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In Situ Ptychography of Heterogeneous Catalysts using Hard X-Rays: High Resolution Imaging at Ambient Pressure and Elevated Temperature

Published online by Cambridge University Press:  25 February 2016

Sina Baier
Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
Christian D. Damsgaard
Center for Electron Nanoscopy, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark Center for Individual Nanoparticle Functionality, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
Maria Scholz
Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
Federico Benzi
Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
Amélie Rochet
Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
Robert Hoppe
Institute of Structural Physics, Technische Universität Dresden, 01062 Dresden, Germany
Torsten Scherer
Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
Junjie Shi
Angewandte und Physikalische Chemie, University of Bremen, 28359 Bremen, Germany
Arne Wittstock
Angewandte und Physikalische Chemie, University of Bremen, 28359 Bremen, Germany
Britta Weinhausen
European Synchrotron Radiation Facility, 38043 Grenoble, France
Jakob B. Wagner
Center for Electron Nanoscopy, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
Christian G. Schroer
Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany Department Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
Jan-Dierk Grunwaldt*
Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
*Corresponding author.
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A new closed cell is presented for in situ X-ray ptychography which allows studies under gas flow and at elevated temperature. In order to gain complementary information by transmission and scanning electron microscopy, the cell makes use of a Protochips E-chipTM which contains a small, thin electron transparent window and allows heating. Two gold-based systems, 50 nm gold particles and nanoporous gold as a relevant catalyst sample, were used for studying the feasibility of the cell. Measurements showing a resolution around 40 nm have been achieved under a flow of synthetic air and during heating up to temperatures of 933 K. An elevated temperature exhibited little influence on image quality and resolution. With this study, the potential of in situ hard X-ray ptychography for investigating annealing processes of real catalyst samples is demonstrated. Furthermore, the possibility to use the same sample holder for ex situ electron microscopy before and after the in situ study underlines the unique possibilities available with this combination of electron microscopy and X-ray microscopy on the same sample.

Materials Applications
© Microscopy Society of America 2016 

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