Laboratory for Materials Characterisation
The “Materials Characterisation Lab” provides a large range of analytical facilities for investigation of crystallographic properties such as crystal phase identity, bond lengths and angles as well as site occupancies of lattice sites. Band structure, defect formation in grain and grain boundaries as well as associated transport properties are studied by a means of a portfolio of electrochemical ac and dc methods. A recent addition are experimental setups to determine gas permeation rates (hydrogen and oxygen) in materials.
Bruker D8 Advance x-ray diffractometer: Cu Kα X-ray source, X-ray patterns in Bragg-Brentano or grazing incidence for 2θ angles between 5° and 140° with a resolution of 0.02°can be obtained by means of a LYNXEYE point and linear detector. X-ray diffraction (XRD) on polycrystalline layers and powders for identification of crystal phases and crystal size determination. Analysis is performed by Diffrac Eva software and Rietveld refinement by TOPAS software using multiple licensed databases.
Malvern Instruments MasterSizer 2000: Determination of particle size distributions for powders ranging from 20 nm to 2 mm particle size. Additional options are calculation of the specific surface and averaged particle size. Particle size distribution can be displayed as a function of particle volume, surface area or statistic particle number. Powders can be dispersed either in dry or in wet environment.
Renishaw inVia Raman microscope: Raman spectroscopy by means of a RL532C100 Laser source (wavelength = 532 nm, Pmax>1W) for the characterization of materials using molecular vibrations or phonon vibrations in solids. Wavenumbers ranging from 100 cm-1 to 3600 cm-1 can be analyzed using the WiRE Windows-based Raman Environment) software.
Digital microscope Keyence: 2D and 3D photos of up to 1000x magnification
FTIR-Spectrometer: Bruker VERTEX 70v: digital FTIR vacuum spectrometer for measurements in the MIR range (8000 to 350 cm-1) and FIR range (600 to 50 cm-1) with grazing reflection unit, ATR unit for both spectral ranges, and variable reflection unit
Buehler cross-section preparation kits: Mechanical polishing device Buehler EcoMet250 und precision saw IsoMet 4000 are employed to realize cross-sections of to a 50nm finish.
Zahner TLS03 and Autolab PGSTAT 302N including impedance Jig For AC impedance spectroscopy for frequencies ranging from 0.1 Hz to 10 MHz with possible use of a DC bias for the separation of bulk and grain boundary conductivities in different atmospheres and temperature regimes. Moreover, cyclic voltammetry can be used to study materials in solution.
Hydrogen perimeability test jig: Measurements of the permeability of hydrogen in materials by means of mass spectroscopy.
Furthermore, A setup for ammonia synthesis by electrolysis and an oxygen permeability jig are under construction.
