[en] The structure formation of cogelled Pd/SiO2 catalysts is followed in situ at the nanometer scale using timeresolved small-angle X-ray scattering (SAXS). The SAXS patterns are analyzed in terms of a reaction-induced spinodal decomposition that is responsible for the formation of the silica support and most likely for the metal dispersion as well. The results are discussed in the light of recent electron tomography characterizations of the catalysts. The latter technique reveals regularity in the metal dispersion, the origin of which is likely to be the very occurrence of a spinodal phase separation.
Disciplines :
Physical, chemical, mathematical & earth Sciences: Multidisciplinary, general & others
Author, co-author :
Gommes, Cédric ; Université de Liège - ULiège > Département de chimie appliquée > Chimie physique appliquée
Goderis, Bart; Katholieke Universiteit Leuven - KUL
Pirard, Jean-Paul ; Université de Liège - ULiège > Département de chimie appliquée > Chimie physique appliquée
Language :
English
Title :
Relevance of Spinodal Decomposition for Support Formation and Metal Dispersion in Cogelled Pd/SiO2 Catalysts
Publication date :
07 July 2007
Journal title :
Journal of Physical Chemistry. C, Nanomaterials and interfaces
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