oxygen vacancies will be undertaken and followed by their re-oxidation through the gaseous oxygen.

 

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Presentation: Keynote lecture at E-MRS Fall Meeting 2006, Symposium B, by Malgorzata Witko
See On-line Journal of E-MRS Fall Meeting 2006

Submitted: 2006-05-11 08:39
Revised:   2009-06-07 00:44