Equipment and methods
CAT Beamline
The CAT end station of the CAT-ACT beamline at ANKA is dedicated to catalytic research using X-ray spectroscopic techniques. It will be operated by the Grunwaldt group at the Institute for Chemical Technology and Polymer Chemistry and the Institute of Catalysis Research and Technology .
Synchrotron radiation based techniques have evolved as key speciation methods in catalysis research, especially with respect to in-situ and in-operando X-ray based characterization techniques as a basis for a rational design of heterogeneous catalysts. Knowledge of oxidation state and coordination environment of the catalytically active centers, nanoparticle morphology etc. contributed significantly to a deeper understanding of heterogeneously catalyzed reactions and serves today as a basis for the design of new catalysts and for first-principles kinetic modeling. The beamline design places emphasis on in situ X-ray Absorption Spectroscopy (XAS) in terms of X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure spectroscopy (EXAFS) in a photon energy range from 5 keV up to 60 keV. These techniques are combined with X-Ray Diffraction (XRD), Infrared Spectroscopy and other correlative spectroscopic methods. Special infrastructure for catalytic studies under reaction conditions in gas phase, liquid phase and at elevated pressure has been or is currently being built up.
Key references:
- J.-D. Grunwaldt, M. Caravati, S. Hannemann, A.Baiker, „In situ X-ray Absorption Spectroscopy under Reaction Conditions: Suitability of Different Reaction Cells for Combined Catalyst Characterization and Time-resolved Studies“, Phys. Chem. Chem. Phys. 6, 3037 (2004).
- J.-D. Grunwaldt, A. Baiker, “In situ Spectroscopic Investigation of Heterogeneous Catalysts and Reaction Media at High Pressure”, Phys. Chem. Chem. Phys. 7, 3526 (2005).
- S. Hannemann, M. Casapu, J.-D. Grunwaldt, P. Haider, P. Trüssel, A. Baiker, and E. Welter, “A versatile in situ spectroscopic cell fluorescence/transmission EXAFS and X-ray diffraction of heterogeneous catalysts in gas and liquid phase”, J. Synchrotron Radiat. 14, 345 (2007).
- J.-D. Grunwaldt, In situ Analysis of Heterogeneous Catalysts in Chemical Energy Conversion, in: R. Schlögl (Ed.) Chemical Energy Storage, Walter de Gruyter GmbH, Berlin/Boston, ISBN: 978-3-11-026632-0, 2012, pp. 311.
- A. Zimina, K .Dardenne, M. A. Denecke, J.- D. Grunwaldt, E. Huttel, H. Lichtenberg, S. Mangold, T. Pruessmann, J. Rothe, R. Steininger, T.Vitova, “ The CAT-ACT Beamline at ANKA: A new high energy X-ray spectroscopy facility for CATalysis and ACTinide research“, J. Phys. Conf. Ser., accepted for publication (2015)