TY - CONF A1 - Weber, Mike T1 - Reproducing and discussion of mechanisms in the contact area between metallic seals and flange during aging by finite element analysis (FEA) N2 - When the first site-specific interim storage licenses for DPCs (dual purpose casks), loaded with spent nuclear fuel or vitrified high-level waste from reprocessing were issued, a duration of 40 years was considered for interim storage license application and the long-term safety assessment of casks. In the meantime, the availability of a final repository is further delayed by several decades and thus interim storage for more than a century becomes a necessity. To assess the long-term performance of the typically used metal seals (e.g. Helicoflex), consisting of a helical spring (Nimonic), an inner stainless steel liner and an outer liner made from silver or aluminum, several experimental programs were conducted and are still ongoing. The investigated metal seals are typically mounted in mock-up flange systems and stored at increased temperatures to accelerate the aging process. In certain intervals the remaining seal force, the useable resilience and the corresponding leakage rate are determined. BAM has accompanied such programs for many years and started independent investigations in 2009. Although the remaining seal force is often used as “…one of the key parameters regarding sealing performances over time…” the presented results so far have shown that the courses of the leakage rate and the remaining seal force do not always correlate as expected. In 2016 BAM firstly published results of seals with aluminum liners where the measured leakage rate started to rise after a quite short time period (< 1 year) at 150 °C, although the seal force decreased only slightly compared to the previous measurement. After exceeding the required leakage rate of 10-8 Pa*m3/s it decreased again to acceptable values in the further course of aging. With reference to already published works, BAM has developed a new detailed ABAQUS finite-element (FE) model to represent the behavior of the seal mounted in the mock-up flange during aging, mainly characterized by the creeping of the outer liner. The main goal of the numerical simulation is to reproduce and understand the changing distribution of contact stresses (outer liner/flange) during aging and to discuss if and how it could be causative for the observed early breach of the leak tightness criteria and its later recovery. T2 - PATRAM 2025, 21st International Symposium on the Packaging and Transportation of Radioactive Materials CY - San Antonio, Texas, USA DA - 27.07.2025 KW - Finite element analysis KW - Metallic seals KW - Aging KW - Contact area PY - 2025 AN - OPUS4-63883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg T1 - Photolytically and Thermally Initiated Destruction N2 - Casks for storage and transportation of used fuel rods of radioactive material are equipped with polyethylene (PE) for improved neutron flux shielding. The embedded PE structures are additionally exposed to gamma radiation and heat flow due to the specific high activity of the fission products. 60Co γ-radiation and heat load experiments at 125°C has been performed to evaluate PE degradation during the ageing process. FAR-FTIR-experiments were subsequently performed at differently aged PE test samples to characterize the oxidation process and morphological changes in the samples during the ageing at 125°C. T2 - 11'th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 04.12.2019 KW - FTIR KW - High Molecular Polyethylene KW - Ageing PY - 2019 AN - OPUS4-49988 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias T1 - Comparison of ageing behaviour of O-ring seals under hydrogen and air N2 - Elastomeric seals are essential components in the infrastructure which prevent leakage of gas and proper function of technical devices and are therefore highly safety relevant. For proper function a remaining resilience and tolerance to pressure changes is required. The ageing of elastomers is an undesirable but inevitable process leading to a limited lifetime of rubber products such as seals. Independent of the application, as e.g. automotive, piping or container applications, a long lifetime or at least a timely exchange of a seal before occurrence of critical failure is desired. Hydrogen is a key element for the energy turnaround and therefore the compatibility of seals with hydrogen is essential. In addition to the effect of hydrogen uptake and release, which might also cause destructive effects such as rapid gas decompression, ageing at high temperature under hydrogen atmosphere is of interest too. Most of the existing work is addressing the performance of new materials and comprises only very limited investigations concerning long-term use and the behaviour of aged materials in contact with hydrogen. As ageing can lead to substantial changes of material properties, it must be evaluated whether these changes are beneficial or deteriorating for the component function. In this work we present and compare results of the characterisation of three sealing materials (EPDM, HNBR, FKM) after ageing at high temperature under hydrogen and air. Despite the common assumption that ageing under hydrogen atmosphere should be less severe for the material in comparison to air ageing, this is not the case for every material. T2 - RubberCon 2023 CY - Edinburgh, Scotland DA - 09.05.2023 KW - Hydrogen KW - Ageing KW - Seal PY - 2023 AN - OPUS4-58178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg T1 - Photolytically and Thermally Initiated Destruction on the Stability of (Ultra)High Molecular Polyethylene N2 - THz and mid IR spectroscopy of high-molecular PE (HMW) and ultra high-molecular PE (UHMW) reveals modifications of the molecular structure. Characteristic absorption bands are changed if the two materials are exposed by γ-Co60 radiation up to 600 kGy and subsequently stored at an annealing temperature of 398 K until for 729 days. UHMW-PE and HMW-PE behave differently during the ageing process because of their molecular weight and inherent structure distinctions. The spectroscopic data offer characteristic absorption bands, which have been used to describe the complete ageing process in more detail. For instance, the integral absorption in the B1u THz-region can be used to describe quantitatively the reduction of crystallinity. The formation of trans vinylene unsaturation and the decay of vinyl during ageing can be observed in detail in the mid IR range. T2 - 9th International Workshop on Terahertz Technology and Applications CY - Kaiserslautern, Germany DA - 03.03.2020 KW - Degradation KW - MID IR Spectroscopy PY - 2020 AN - OPUS4-50555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gröke, Carsten T1 - Requirements for Package Design Testing and Quality Assurance Measures for Packages not Requiring Competent Authority Design Approval N2 - Übersicht über die gefahrgutrechtlichen Anforderungen zur Bauartprüfung und dem Qualitätsmanagement für Verpackungen für nicht zulassungspflichtige Versandstücke. T2 - KONTEC 2019 CY - Dresden, Germany DA - 27.03.2019 KW - Bauartprüfung KW - Qualitätsmanagement KW - Nicht zulassungspflichtig PY - 2019 AN - OPUS4-56352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gräf, S. T1 - Large-area fabrication of low- and high-spatial-frequency laser-induced periodic surface structures on carbon fibers N2 - The properties of fiber-reinforced polymers (CFRP) or concretes (ECC) strongly depend on the interface between the fiber and the surrounding matrix. Different methods such as plasma oxidation, chemical or electrolytic etching and chemical vapor deposition have been investigated to increase, for example, the bonding strength. The present study deals with the functionalization of the fiber surface based on laser-induced periodic surface structures (LIPSS). They can be characterized as a modulation of the surface topography on the nano- and microscale that results from the irradiation of the surface with linearly polarized laser radiation close to the ablation threshold. According to their spatial period, LIPSS are classified into low-spatial frequency LIPSS (LSFL) and high-spatial frequency LIPSS (HSFL). The great potential of both types of LIPSS structures regarding functional surface properties was demonstrated in numerous investigations. The objective of the present study was the homogenous manufacturing of both types of LIPSS on large areas of carbon fiber arrangements without damage. The results are discussed based on a detailed analysis of the topographic and chemical surface properties. T2 - 15th International Conference on Laser Ablation (COLA 2019) CY - Hawaii, USA DA - 08.09.2019 KW - Laser-induced periodic surface structures (LIPSS) KW - Carbon fibers KW - Femtosecond laser ablation KW - Surface functionalization PY - 2019 AN - OPUS4-49676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Quercetti, Thomas T1 - Drop Testing of a New Package Design for the Transport of SNF from German Research Reactors N2 - A new dual purpose cask design was developed for the safe transport and interim storage of spent fuel elements of German research reactors. In the framework of the safety assessment within the package approval procedure the Bundesanstalt für Materialforschung und –prüfung (BAM) as competent authority performed a series of drop tests according with the IAEA Transport Regulations. The package consists of a cylindrical thick-walled ductile cast iron cask body closed by a bolted lid system with metallic seals. A lid and bottom sided impact limiter consisting of a wood/steel construction limit the mechanical impact loading. The full-scale test specimen was equipped with a basket and assembled with dummy-fuel elements. The package and test specimen, respectively have a total mass of approximately 24 metric tons. The mechanical drop test program included three 9m free drop tests, in horizontal, vertical and oblique cask orientation onto the lid system. Additionally, a 1m-puncture bar drop test followed the horizontal drop test to consider an IAEA-drop test sequence. The horizontal and vertical drop tests were performed at a temperature of minus 40°C. During the oblique drop test the upper impact limiter was heated up to +80°C. The tests were conducted onto an unyielding target, fulfilling the IAEA requirements. The test specimen was considerably instrumented with strain gauges and accelerometers. Transient strains at selected locations of the inner and outer container walls, of the primary and secondary lid, as well as of the corresponding lid bolts were measured during the drop tests. Furthermore, decelerations in different locations at the cask body and the lids were measured. The complex geometrical deformation of the impact limiters due to the impact were determined by optical 3D- measurements. Before and after the drop tests the leakage rate of the lid system was determined by helium leakage testing. The experimental results contribute to the evaluation of the package response to mechanical tests, demonstrating safety under normal and accident conditions of transport and especially to the verification of the dynamic finite-element model of the package used in the package design safety report. T2 - PATRAM 2019 CY - New Orleans, LA, USA DA - 04.08.2019 KW - SNF KW - Drop testing KW - New package design PY - 2019 AN - OPUS4-50623 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Markötter, Henning A1 - Dayani, Shahabeddin T1 - Tomographic Imaging of Battery Materials at BAMline (Bessy II) N2 - Different scientific questions in battery research can be addressed by synchrotron X-Ray imaging. The BAMline at the 3rd generation synchrotron X-ray source BESSY II has been supporting researchers in a wide range of research areas for over 20 years. Being a non-destructive characterization method, synchrotron X-ray imaging, in particular tomography (SXCT), plays a particularly important role in structural characterization. This poster gives few examples from battery research conducted at BAMline. As a non-destructive characterization method, synchrotron X-ray imaging, especially tomography with hard X-Rays, plays an important role in structural 3D characterization. The upgraded dual multilayer monochromator offers flexibility by providing different energy spectra to optimize flux and energy resolution as desired. The upgraded detector (in white beam configuration, equipped with an sCMOS camera) allows the higher flux to be exploited with reduced readout times. Shorter tomographic acquisition times in the range of seconds are now possible. Hence, in-situ and operando examinations are routinely available. An integrated slip ring allows continuous rotation of the sample stage for ease of wiring. The pink beam option allows tomographic observation of processes occurring in the time domain of a few seconds with a resolution down to ~ 1 µm. The in-situ capabilities include electrochemical cycling, mechanical load (tension and compression) and heating up to 1100°C. Ergebnisse The method, equipment, data handling pipeline as well as various examples from battery research conducted at BAMline are presented and discussed. In particular, the 3D morphology and distribution of deposited Li within the widely used Celgard® 2325 polyolefin separator are visualized in situ, thus promoting the understanding of the short-circuiting process of Li metal batteries. In addition, we also visualized and quantified the spatial distribution of Li depositions inside a porous carbon host to unravel the deposition behavior that can hardly be probed by surface imaging techniques. The Li electrodeposition behavior found here could help to promote the understanding and development of surface modifications related to Li anodes, separators as well as novel 3D geometry electrode designs for accommodation of Li depositions and alleviation of volumetric changes. T2 - Batterieforum Deutschland CY - Berlin, Germany DA - 18.01.2023 KW - BAMline KW - X-ray tomography KW - Li-ion battery PY - 2023 AN - OPUS4-56909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stargardt, Patrick T1 - Comparison of design concepts for ceramic oxide thermoelectric multilayer generators N2 - Multilayer thermoelectric generators are a promising perspective to the conventional π-type generators. Ceramic multilayer technology is well established for production of microelectronics and piezo-stacks. Key features of ceramic multilayer technology are full-automation, cost-effectiveness, and the co-firing of all materials in one single step. This requires similar sintering temperatures of all used materials. The development of multilayer thermoelectric generators is a subject of current research due to the advantages of this technology. One of the challenges is the compatibility of the different materials with respect to the specific design. The presented study compares three different designs of multilayer generators based on a given set of material properties. Dualleg, unileg and transverse multilayer generators are compared to conventional π-type generators., the designs are evaluated regarding the expected maximum output power and power density using analytical calculations and FEM simulations. Additionally, the complexity of the production process and material requirements are assessed and design optimizations to simplify production are discussed. Besides the theoretical aspects, unileg multilayer generator prototypes were produced by tape-casting and pressure-assisted sintering. These prototypes are compared to other multilayer generators from literature regarding the power factors of the used material system and the power density. Improvements of the power output by design optimizations are discussed T2 - 18th European Conference on Thermoelectrics CY - Barcelona, Spain DA - 13.09.2022 KW - Thermoelectric oxides KW - Thermoelectric generator design PY - 2022 AN - OPUS4-55820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lucaßen, J. T1 - Bottom-up grown CISe micro absorber arrays: microstructure analysis and solar cell integration N2 - A reduction of critical raw materials like indium and gallium in chalcopyrite thin-film solar cells is aimed for the micro-concentrator concept. Bottom-up grown micro absorbers for operation under light concentration on the micrometer scale allow improved heat dissipation. T2 - 41st European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC 2024) CY - Vienna, Austria DA - 23.09.2024 KW - Laser-assisted MO-CVD KW - CISe micro-absorber KW - Micro solar cell arrays KW - Solar cell efficiency PY - 2024 AN - OPUS4-62075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dayani, Shahabeddin T1 - Quantification of Deep Discharge Mechanism in a Li-Ion Battery by operando X-ray Computed Tomography N2 - Lithium-ion batteries connected in series are prone to an electrical abuse called over discharge. We present a comprehensive investigation of the over discharge abuse mechanism in lithium-ion batteries using operando non-destructive imaging. The study focuses on understanding the behavior of copper dissolution and deposition during over discharge, which can lead to irreversible capacity loss and internal short circuits. By utilizing synchrotron X-ray computed tomography (SXCT), the concentration of dissolved and deposited copper per surface area is quantified as a function of depth of discharge (DoD). T2 - HZB user meeting CY - Berlin, Germany DA - 22.06.2023 KW - Non-destructive testing PY - 2023 AN - OPUS4-57793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Markötter, Henning T1 - Synchrotron X-Ray Tomography Techniques at BAMline N2 - A recent upgrade of key equipment of the BAMline widens its imaging capabilities: shorter scan acquisition times are now possible, in situ and operando studies can now be routinely performed, and different energy spectra can easily be set up. In fact, the upgraded double-multilayer monochromator brings full flexibility by yielding different energy spectra to optimize flux and energy resolution as desired. T2 - HZB User Meeting CY - Online meeting DA - 08.12.2022 KW - BAMline KW - X-ray imaging KW - Tomography PY - 2022 AN - OPUS4-56568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Sophie T1 - Optimization of Solid-State-Reactions of Calcium Cobaltite Ca3Co4O9 N2 - Calcium cobaltite is a promising p-type oxide thermoelectric material for high temperature applications due to its high figure of merit between 600 °C and 900 °C in air. The solid-state-reaction is well known for large scale powder synthesis of functional materials. As a high temperature process, the powder synthesis consumes a lot of energy. In different studies, different synthesis conditions were used for the preparation of calcium cobaltite powder. This study showed that a higher energy input (elevated temperatures, longer dwell times, or repeated calcinations) during powder synthesis does not increase but decrease the Seebeck coefficient and the electrical conductivity. The same correlation was determined for the densification. As a higher energy input leads to a larger grain size and therefore to a reduced sinter activity, it can be concluded that the thermoelectric properties are correlated with the sinter activity of the powder. These results can be used to minimize the energy demand for the powder synthesis of Ca₃Co₄ O₉. T2 - 14th European Conference on Thermoelectrics CY - Lisbon, Portugal DA - 20.09.2016 KW - Thermoelectrics KW - Solid-State-Reaction KW - Calcium cobaltite PY - 2016 AN - OPUS4-37543 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sagradov, Ilja T1 - Long-term tests and numerical simulations on metal seals based on continuous force measurement in compressed state N2 - In Germany, the search for a disposal site for heat-generating radioactive waste will take decades longer than originally assumed. Transport and storage casks must therefore ensure safe containment for extended interim storage periods, possibly over 100 years. In order to maintain the required leak tightness, spring core metal seals with aluminum or silver cladding are used. As sealing force decreases over time, BAM has been conducting tests for over 15 years to prove their long-term reliability. This work - a joint project of BASE and BAM - aims to obtain additional material data using a new device for continuous measurement of compression force over time and temperature for lifetime prediction models and is supported by FEM simulations. Initial tests on aluminum and silver seals have been completed, and first results are presented. T2 - safeND 2025 CY - Berlin, Germany DA - 17.09.2025 KW - Interim storage KW - Metal seal KW - Restoring force PY - 2025 AN - OPUS4-64991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grelle, Tobias T1 - Creep Investigations on Aluminum Seals for Application in Radioactive Waste Containers N2 - In Germany spent nuclear fuel (SNF) and high level radioactive waste (HLW) are stored in interim storage containers with double lid systems. Those lids are equipped with metal seals (e.g. Helicoflex®) that ensure the safe enclosure of the inventory. Being licensed for up to 40 years of interim storage the evaluation of the long-term behavior of the seals is necessary, taking into account storage conditions, decay heat and possible mechanical loads. T2 - International Conference on Aluminum Alloys CY - Montreal, Canada DA - 17.06.2018 KW - Metal seal KW - Creep KW - Long-term behavior PY - 2018 AN - OPUS4-45843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sagradov, Ilja T1 - Long-term tests on metal seals using continuous force measurement in compressed state N2 - In Germany, spent fuel and heat generating radioactive waste is stored in casks for transport and storage (DPCs). The storage licenses were granted for up to 40 years. Due to the delay in identifying a final repository site for such radioactive waste, the storage periods are to be extended significantly. The objective of our research work is to collect additional material data for metal seals in order to be able to better assess the long-term safety of the sealing system of the casks for a period of up to 100 years. A principal safety consideration for the DPCs is the long-term performance of bolted lid sealing systems utilizing metal seals to ensure the safe enclosure of the radioactive inventory during interim storage. To assess the sealing behavior, it is necessary to examine the aging-dependent residual restoring force for the metal seals and the usable resilience. By investigating the change in these values as a function of time and temperature, further insight can be gained into the assessment of long-term safety for extended interim storage. In the present study, the restoring force of metal seals with an outer aluminum jacket and a torus diameter of 9.9 mm was measured continuously. For this purpose, a specially designed device equipped with a load cell was used under isothermal conditions. As part of the investigation, the level and rate of decrease of the restoring seal force were recorded over test periods of one and two months. The seal temperature was set to 35 °C, 75 °C, 100 °C, 125 °C, and 150 °C, respectively. A direct correlation was observed between the temperature of the seal, the level of the restoring force after compressing and heating the seal, and the drop-off characteristics of the restoring force. It was found that in our test device the force level immediately after reaching the respective temperature is lower for higher seal temperatures, while the drop rate of the restoring force is higher. This paper describes the experimental setting and discusses first results in comparison with our long-term discontinuous measurements. T2 - 21st International Symposium on the Packaging and Transportation of Radioactive Materials - PATRAM 2025 CY - San Antonio, TX, USA DA - 27.07.2025 KW - Temperature-Dependent Performance KW - Extended Interim Storage KW - Long-Term Safety Assessment KW - Metal Seal Aging KW - Restoring Force Degradation PY - 2025 AN - OPUS4-63891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert T1 - Systems With Cryogenic Liquefied Gases In Fire-Incidents N2 - The volumetric energy density of a gas can be increased by liquefaction, which occurs when the gas is cooled below the saturation point. Liquefied gases of great importance to the energy transition are Liquefied Hydrogen (LH2) and Liquefied Natural Gas (LNG), which can be liquefied at temperatures below 160°C. Systems for storing these gases typically must be overpressure resistant and require thermal super insulations (TSI) to hold cryogenic conditions and minimize boil-off losses from evaporation. TSI with vacuum and MLI or perlites are suitable for many applications involving LNG and LH2. Such systems are typically double-walled structures where the inner wall is in contact with the cryogenic liquefied gas. MLI or perlites are located in the gap between the inner and the outer wall, that is kept under vacuum conditions. This combination of insulations strongly reduces the heat transfer between the environment and the cryogenic liquefied gas. From an economic point of view the systems are well sophisticated. However, knowledge of the behavior of this kind of systems in a typical event such as a fire is limited, but necessary to evaluate the safety of the increasing number of applications. The objective of the research is to determine how TSI behaves at different fire temperatures during fire exposure and afterwards. Special attention is paid to changes in the heat flux, the material properties and vacuum state over time. For this purpose, thermogravimetric analysis (TGA) studies have been carried out. In addition, a test rig was developed that allows testing of TSI at temperatures up to 1000°C under realistic integration conditions and subsequent analysis of the TSI samples. In the test rig the double-wall with vacuum and MLI or perlites inside is simulated. The fire conditions are simulated on one side of the double-wall by adjustable electrical heating elements. This process allows the implementation of repeatable heat flows of up to 100 kW/m². On the other side of the double-wall, cold or cryogenic conditions are simulated with a heat exchanger through which water or the vapor of liquid nitrogen (approx. -196°C) flows. The heat exchanger is also used to determine the heat flux through the double-wall. Thus, the test rig allows thermal loading and performance analysis of TSI samples at the same time. Compared to tests with real cryogenic systems, tests with this experimental setup have the advantage that, first, the instrumentation is easier to realize, and a higher repeatability is ensured. Second, the local heat flow can be determined over time, and the sample of a TSI can be taken non-destructively and thus analyzed. Third, the tests are less risky as well as time+ and material intensive, so that more tests and variants can be investigated with the same budget. Preliminary results obtained considering several types of MLI under vacuum show that all observed typs of MLI can be damaged under strong thermal loading. The damages observed were outgassing, melting, shrinkage, cracking, lump formation, and concomitant local loss of the MLI's function as a radiation shield. However, the study also shows that a damage does not always have an extreme effect on the insulating performance. T2 - IMECE2022 CY - Columbus, Ohio, USA DA - 30.10.2022 KW - LH2 KW - LNG KW - Safety KW - Insulation KW - Tank PY - 2022 AN - OPUS4-56445 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bayat, Mehmet A1 - Kipphardt, Heinrich A1 - Tiebe, Carlo A1 - Engelhard, Carsten T1 - Effect of Trace Humidity on Trace Ammonia Quantification N2 - Hydrogen is receiving growing attention as a promising medium for energy storage and transportation. Proton exchange membrane (PEM) fuel cells are a key technology for energy conversion from hydrogen. However, high purity hydrogen is required for this technology, as described in standards such as ISO 14687:2019. A critical impurity that impairs PEM efficiency is ammonia, for which a limit value of 100 nmol/mol applies. In addition, the maximum amount of humidity is specified with 5 µmol/mol. The presence of humidity in hydrogen at levels up to 50 times higher than ammonia raises the critical question of whether ammonia can still be quantified accurately in the lower nmol/mol range without interference from water. In addition, the general question arises as to whether the critical analyte, ammonia, can still be detected at all, given the expected surface effects at such amounts of trace humidity. In this work, we describe the influence of trace humidity on the surface behavior of adsorbed ammonia on stainless steel. Samples with ammonia at approximately 100 nmol/mol in hydrogen, with trace humidity levels ranging from 3 µmol/mol to 10 µmol/mol, were carefully prepared using dynamic mixing. Humidification was conducted using an advanced saturation method. These samples were investigated under atmospheric conditions using low pressure sampling Optical Feedback Cavity Enhanced Absorption Spectroscopy (OFCEAS). From the observed time-dependent signals, kinetics were determined and analyzed, yielding insights on the strength of the adsorption behavior of the analytes. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - OF-CEAS KW - Hydrogen KW - Ammonia KW - Water KW - Humidity KW - Kinetics KW - Adsorption PY - 2025 UR - https://veranstaltungen.gdch.de/microsite/index.cfm?l=11713&sp_id=2&selSiteID=vplanner AN - OPUS4-64046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Morcillo, Dalia T1 - Study of Age-Induced Isotope Fractionation in Lithium-ion Batteries using Microwave-Induced Cold Nitrogen Plasma Mass Spectrometry N2 - This study investigates the use of a microwave-induced cold nitrogen plasma ionization source, coupled with a single quadrupole mass analyzer, as a cost-effective alternative to multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for analyzing lithium isotopic composition in lithium-ion batteries. The performance of both instruments was compared in measuring δ7Li values vs an isotopic standard in new and aged commercial lithium cobalt oxide (LCO) batteries. Results indicate that the microwave-induced ionization source, operating under cold plasma conditions at 800 W with an 8 mm torch depth position, achieves precision comparable to MC-ICP-MS, with δ7Li values ranging from 0.7 ‰ to 3.4 ‰. This method benefits from a dielectric resonator for uniform plasma, better ion velocity control, and higher energy efficiency [1-3]. Optimal settings were established as dwell times of 10 ms for 6Li and 1 ms for 7Li. The study found that 6Li migrates to the anode during multiple charge/discharge cycles, leading to the accumulation of 7Li at the cathode. This fractionation effect becomes more visible with repeated cycling. The microwave-induced ionization source offers a cost-effective and accurate alternative to MC-ICP-MS, with increased portability, facilitating further research into isotopic fractionation and aging of lithium-ion batteries. T2 - Adlershofer Forschungsforum 2024 CY - Berlin, Germany DA - 11.11.2024 KW - Cold nitrogen plasma KW - Lithium isotope KW - Battery PY - 2024 AN - OPUS4-62024 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winckelmann, Alexander T1 - Investigation of degradation of the aluminum current collector in lithium-ion batteries by glow-discharge optical emission spectroscopy N2 - Lithium-ion batteries (LIBs) are one technology to overcome the challenges of climate and energy crisis. They are widely used in electric vehicles, consumer electronics, or as storage for renewable energy sources. However, despite innovations in batteries' components like cathode and anode materials, separators, and electrolytes, the aging mechanism related to metallic aluminum current collector degradation causes a significant drop in their performance and prevents the durable use of LIBs. Glow-discharge optical emission spectroscopy (GD-OES) is a powerful method for depth-profiling of batteries' electrode materials. This work investigates aging-induced aluminum deposition on commercial lithium cobalt oxide (LCO) batteries' cathodes. The results illustrate the depth-resolved elemental distribution from the cathode surface to the current collector. An accumulation of aluminum is found on the cathode surface by GD-OES, consistent with results from energy-dispersive X-ray spectroscopy (EDX) combined with focused ion beam (FIB) cutting. In comparison to FIB-EDX, GD-OES allows a fast and manageable depth-profiling. Results from different positions on an aged cathode indicate an inhomogeneous aluminum film growth on the surface. The conclusions from these experiments can lead to a better understanding of the degradation of the aluminum current collector, thus leading to higher lifetimes of LIBs. T2 - Adlershofer Forschungsforum 2022 CY - Berlin, Germany DA - 11.11.2022 KW - Lithium Ion Batteries KW - GD-OES KW - FIB KW - SEM KW - EDX PY - 2022 AN - OPUS4-56246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winckelmann, Alexander T1 - Investigation of degradation of the aluminum current collector in lithium-ion batteries by glow-discharge optical emission spectroscopy N2 - Lithium-ion batteries (LIBs) are one technology to overcome the challenges of climate and energy crisis. They are widely used in electric vehicles, consumer electronics, or as storage for renewable energy sources. However, despite innovations in batteries' components like cathode and anode materials, separators, and electrolytes, the aging mechanism related to metallic aluminum current collector degradation causes a significant drop in their performance and prevents the durable use of LIBs.[1] Glow-discharge optical emission spectroscopy (GD-OES) is a powerful method for depth-profiling of batteries' electrode materials. This work investigates aging-induced aluminum deposition on commercial lithium cobalt oxide (LCO) batteries' cathodes. The results illustrate the depth-resolved elemental distribution from the cathode surface to the current collector. An accumulation of aluminum is found on the cathode surface by GD-OES, consistent with results from energy-dispersive X-ray spectroscopy (EDX) combined with focused ion beam (FIB) cutting. In comparison to FIB-EDX, GD-OES allows a fast and manageable depth-profiling. Results from different positions on an aged cathode indicate an inhomogeneous aluminum film growth on the surface. The conclusions from these experiments can lead to a better understanding of the degradation of the aluminum current collector, thus leading to higher lifetimes of LIBs. T2 - European Winter Conference on Plasma Spectrochemistry (EWCPS 2023) CY - Ljubljana, Slovenia DA - 29.01.2023 KW - Lithium-ion batteries KW - Aging mechanisms KW - Depth-profiling PY - 2023 AN - OPUS4-56992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael T1 - Hydrogen in Welded Microstructures of T24 Steel: Effect on Mechanical Properties and Corresponding Hydrogen Diffusion N2 - Low-alloyed CrMoV steels, such as T24, are widely used for welded components in fossil power stations due to their excellent creep-strength. