Solid Liquid Analysis System /PM3

The Surface Science Laboratory at Technical University of Darmstadt operates a dedicated UHV system for photoemission spectroscopy (PES) experiments with synchrotron radiation as excitation at the Berlin synchrotron facility (BESSY II). The so called SOLIAS system (solid liquid analysis system - Figure 1) is especially designed for the investigation of the solid-liquid interface and offers the possibility to deposit volatile materials on surfaces of interest and freeze them (LN2) to perform photoemission spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) or low energy electron diffraction (LEED) analysis. A dedicated electrochemical cell connected via a buffer chamber allows for electrochemical treatment of samples under an inert atmosphere (Figure 2).

At the PM3 dipole beamline the energy range of 20 – 2000 eV with high photon flux, high energy resolution and high stability and circular polarization is available.

Selected Applications:

• Investigation of solids (amorphous, crystalline), especially semiconductor and metals
• Studying the interface and surface reactions after wet-chemical treatment in valence and core level regions
• Varying the information depth by tuning the excitation energy
• Measurement of the electronic properties of the surface (e.g. band line-up, valence band maximum, work function)
• Electrochemistry in combination with PES, NEXAFS and LEED

Figure 1. SOLIAS

Methods

NEXAFS, LEED, XPS

Remote access

not possible

Figure 2. Electrochemistry cell.

Figure 3. SOLIAS endstation layout

To keep a high degree of flexibility, it is mounted on a moveable frame to allow the attachment to various beamlines (Figure 3).

At the moment the SOLIAS system is mainly used for fundamental research on Li-batteries, electrocatalysts, semiconductors for water splitting and absorber materials for thin film photovoltaics.