Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-55027 Zeitschriftenartikel Hoffmann, H; Paulisch, M C; Gebhard, M; Osiewacz, J; Kutter, M; Hilger, A; Arlt, T; Kardjilov, N; Ellendorff, B; Beckmann, F; Markötter, Henning; Luik, M; Turek, T; Manke, I; Roth, C Development of a Modular Operando Cell for X-ray Imaging of Strongly Absorbing Silver-Based Gas Diffusion Electrodes Metal-based gas diffusion electrodes are utilized in chlor-alkali electrolysis or electrochemical reduction of carbon dioxide, allowing the reaction to proceed at high current densities. In contrast to planar electrodes and predominantly 2D designs, the industrially required high current densities can be achieved by intense contact between the gas and liquid phase with the catalytically active surfaces. An essential asset for the knowledge-based design of tailored electrodes is therefore in-depth information on electrolyte distribution and intrusion into the electrode's porous structure. Lab-based and synchrotron radiography allow for monitoring this process operando. Herein, we describe the development of a cell design that can be modularly adapted and successfully used to monitor both the oxygen reduction reaction and the electrochemical reduction of CO2 as exemplary and currently very relevant examples of gas-liquid reactions by only minor modifications to the cell set-up. With the reported cell design, we were able to observe the electrolyte distribution within the gas diffusion electrode during cell operation in realistic conditions. IOP science 2022 Journal of The Electrochemical Society 169 4 044508 10.1149/1945-7111/ac6220 2022-06-15 OPUS4-56164 Zeitschriftenartikel Van Tran, K.; Woracek, R.; Kardjilov, N.; Markötter, Henning; Abou-Ras, D.; Puplampu, S.; Förster, C.; Penumadu, D.; Dahlberg, C. F. O.; Banhart, J.; Manke, I. Torsion of a rectangular bar: Complex phase distribution in 304L steel revealed by neutron tomography Metastable austenitic stainless steel (304L) samples with a rectangular cross-section were plastically deformed in torsion during which they experienced multiaxial stresses that led to a complex martensitic phase distribution owing to the transformation induced plasticity effect. A three-dimensional characterization of the phase distributions in these cm-sized samples was carried out by wavelength-selective neutron tomography. It was found that quantitatively correct results are obtained as long as the samples do not exhibit any considerable preferential grain orientation. Optical microscopy, electron backscatter diffraction, and finite element modeling were used to verify and explain the results obtained by neutron tomography. Altogether, neutron tomography was shown to extend the range of microstructure characterization methods towards the meso- and macroscale. Elsevier Ltd. 2022 Materials & Design 222 111037 urn:nbn:de:kobv:b43-561649 10.1016/j.matdes.2022.111037 https://creativecommons.org/licenses/by/4.0/deed.de 2022-11-03 OPUS4-56457 Zeitschriftenartikel Zhang, Z.; Dong, K.; Mazzio, K. A.; Hilger, A.; Markötter, Henning; Wilde, F.; Heinemann, T.; Manke, I.; Adelhelm, P. Phase transformation and microstructural evolution of CuS electrodes in solid-state batteries probed by in situ 3D X-ray tomography Copper sulfide shows some unique physico-chemical properties that make it appealing as a cathode active material (CAM) for solid-state batteries (SSBs). The most peculiar feature of the electrode reaction is the reversible formation of μm-sized Cu crystals during cycling, despite its large theoretical volume change (75%). Here, the dynamic microstructural evolution of CuS cathodes in SSBs is studied using in situ synchrotron X-ray tomography. The formation of μm-sized Cu within the CAM particles can be clearly followed. This process is accompanied by crack formation that can be prevented by increasing the stack pressure from 26 to 40 MPa. Both the Cu inclusions and cracks show a preferential orientation perpendicular to the cell stack pressure, which can be a result of a z-oriented expansion of the CAM particles during lithiation. In addition, cycling leads to a z-oriented reversible displacement of the cathode pellet, which is linked to the plating/stripping of the Li counter electrode. The pronounced structural changes cause pressure changes of up to 6 MPa within the cell, as determined by operando stack pressure measurements. Reasons for the reversibility of the electrode reaction are discussed and are attributed to the favorable combination of soft materials. Wiley VHC-Verlag 2022 Advanced Energy Materials 2203143 1 12 urn:nbn:de:kobv:b43-564577 10.1002/aenm.202203143 https://creativecommons.org/licenses/by/4.0/deed.de 2022-12-05 OPUS4-54597 Zeitschriftenartikel Ziesche, R.F.; Hack, J.; Rasha, L.; Maier, M.; Tan, C.; Heenan, T.M.M.; Markötter, Henning; Kardjilov, N.; Manke, I.; Kockelmann, W.; Brett, D.J.L.; Shearing, P.R. High-speed 4D neutron computed tomography for quantifying water dynamics in polymer electrolyte fuel cells In recent years, low-temperature polymer electrolyte fuel cells have become an increasingly important pillar in a zero-carbon strategy for curbing climate change, with their potential to power multiscale stationary and mobile applications. The performance improvement is a particular focus of research and engineering roadmaps, with water management being one of the major areas of interest for development. Appropriate characterisation tools for mapping the evolution, motion and removal of water are of high importance to tackle shortcomings. This article demonstrates the development of a 4D high-speed neutron imaging technique, which enables a quantitative analysis of the local water evolution. 