title: Determining the location and nearest neighbours of aluminium in zeolites with atom probe tomography.
abstract: Zeolite catalysis is determined by a combination of pore architecture and Brønsted acidity. As Brønsted acid sites are formed by the substitution of AlO4 for SiO4 tetrahedra, it is of utmost importance to have information on the number as well as the location and neighbouring sites of framework aluminium. Unfortunately, such detailed information has not yet been obtained, mainly due to the lack of suitable characterization methods. Here we report, using the powerful atomic-scale analysis technique known as atom probe tomography, the quantitative spatial distribution of individual aluminium atoms, including their three-dimensional extent of segregation. Using a nearest-neighbour statistical analysis, we precisely determine the short-range distribution of aluminium over the different T-sites and determine the most probable Al-Al neighbouring distance within parent and steamed ZSM-5 crystals, as well as assess the long-range redistribution of aluminium upon zeolite steaming.
authors.affiliation: Pacific Northwest National Laboratory, Environmental Molecular Science Laboratory, 3335 Innovation Boulevard, Richland, Washington 99352, USA.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Perea
authors.affiliation: Pacific Northwest National Laboratory, Institute for Integrated Catalysis, 902 Battelle Boulevard, Richland, Washington 99352, USA.
authors.forename: Ilke
authors.initials: I
authors.lastname: Arslan
authors.affiliation: Pacific Northwest National Laboratory, Environmental Molecular Science Laboratory, 3335 Innovation Boulevard, Richland, Washington 99352, USA.
authors.forename: Jia
authors.initials: J
authors.lastname: Liu
authors.affiliation: Faculty of Science, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, Utrecht 3584 CG, The Netherlands.
authors.forename: Zoran
authors.initials: Z
authors.lastname: Ristanović
authors.affiliation: Pacific Northwest National Laboratory, Environmental Molecular Science Laboratory, 3335 Innovation Boulevard, Richland, Washington 99352, USA.
authors.forename: Libor
authors.initials: L
authors.lastname: Kovarik
authors.affiliation: Pacific Northwest National Laboratory, Environmental Molecular Science Laboratory, 3335 Innovation Boulevard, Richland, Washington 99352, USA.
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Arey
authors.affiliation: Pacific Northwest National Laboratory, Institute for Integrated Catalysis, 902 Battelle Boulevard, Richland, Washington 99352, USA.|Department of Chemistry, TU Munich, Lichtenbergstrasse 4, Garching 85748, Germany.
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Lercher
authors.affiliation: UOP LLC, a Honeywell Company, 25 E. Algonquin Road Des Plaines, Illinois 60016, USA.
authors.forename: Simon R
authors.initials: SR
authors.lastname: Bare
authors.affiliation: Faculty of Science, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, Utrecht 3584 CG, The Netherlands.
authors.forename: Bert M
authors.initials: BM
authors.lastname: Weckhuysen