Gerätepark/Analytik

Raman Spectrometer (MonoVista CSRF S & I)

Non-destructive identification of phases, defects and lattice strain in solids via their characteristic scattering signatures of infrared light.

Our modular Raman spectroscopy system consists of a laser, a confocal probe and a spatially resolving measurement unit, enabling non-destruc-tive investigations of solid and liquid samples. Raman spectroscopy is highly sensitive to lattice distortions, phase mixtures and local defects in crystal structures. In our group, we use Raman spectroscopy for example to analyse phase purity and detect structural changes in ceramic materials.

Infrared Spectrometer (Prestige 21, Shimadzu)

Fast, non-destructive identification of chemical bonds and functional groups – for solids, liquids and gases.

We use a Fourier-transform infrared spectrometer for the rapid identifi-cation of chemical bonds and functional groups in solids, liquids and gases. FTIR is one of the most versatile methods in chemical analysis – from phase identification to trace analytics. In our group, we use it to charac-terise synthesised ceramics after calcination (detection of residual carbo-nates, OH groups, lattice distortions caused by doping, etc.) or to inves-tigate adsorbed species on catalyst surfaces in order to elucidate reaction mechanisms.

UV-Vis Spectrometer (UV-2600, Shimadzu)

UV-Vis absorption under reaction conditions – band gaps, oxidation states and catalytic processes tracked in real time.

The Shimadzu UV-2600 UV-Vis spectrophotometer is equipped with a Harrick temperature cell and flow control for in-situ and operando measurements, allowing samples to be monitored spectroscopically directly under reaction conditions (controlled temperature and gas atmosphere). In our group, we use it to determine optical band gaps (Tauc plot), the oxidation state of dopants in ceramics and to track in-situ catalytically relevant colour changes of materials – e.g. reduction and re-oxidation under reaction conditions.

Fluorescence Spectrometer (RF-6000, Shimadzu)

Highly sensitive measurement of excitation and emission spectra in the UV-Vis range – for the optical and electronic characterisation of materials.

The high-sensitivity fluorescence spectrophotometer is suitable for exci-tation and emission measurements in the UV-Vis range on solutions and solids. In addition to classical fluorescence spectra, it enables time-resolved measurements and the determination of quantum yields. In our group, we use the instrument to investigate optical properties and defect levels in ceramics – for instance, how dopants influence luminescence and charge-transfer processes.

NMR Spectrometer (500 MHz, JEOL, shared instrument)

High-resolution structure elucidation via the magnetic properties of atomic nuclei – with 500 MHz performance even for demanding solid-state samples.

The high-field NMR spectrometer with superconducting cryomagnet provides high-resolution nuclear magnetic resonance spectroscopy for liquid and solid-state samples. The high field strength enables the resolution of closely spaced signals and the investigation of low-sensitivity nuclei. In our group, we use NMR for example for the structural characterisation of precursor compounds (e.g. metal salt complexes, sol-gel precursors) and can employ ¹⁰⁷Ag and ¹⁰⁹Ag NMR and related techniques for structural insights into ceramic phases after synthesis. This instrument is shared with the entire Chemistry Department.

Gas Physisorption (BET, QUADRASORB, Quantachrome)

Simultaneous determination of specific surface area, pore volume and pore size distribution on up to four samples in a single run.

The Quantachrome QUADRASORB is a fully automated 4-channel physisorption instrument for the simultaneous determination of specific surface area (BET method), pore size distribution and pore volume. Parallel measure-ment of four samples makes it an efficient high-throughput tool in catalyst development. In our group, we use it to systematically compare different synthesis routes and calcination temperatures for ceramic catalysts – since high specific surface area and suitable pore structure are crucial for catalytic performance.

Degassing Station (BELPREP VAC II, Microtrac)

Degas up to six samples simultaneously under vacuum and heat – the indispensable preparation step for precise BET measurements.

The Microtrac MRB BELPREP VAC II is a 6-channel vacuum degassing unit for sample preparation prior to BET surface area measurements. Before every physisorption measurement, adsorbed gases and moisture must be completely removed from the sample surface – otherwise they distort the result. In our group, we use it to pre-pare (calcined) ceramic powders for precise BET measurements in order to quantitatively assess the influence of synthesis route and doping on the specific surface area.

Chemisorption (BELCAT II, Microtrac)

Fully automated characterisation of catalyst surfaces via temperature-programmed reduction, oxidation and desorption (TPR/TPO/TPD).

We use a fully automated chemisorption analyser for temperature-programmed techniques (TPR, TPO, TPD). It enables the characterisation of the surface chemistry of catalysts: how readily can active sites be reduced or re-oxidised, and how strongly do gases bind to the surface? In our group, we use the BELCAT II to systematically investigate the redox properties of our catalysts – a decisive parameter for understanding catalytic activity and selectivity.

