The ´in situ spectroscopy/synchrotron methods´ team which is located both at IKFT and the Institute for Chemical Technology and Polymerchemistry (ITCP) applies synchrotron based X-ray absorption spectroscopy and complementary techniques to analyze structural properties of catalysts and their catalytic performance. Structure-activity relationships obtained in this way play a key role in the development and optimization of catalytically active materials. Important application areas are fine chemistry, materials for renewable energy technologies, biomass conversion and other topics at the Institute of Catalysis Research and Technology.
Many catalysts are very sensitive to reaction conditions. Dynamic structural changes occur within subsecond time intervals (e. g. milliseconds during the ignition of a reaction), minutes, hours (e. g. activation) or days (deactivation). To analyze this dynamic behavior, catalysts and catalytic processes are investigated under reaction conditions also denoted “in situ” or “operando”. A number of sample cells have been specially designed e. g. for high temperature, high pressure, gas and liquid phase reactions.
The in situ experiments are equipped with a gas dosing system that allows variations of the gas mixture and a mass spectrometer and FTIR system for on-line gas analysis of reaction products. Combined set-ups for complementary techniques simultaneously provide information about the crystalline and X-ray amorphous structure and surface species. Special focus is further laid on time resolved and spatially resolved studies using microscopic and tomographic techniques.
Group members frequently perform X-ray absorption spectroscopic and X-ray microscopic experiments at KIT Synchotron (XAS beamline), PETRA III (DESY), SLS, SOLEIL, ESRF and other synchrotron radiation sources. A new beamline dedicated to actinide and catalysis research is currently being built up at KIT in close collaboration with ANKA scientists and the Institute for Nuclear Waste Disposal (INE) along with a special infrastructure for catalysis research at KIT Synchrotron.
In situ characterization under reaction conditions:
- Infrared spectroscopy
- Raman spectroscopy
- UV-vis spectroscopy
- X-ray diffraction
- synchrotron based techniques:
- x-ray absorption spectroscopy (XANES, EXAFS)
- x-ray emission spectroscopy (XES)
- resonant inelastic x-ray scattering (RIXS)
- X-ray microscopy
- CAT-ACT beamline (dedicated to Catalysis and Actinide research) at ANKA, designed for photon energies up to 60 keV