Three-dimensional probing of catalyst ageing on different length scales: A case study of changes in microstructure and activity for CO oxidation of a Pt-Pd/Al2O3 catalyst
Artikel i vetenskaplig tidskrift, 2017
In the present study the effects of thermal treatment on the microstructure of a Pt-Pd/Al2O3 oxidation catalyst and its activity for CO oxidation have been studied. The microstructural analysis was performed using several high-resolution electron microscopy techniques like STEM, FIB/SEM slice & view, SEM and EDX. A combination of these analysis techniques and advanced TEM specimen preparation allowed for three-dimensional probing at different length scales avoiding the random character of conventionally crushed powder specimens due to site specificity. A core-shell distribution of Pt-Pd nanoparticles within the alumina support particles, with enlarged nanoparticles (≈ 1.5 to 40 nm) being present in the shell and small nanoparticles (< 1.5 nm) in the core, was revealed in the untreated catalyst. A more uniform spatial
distribution developed during thermal treatment at 700 °C or higher with larger nanoparticles forming in the core. Accompanying measurements of the catalytic activity for CO oxidation showed the detrimental effect of sintering of the small nanoparticles on the
reaction rate and apparent activation energy of the reaction.
platinum
CO oxidation
TEM
SEM
palladium
Författare
Torben Pingel
Chalmers, Fysik, Eva Olsson Group
Kompetenscentrum katalys
Sheedeh Fouladvand
Chalmers, Kemi och kemiteknik, Tillämpad kemi
Kompetenscentrum katalys
Marc Heggen
Forschungszentrum Jülich
R. E. Dunin-Borkowski
Forschungszentrum Jülich
Wolfgang Jäger
Kompetenscentrum katalys
Chalmers, Fysik
Peter Westenberger
FEI Company
Daniel Phifer
FEI Company
Jace McNeil
FEI Company
Magnus Skoglundh
Chalmers, Kemi och kemiteknik, Tillämpad kemi
Kompetenscentrum katalys
Henrik Grönbeck
Kompetenscentrum katalys
Chalmers, Fysik, Kemisk fysik
Eva Olsson
Chalmers, Fysik, Eva Olsson Group
Kompetenscentrum katalys
ChemCatChem
1867-3880 (ISSN) 1867-3899 (eISSN)
Vol. 9 18 3544-3553Enabling Science and Technology through European Electron Microscopy (ESTEEM 2)
Europeiska kommissionen (EU) (EC/FP7/312483), 2012-10-01 -- 2016-09-30.
Drivkrafter
Hållbar utveckling
Styrkeområden
Nanovetenskap och nanoteknik
Transport
Energi
Materialvetenskap
Ämneskategorier
Kemiska processer
Den kondenserade materiens fysik
DOI
10.1002/cctc.201700479