Highlights:

• Fully equipped synthesis laboratory
• Tube furnaces for synthesis or catalyst calcination under controlled gas atmosphere and flow
• Physical characterization of synthesized materials (TGA-MS, DSC, BET, SEM/EDX, XPS, XRD)

References:

• Hartig-Weiss, A.; Miller, M.; Beyer, H.; Schmitt, A.; Siebel, A.; Freiberg, A. T. S.; Gasteiger, H. A.; El-Sayed, H. A. / ACS Appl. Nano Mater., 2020, 3, 2185-2196, -  DOI
• Geppert, T. N.; Bosund, M.; Putkonen, M.; Stühmeier, B. M.; Pasanen, A. T.; Heikkilä, P.; Gasteiger, H. A.; El-Sayed, H. A. / J. Electrochem. Soc., 2020, 167, article # 084517 (Open Access) - DOI
• Stühmeier, B. M.; Selve, S.; Patel, M. U. M.; Geppert, T. N.; Gasteiger, H. A.; El-Sayed, H. A. / ACS Applied Energy Materials, 2019, 2, 8, 5534-5539 (Open Access) – DOI
• Madkikar, P.; Menga, D.; Harzer, G. S.; Mittermeier, T.; Siebel, A.; Wagner, F. E.; Merz, M.; Schuppler, S.; Nagel, P.; Munoz-Garcia, A. B.; Pavone, M.; Gasteiger, H. A.; Piana, M. / J. Electrochem. Soc., 2019, 166(7), F3032-F3043 (Open Access) - DOI

Highlights:

• In-house electrode fabrication parting from solvent-based catalyst inks using an Erichsen Control Coater
• Coating process via the Mayer-rod technique adapted for the desired wet film thickness
• Tuning of the catalyst layer properties by varying the solid and liquid composition of the ink

References:

Ink Solvent Dependence of the Ionomer Distribution in the Catalyst Layer of a PEMFC / Orfanidi, A.; Rheinländer, P. J.; Schulte, N.; Gasteiger, H. A. / J. Electrochem. Soc., 2018, 165, F1254–F1263 (Open Access) – DOI

The cryo cross section polisher (IB-19520 CCP) is the ideal device to prepare samples for scanning electron microscopy (SEM). The argon ion beam allows for smoother cross sections with less distortion compared to mechanical polishing methods for various kind of samples. Sensitive samples can additionally be cooled down with liquid nitrogen during polishing. To achieve the best results, varying polishing settings can be adjusted to the sample type.

Highlights:

• Clean polished cross section of hard, soft, and composite material
• Preparation of LIB electrode and MEA cross sections for SEM analysis
• Cryo-polishing to minimize beam damage for sensitive materials (e.g., binder etc.)

Highlights:

• Fully automated test stations for MEA characterization and long-term testing of single cells
• Equipped with a 120 A load bank and a Gamry potentiostat with an optional 30 A booster
• 5 cm² and 50 cm² single cell hardwares with electrical heating system
• Evaluation of fuel cell performance as a function of cell voltage, temperature and pressure
• Simulation of accelerated stress tests (ASTs) and start-up/shut-down (SUSD) procedures as well as testing of recovery strategies

References:

• Cathode Loading Impact on Voltage Cycling Induced PEMFC Degradation: A Voltage Loss Analysis / Harzer, G. S.; Schwämmlein, J. N.; Damjanović, A. M.; Ghosh, S.; Gasteiger, H. A. / J. Electrochem. Soc., 2018, 165, F3118–F3131 (Open Access) – DOI
• PEM Fuel Cell Start-Up/Shut-Down Losses vs Relative Humidity: The Impact of Water in the Electrode Layer on Carbon Corrosion / Mittermeier, T.; Weiß, A.; Hasché, F.; Gasteiger, H. A. / J. Electrochem. Soc., 2018, 165, F1349–F1357 (Open Access) – DOI

Via physical adsorption/desorption of inert gases (Kr, N), the surface and the porosity of the measured material can be determined.

Mercury intrusion porosimetry (MIP) is used to examine the pore structure of a sample. Since mercury does not wet most substances (contact angle greater than 90°), it has to be forced to fill open pore space by applying an external pressure. According to the Washburn equation, this pressure correlates inversely to the pore diameter, which can be accessed from roughly 200 µm down to 3 nm by MIP. The more than five-decade span of pore sizes enables the application for a wide range of powders (e.g., cathode active materials for lithium-ion batteries) and solids (e.g. battery electrodes, catalyst layers and gas diffusion media of fuel cells and electrolyzers). Targeted parameters are the pore size and its distribution, pore volume, bulk and skeletal density, and finally the porosity of the sample.

Highlights:

• Analysis of exhaust gases
• Crossover measurements
• Investigation of system degradation during e.g. start/stop events

Highlights:

• Portable gas flow/humidification system with Biologic VSP-300 Potentiostat (2 channels, 20 A)
• Water pump for electrolysis operation
• Custom-made operando 5 cm² single cell with x-ray windows
• Designed for mechanistic studies of noble- and transition metal catalysts with x-ray absorption spectroscopy (XAS) in operando mode

References:

• A. Siebel, Y. Gorlin, J. Durst, O. Proux, F. Hasché, M. Tromp, H. A. Gasteiger, ACS Catalysis, 6, 7326-7334 (2016) - DOI

Highlights:

• Fast screening of different synthesized catalysts based on their activity for the hydrogen oxidation/evolution (HOR/HER) and oxygen reduction/evolution (ORR/OER) reactions
• Setups adapted for acidic, alkaline and aprotic electrolytes
• Small-scale testing with few mg of material
• Investigation of different electrochemical deposition reactions

References:

• Hartig-Weiß, A.; Tovini, M. F.; Gasteiger, H. A.; El-Sayed, H. A. / ACS Applied Energy Materials, 2020 - DOI
• Schwämmlein, J. N.; Loichet Torret, P. A.; Gasteiger, H. A.; El-Sayed, H. / Nature Scientific Reports, 2020, 59(10) (Open Access) - DOI
• Tok, G. C.; Freibert, A. T. S.; Gasteiger, H. A.; Hess, C. R. / ChemCatChem, 2019 (Open Access) - DOI
• Stühmeier, B. M.; Selve, S.; Patel, M. U. M.; Geppert, T. N.; Gasteiger, H. A.; El-Sayed, H. A. / ACS Applied Energy Materials, 2019, 2, 8, 5534-5539 (Open Access) - DOI

The table-top SEM Jeol JCM6000 (left-side) with the possibility of gold-sputtering with Jeol JFC-1300 (right side) is located at TEC. The SEM is a useful tool for visual analysis of e.g. MEAs or fuel cell/battery electrodes on a micrometer scale. Additionally the composition of the electrode can be determined via elemental analysis using the built-in EDX probe.

X-ray photoelectron spectroscopy (XPS) is a surface-sensitive quantitative spectroscopic technique. With this method, it is possible to quantify the elemental composition, empirical formula, chemical state and electronic state of the elements that are within a range of ~5 nm of the surface.

X-ray powder diffraction (XRD) is an analytical technique used for phase identification of a crystalline material and can provide information on unit cell dimensions.

• Determination of stress-strain curves of various materials
• Estimation of material compression in various setups (e.g. fuel cells)