Refining nature: field-modified surface processes
Juri Suchorski
Institut für Materialchemie, Technische Universität Wien
17:00 - 18:00 Tuesday 18 May 2010 KFU HS 05.01 Externally applied high electrostatic field in order of Volt per Ångström is comparable with the internal electrostatic field inside the molecules, adsorption bonds and solid-gas interfaces. Correspondingly, it is high enough to rearrange the electrons near the surface and modify thus the adsorption bonds or induce significant changes in the electron density distribution modifying in this way the electronic properties of the surface [1]. Even the chemical bonds within the molecules exposed to such field may be modified. This leads to such effects as field-induced chemisorption of noble gases, field-desorption or even field evaporation of metals [2], etc.
In present contribution, measurements of high electrostatic field above individual surface atoms using the field ion appearance energy spectroscopy (FIAES) will be presented and three examples of the high field effect at metal surfaces will be discussed: field-enhanced adsorption of CO on Pt [3], field-modified CO oxidation reaction on Pt [4] and field-induced surface oxidation of Rh [5].
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Progr.Surf.Sci. 48, 121 (1994).
[2] Y. Suchorski, N. Ernst, W.A. Schmidt, V. Medvedev, H.J. Kreuzer, R.L.C. Wang
Progr.Surf.Sci. 53, 135 (1996)
[3] Y. Suchorski, W. Drachsel, G. Rupprechter, Ultramicr. 109, 430 (2009)
[4] Y. Suchorski, W. Drachsel, Top. Catal. 46, 201 (2007).
[5] V. K. Medvedev, Y. Suchorski, C. Voss, T. Visart de Bocarme, T. Bär
and N. Kruse, Langmuir 14, 6151 (1998).
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