ISSN:
1572-9028
Keywords:
laser interference lithography
;
model catalyst
;
palladium
;
silver
;
copper
;
metal evaporation
;
spin‐coating
;
SEM
;
AFM
;
XPS
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Nanostructured 4 inch Si wafers were prepared as new supports for model catalysts. A single wafer exhibits 109–1010 pits on an otherwise flat silicon oxide surface. To produce these nanostructures, oxidized wafers were covered with photoresist material and exposed to laser interference patterns. Using hydrofluoric acid, wet‐chemical etching of the SiO2 through the structured resist resulted in a pitted surface. The etched pits with diameters of 200–400 nm and depths between 50 and 70 nm were loaded with metal particles by evaporation (palladium, silver) or by means of spin‐coating (copper). Optimizing the methods enabled exact deposition of single metal clusters in the pits. The resulting model catalysts are remarkably stable against sintering, a major problem of conventional model catalysts when exposed to elevated temperatures and oxidizing gas atmosphere. The topography and chemical composition as well as their changes, induced by the reaction conditions applied, including stability and chemical behavior of the nanostructured systems, were investigated by means of AFM, SEM, temperature‐programmed methods and XPS. To determine their usefulness in catalysis, specially designed reactors were developed for catalytic investigations.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009091901986
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