TY - JOUR AU - NilssonPingel, Torben AU - Fouladvand, Sheedeh AU - Heggen, Marc AU - Dunin-Borkowski, Rafal AU - Jäger, Wolfgang AU - Westenberger, Peter AU - Phifer, Daniel AU - McNeil, Jace AU - Skoglundh, Magnus AU - Grönbeck, Henrik AU - Olsson, Eva TI - 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/Al 2 O 3 Catalyst JO - ChemCatChem VL - 9 IS - 18 SN - 1867-3880 CY - Weinheim PB - WILEY-VCH Verlag M1 - FZJ-2018-00780 SP - 3544 - 3553 PY - 2017 AB - 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 by using several high-resolution electron microscopy techniques such as STEM, FIB/SEM slice & view, SEM and EDX. A combination of these analytic techniques and advanced TEM specimen preparation allowed for three-dimensional probing at different length scales, avoiding the random character of conventionally crushed powder specimens owing to site specificity. A core–shell distribution of Pt–Pd nanoparticles within the alumina support particles, with enlarged nanoparticles (≈1.5 to 40 nm) 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. LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000411499300014 DO - DOI:10.1002/cctc.201700479 UR - https://juser.fz-juelich.de/record/842561 ER -