BElChem-PGM station

BElChem-PGM station

The scientific aim at the BElChem-PGM station is to study the electronic surface/near surface structure of functional materials in the presence of a reactive environment. This includes both gas/solid interfaces (e.g. heterogeneous catalysis) and liquid/solid interfaces (e.g. catalytic water splitting).

Selected Applications:
  • X-ray photoelectron spectroscopy (XPS) under high vacuum (p=10^(-8) mbar) and near ambient pressure conditions (maximum 20mbar, typically 1 mbar)
  • X-ray aborption spectroscopy (XAS) at pressure up to 20 mbar with NAP-HE-XPS endstation
  • log-in methodology applying the beamline chopper to modulate the incoming X-ray induced signal

Methods

Time-resolved absorption, NEXAFS, EXAFS, Mass Spectrometry, XPS

Remote access

depends on experiment - please discuss with Instrument Scientist

Beamline data
Energy range 90 - 2000 eV
Energy resolution 70meV at 400eV photon energy
Flux 4.00 1013 mbar photons/s@300mA
Polarisation horizontal
Focus size (hor. x vert.) 100 µm X 20 µm (expected)
Phone +49 30 8062 14842
More details BElChem-PGM
Station data
AP-XPS
Temperature range room temperature up to 1000 K
Pressure range Maximum pressure: 20 mbar
Minimum pressure: 10-8 mbar
Typical pressure: 1 mbar

For more details contact the instrument scientist.
Detector 1D delay line detector (1D DLD) (SURFACE CONCEPT, Mainz)
Manipulators various, exchangeable for optimised sample environments
Sample holder compatibility Homemade concept. For details contact the instrument scientist.
Additional equipment PRISMA 200 mass spectrometer, FISHER SCIENTIFIC gas chromatograph, process gas pumping line, electrolyte dosing module with perestaltic pump

Obviously, the understanding of the interaction of a catalyst surface with the reactants plays a key role in a detailed description of catalytic processes. X-ray photoelectron spectroscopy (XPS) is a well-established powerful tool to study in detail the outermost surface of solids but it was traditionally restricted to high vacuum and low pressure conditions. However, recently a methodology based on a differentially pumped electrostatic lens system has gained much interest and opened possibility to study catalytic processes in more diverse environments.

The Berlin Joint Lab for Electrochemical Interfaces (BElChem) is located at the BESSY II synchrotron in Berlin, Germany, and co-run by the Fritz-Haber-Institut, the Max-Planck-Institut of Chemical Energy Conversion and the Helmholtz-Zentrum Berlin. BElChem focuses on providing a molecular-level description of (photo)electrochemical interfaces that are of high relevance for solar fuel production and renewable energy storage.

The BElChem facility consists of two beamlines with two endstations in two separate hutches and an additional sample preparation/chemical lab. BElChem-PGM (plane grating monochromator) covers the soft X-ray energy range, whereas BElChem-DCM (a dipole magnet sourced beamline) with a double crystal monochromator (DCM) covers the tender X-ray energy range.

Please find more details on BElChem in 

David E. Starr, Michael Hävecker, Axel Knop-Gericke, Marco Favaro, Simone Vadilonga, Marcel Mertin, Gerd Reichardt, Jan-Simon Schmidt, Frank Siewert, Robert Schulz, Jens Viefhaus, Christian Jung & Roel van de Krol (2022) The Berlin Joint Lab for Electrochemical Interfaces, BElChem: A Facility for In-situ and Operando NAP-XPS and NAP-HAXPES Studies of Electrochemical Interfaces at BESSY II, Synchrotron Radiation News, 35:3, 54-60, DOI: 10.1080/08940886.2022.2082209