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The mobility of an alkali promoter as probed in situ during a catalytic reaction: Li in the CO oxidation on Pt
Author(s) -
Suchorski Y.,
Beben J.,
Frac A.,
Medvedev V. K.,
Weiss H.
Publication year - 2007
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/sia.2482
Subject(s) - catalysis , chemistry , lithium (medication) , ion , diffusion , desorption , in situ , alkali metal , anisotropy , field desorption , analytical chemistry (journal) , field emission microscopy , field ion microscope , common emitter , surface diffusion , nanometre , adsorption , materials science , diffraction , ionization , optics , optoelectronics , physics , thermodynamics , medicine , biochemistry , organic chemistry , chromatography , composite material , endocrinology
Fluctuations of the local ion rate of Li + ions emitted during in situ monitoring of the catalytic CO oxidation on the nanofacets of a Pt field emitter tip with a lithium field desorption‐microscope (Li‐FDM) are utilized to study the Li surface diffusion. The ‘virtual probe‐hole’ approach, which is based on the digitization of the Li‐FDM video images, is used. This allows to analyze simultaneously the local fluctuations of ions originating from arbitrarily user‐defined probed surface regions of nanometer size. The anisotropy of the Li diffusion on the spatially inhomogeneous Pt surface is directly proved and a slowing effect of the coadsorbed CO on the Li diffusion is observed. Copyright © 2007 John Wiley & Sons, Ltd.