High-Temperature Thermoanalysis – DTA/TGA (PT 1600, Linseis)

Simultaneous recording of heat flow and mass change under defined atmosphere – with forced-flow operation for precise calorimetric measurements up to high temperatures.

The thermoanalysis system PT 1600 (Linseis) combines differential thermal analysis (DTA) and thermogravimetry (TGA) in a single instrument. The DTA records exo- and endothermic processes such as phase transitions or decomposition reactions as a heat flow signal, while the TGA simultaneously quantifies the associated mass changes. Forced-flow operation ensures a defined, continuous gas flow through the sample chamber, guaranteeing reproducible atmosphere conditions and a reliable baseline. In our group, we use the system to determine phase transition temperatures in ceramics, to trace the decomposition pathways of precursor compounds and to quantify oxygen vacancies under controlled redox atmospheres. The instrument can be coupled with our gas chromatograph to identify and quantify released gases not only mass-spectrometrically (TG-MS) but also chromatographically – providing an even more complete characterisation of thermally induced reactions.

Gas Chromatograph (8890, Agilent with Teckso Detector)

Quantitative separation and identification of gas mixtures – product gas analysis.

Our gas chromatograph (GC) enables the quantitative separation and analysis of gas mixtures with high sensitivity and reproducibility. It reliably separates even similar molecules such as H₂, CO, CO₂ and CH₄ from one another. Our GC can be directly coupled with the DTA/TGA system to chromatographically identify and quantify thermally released gases: a complement to mass-spectrometric analysis (TG-MS) that is particularly valuable for distinguishing between similar molecules.

Thermogravimetry with Gas Analysis – TG-MS (OmniStar GSD 350, Pfeiffer Vacuum)

Simultaneous measurement of mass changes and identification of released gases – every mass loss directly assigned to a reaction.

The thermogravimetry system (Pfeiffer Vacuum) is coupled via a heated capillary to a mass spectrometer, enabling the simultaneous measurement of mass changes and the identification of released gases. This allows every mass loss to be unambiguously assigned to a chemical process. In our group, we use it to track the thermal decomposition pathway of ceramic precursors (carbonate, nitrate, hydroxide precursors) and to investigate the oxygen release and uptake of doped catalysts under reducing and oxidising atmospheres – a direct window into the redox activity of the materials.

DLS & Zeta Potential (STABINO ZETA + FLEX Nanotrac)

Particle size and colloidal stability at a glance – the key parameters for (nano-)particle suspensions.

The combination of STABINO ZETA and NANOTRAC FLEX (both Microtrac MRB) covers two central quantities in nanoparticle characterisation: particle size distribution via dynamic light scattering (DLS) and electrostatic stability via zeta potential. Both parameters determine how nanoparticles behave in suspension and whether they remain stably dispersed or agglomerate. In our group, we characterise freshly synthesised nanoparticles directly after hydrothermal or sol-gel synthesis – and specifically optimise synthesis conditions for narrow, stable particle size distributions.

Impedance Spectroscopy – High-Temperature Custom Setup (high-temperature furnace by Novotherm)

Separation of ionic and electronic conductivity in solids as a function of temperature and atmosphere.

Our custom-built high-temperature impedance measurement station combines a tube furnace with controllable gas atmosphere, an impedance analyser and precision measurement electronics. Impedance spectroscopy separates ionic from electronic conductivity and provides information about interfacial processes, grain boundaries and bulk transport in solids. In our group, we use it to measure the electrical properties of perovskite ceramics (LaAlO₃, SrTiO₃) as a function of temperature and atmosphere – a direct window into the charge carrier transport mechanisms relevant to catalysis.

Hydrothermal Autoclaves

Reaction vessels for syntheses under elevated pressure and temperature – the foundation of hydrothermal synthesis.

Hydrothermal autoclaves are pressure-tight stainless steel vessels with PTFE inserts that enable syntheses at elevated pressure and temperatures up to approximately 250 °C. Under these conditions, oxides and ceramics can be crystallised directly from aqueous solution – without energy-intensive high-temperature steps. In our group, we use autoclaves for the hydrothermal synthesis of nanomaterials such as LaAlO₃ and SrTiO₃ nanoparticles, with particle size, morphology and degree of doping (e.g. Co²⁺, Cu²⁺) being precisely controlled via pressure, temperature and reaction time.

High-Performance Centrifuge (3-30KS, Sigma)

Fast, coolable phase separation via centrifugal force – for the separation and purification of (nano-)particles.

The Sigma 3-30KS is a high-performance refrigerated centrifuge with a wide speed range and touchscreen-based control. It efficiently separates solids from suspensions and enables gentle washing of sensitive nanoparticle precipitates. In our group, we use it for example to separate and purify synthesised nanoparticles – repeated centrifugation and redispersion reliably removes by-products such as nitrates, carbonates and excess ions from the product, ensuring the purity of the materials for all subsequent analyses.

Digital High-Temperature Muffle Furnace (Nabertherm)

Präzise kontrollierte Wärmebehandlung bis über 1000 °C – zentrales Gerät für Kalzinierung und Sintern keramischer Materialien.

The Thermo Scientific VACUtherm is a vacuum drying oven for precise thermal treatments under reduced pressure. Unlike convection ovens, it enables the drying of oxidation-sensitive or moisture-sensitive samples without uncontrolled phase formation. In our group, we use it for the gentle drying of precursor gels and powders after sol-gel synthesis or co-precipitation, before they enter the calcination furnace.

Vacuum Oven (VACUtherm, Thermo Scientific)

Thermic treatment under vacuum – sensitive drying without oxidation or uncontrolled phase formation

The Thermo Scientific VACUtherm is a vacuum drying oven for precise thermal treatments under reduced pressure. Unlike convection ovens, it enables the drying of oxidation-sensitive or moisture-sensitive samples without uncontrolled phase formation. In our group, we use it for the gentle drying of precursor gels and powders after sol-gel synthesis or co-precipitation, before they enter the calcination furnace.

The two furnaces mentioned here represent only a fraction of the many (muffle, sintering, …) furnaces available to our group.

Spin Coater (POLOS, SPS Europe)

Reproducible thin films spun with precision at up to 12,000 revolutions per minute.

Our spin coating system is equipped with a chemically resistant PTFE protective bowl. A solution or suspension is dispensed onto a substrate fixed to the vacuum chuck; centrifugal forces then distribute the liquid evenly and drive excess material outwards. With rotation speeds of up to 12,000 rpm and freely programmable speed and acceleration ramps, the resulting film thickness can be precisely adjusted in the nano- to micrometre range. In our group, we use the spin coater to deposit thin films from precursor or nanoparticle solutions – for example for the fabrication of homogeneous ceramic thin films on substrates or sample holders for optical characterisation, electrical measurements or as well-defined model catalysts.

Dip Coater

Large-area, uniform thin-film deposition via controlled immersion with defined immersion and withdrawal speeds.

Our dip coater is a precision motorised dip coating system housed in an enclosed protective cabinet. The substrate is immersed into a coating solution at a defined speed, dwells there for an adjustable time, and is then withdrawn at a precisely controlled speed. Film thickness follows directly from the withdrawal speed (Landau-Levich equation): slow withdrawal yields thinner films, faster withdrawal yields thicker films. Multiple dipping cycles enable targeted layer-by-layer build-up. Compared to spin coating, dip coating offers the advantage of being able to uniformly coat larger or irregularly shaped substrates. In our group, we use the dip coater, like the spin coater, to deposit thin films from precursor or nanoparticle solutions – for the fabrication of homogeneous ceramic thin films on substrates or sample holders for optical characterisation, electrical measurements or as well-defined model catalysts.

Compact Profile Catalysis Reactor (CPR-V5.3, Reacnostics)

Spatially and temporally resolved gas profiling and operando Raman spectroscopy simultaneously during a live catalysis experiment.

Our CPR-V5.3 is a fixed-bed reactor for spatially resolved operando characterisation under real catalytic conditions. At its core sits a long quartz tube filled with the catalyst material. Running coaxially through the catalyst bed is a thin stainless steel capillary with four laser-drilled micro-apertures, through which sample gas is continuously extracted directly from within the reaction bed. The measurement principle is elegant: the capillary remains stationary while the reactor tube is incrementally displaced – thereby generating a complete, spatially resolved gas concentration profile along the entire catalyst bed. The extracted gas is directly fed to a mass spectrometer or GC-MS and quantitatively analysed. An optical window integrated into the reactor body additionally enables simultaneous investigation of the catalyst bed by Raman spectroscopy – both spatially resolved along the bed and time-resolved during the ongoing reaction. In our group, we use the CPR-V5.3 to observe catalysts directly under reaction conditions: the combination of gas-phase profiling and operando Raman spectroscopy simultaneously provides information on conversion and product distribution along the reactor and on structural changes in the catalyst material – activation, deactivation and the dynamics of active sites become visible in real time.

3D Printer (Mars 5 Ultra + Wash & Cure Station, Elegoo)

Custom lab parts at the push of a button – high-resolution resin printing with integrated washing and UV curing directly in the workflow.

Our newest instrument: a Mars 5 Ultra resin printer. The printer is complemented by Elegoo Mercury stations: the wash station cleans freshly printed parts in an ethanol bath, completely removing uncured resin. The UV curing station then fully cures the parts. In our group, we use it to print custom laboratory components such as sample holders, reactor parts and adapters.