4D visualisation allows the time-resolved studies of droplet formation in the flow fields and water quantification in various cell parts. Performance parameters for water management are identified that offer a method of cell classification, which will, in turn, support computer modelling and the engineering of next-generation flow field designs. London Nature Publishing Group UK 2022 Nature Communications 13 1 1616 urn:nbn:de:kobv:b43-545978 10.1038/s41467-022-29313-5 https://creativecommons.org/licenses/by/4.0/deed.de 2022-04-06 OPUS4-54431 Zeitschriftenartikel Sun, F.; Wang, C.; Osenberg, M.; Dong, K.; Zhang, S.; Yang, C.; Wang, Y.; Hilger, A.; Zhang, J.; Dong, S.; Markötter, Henning; Manke, I.; Cui, G. Clarifying the Electro-Chemo-Mechanical Coupling in Li10SnP2S12 based All-Solid-State Batteries A fundamental clarification of the electro-chemo-mechanical coupling at the solid-solid electrode|electrolyte interface in all-solid-state batteries (ASSBs) is of crucial significance but has proven challenging. Herein, (synchrotron) X-ray tomography, electrochemical impedance spectroscopy (EIS), time-of-flight secondary-ion mass spectrometry (TOF-SIMS), and finite element analysis (FEA) modeling are jointly used to decouple the electro-chemo-mechanical coupling in Li10SnP2S12-based ASSBs. Non-destructive (synchrotron) X-ray tomography results visually disclose unexpected mechanical deformation of the solid electrolyte and electrode as well as an unanticipated evolving behavior of the (electro)chemically generated interphase. The EIS and TOFSIMS probing results provide additional information that links the interphase/electrode properties to the overall battery performance. The modeling results complete the picture by providing the detailed distribution of the mechanical stress/strain and the potential/ionic flux within the electrolyte. Collectively, these results suggest that 1) the interfacial volume changes induced by the (electro)chemical reactions can trigger the mechanical deformation of the solid electrode and electrolyte; 2) the overall electrochemical process can accelerate the interfacial chemical reactions; 3) the reconfigured interfaces in turn influence the electric potential distribution as well as charge transportation within the SE. These fundamental discoveries that remain unreported until now significantly improve the understanding of the complicated electro-chemo-mechanical couplings in ASSBs. Wiley VHC-Verlag 2022 Advanced Energy Materials 2103714 10.1002/aenm.202103714 2022-03-09 OPUS4-53836 Zeitschriftenartikel Duan, K.; Zhu, L.; Li, M.; Xiao, L.; Bevilacqua, N.; Eifert, L.; Manke, I.; Markötter, Henning; Zhang, R.; Zeis, R.; Sui, P. -C. Multiphase and Pore Scale Modeling on Catalyst Layer of High-Temperature Polymer Electrolyte Membrane Fuel Cell Phosphoric acid as the electrolyte in high-temperature polymer electrolyte membrane fuel cell plays an essential role in ist performance and lifetime. Maldistribution of phosphoric acid in the catalyst layer (CL) may result in performance degradation. In the present study, pore-scale simulations were carried out to investigate phosphoric acid's multiphase flow in a cathode CL. A reconstructed CL model was built using focused ion beam-SEM images, where distributions of pore, carbon support, binder, and catalyst particles can be identified. The multi-relaxation time lattice Boltzmann method was employed to simulate phosphoric Acid invading and leaching from the membrane into the CL during the membrane electrode assembly fabrication process. The predicted redistribution of phosphoric acid indicates that phosphoric acid of low viscosity or low wettability is prone to leaching into the CL. The effective transport properties and the active electrochemical active surface area (ECSA) were computed using a pore-scale model. They were subsequently used in a macroscopic model to evaluate the cell performance. A parametric study shows that cell performance first increases with increasing phosphoric acid content due to the increase of ECSA. However, further increasing phosphoric acid content results in performance degradation due to mass transfer limitation caused by acid flooding. IOP Science 2021 Journal of The Electrochemical Society 168 5 054521 10.1149/1945-7111/abff03 2021-11-29 OPUS4-53842 Zeitschriftenartikel Wu, Y.; Lu, X.; Cho, J.I.S.; Rasha, L.; Whiteley, M.; Neville, T. P.; Ziesche, R.; Kardjilov, N.; Markötter, Henning; Manke, I.; Zhang, X.; Shearing, P. R.; Brett, D. J. L. Multi-length scale characterization of compression on metal foam flow-field based fuel cells using X-ray computed tomography and neutron radiography The mechanical compression of metal foam flow-field based polymer electrolyte fuel cells (PEFCs) is critical in determining the interfacial contact resistance with gas diffusion layers (GDLs), reactant flow and water management. The distinct scale between the pore structure of metal foams and the entire flow-field warrant a multilength scale characterization that combines ex-situ tests of compressed metal foam samples and in-operando analysis of operating PEFCs using X-ray computed tomography (CT) and neutron radiography. An optimal 'medium' compression was found to deliver a peak power density of 853 mW/cm². The X-ray CT data indicates that the compression process significantly decreases the mean pore size and narrows the pore size distribution of metal foams. Simulation results suggest compressing metal foam increases the pressure drop and gas velocity, improving the convective liquid water removal. This is in agreement with the neutron imaging results that demonstrates an increase in the mass of accumulated liquid water with minimum compression compared to the medium and maximum compression cases. The results show that a balance between Ohmic resistance, water removal capacity and parasitic power is imperative for the optimal performance of metal foam based PEFCs. Elsevier Ltd. 2021 Energy Conversion and Management 239 10 113785 10.1016/j.enconman.2020.113785 2021-11-29 OPUS4-53077 Zeitschriftenartikel Hilger, A.; Kardjilov, N.; Lange, A.; Kupsch, Andreas; Hentschel, M. P.; Manke, I. Neutron darkfield imaging of fiber composites While X-ray based darkfield imaging with grating interferometers is already widely used, darkfield imaging with neutrons has still a relatively small user community focused mostly on magnetic materials. Here, we demonstrate the application of neutron darkfield imaging byTalbot-Lau type grating interferometry to fiber reinforced plastics. Common carbon and glass fiber composites have been investigated including characteristic damage structures. The darkfield images show a strong signal response caused by fiber delamination, suitable fiber direction, particles, pores and cracks. The basic principles of neutron darkfield imaging applied to fiber composites are highlighted. Berlin De Gruyter 2021 Materials Testing 63 7 623 629 10.1515/mt-2020-0103 2021-08-11 OPUS4-52089 Zeitschriftenartikel Ziesche, R. F.; Robinson, J. B.; Markötter, Henning; Bradbury, R.; Tengattini, A.; Lenoir, N.; Helfen, L.; Kockelmann, W.; Kardjilov, N.; Manke, I.; Brett, D. J. L.; Shearing, P. R. Editors' Choice—4D Neutron and X-ray Tomography Studies of High Energy Density Primary Batteries: Part II. Multi-Modal Microscopy of LiSOCl2 Cells The ability to track electrode degradation, both spatially and temporally, is fundamental to understand performance loss during operation of lithium batteries. X-ray computed tomography can be used to follow structural and morphological changes in electrodes; however, the direct detection of electrochemical processes related to metallic lithium is difficult due to the low sensitivity to the element. In this work, 4-dimensional neutron computed tomography, which shows high contrast for lithium, is used to directly quantify the lithium diffusion process in spirally wound Li/SOCl2 primary cells. The neutron dataset enables the quantification of the lithium transport from the anode and the accumulation inside the SOCl2 cathode to be locally resolved. Complementarity between the collected neutron and X-ray computed tomographies is shown and by applying both methods in concert we have observed lithium diffusion blocking by the LiCl protection layer and identified all cell components which are difficult to distinguish using one of the methods alone. IOP Science 2020 Journal of the Electrochemical Society 167 140509 urn:nbn:de:kobv:b43-520890 10.1149/1945-7111/abbfd9 https://creativecommons.org/licenses/by/4.0/deed.de 2021-02-10 OPUS4-52091 Zeitschriftenartikel Bevilacqua, N.; Asset, T.; Schmid, M. A.; Markötter, Henning; Manke, I.; Atanassov, P.; Zeis, R. Impact of catalyst layer morphology on the operation of high temperature PEM fuel cells Electrochemical impedance spectroscopy (EIS) is a well-established method to analyze a polymer electrolyte membrane fuel cell (PEMFC). However, without further data processing, the impedance spectrum yields only qualitative insight into the mechanism and individual contribution of transport, kinetics, and ohmic losses to the overall fuel cell limitations. The distribution of relaxation times (DRT) method allows quantifying each of these polarization losses and evaluates their contribution to a given electrocatalyst's depreciated performances. We coupled this method with a detailed morphology study to investigate the impact of the 3D-structure on the processes occurring inside a high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC). We tested a platinum catalyst (Pt/C), a platinum-cobalt alloy catalyst (Pt3Co/C), and a platinum group metal-free iron-nitrogen-carbon (Fe-N-C) catalyst. We found that the hampered mass transport in the latter is mainly responsible for its low performance in the MEA (along with its decreased intrinsic performances for the ORR reaction). The better performance of the alloy catalyst can be explained by both improved mass transport and a lower ORR resistance. Furthermore, single-cell tests show that the catalyst layer morphology influences the distribution of phosphoric acid during conditioning. Elsevier Ltd. 2021 Journal of Power Sources Advances 7 100042 urn:nbn:de:kobv:b43-520917 10.1016/j.powera.2020.100042 https://creativecommons.org/licenses/by-nc-nd/4.0/deed.de 2021-02-10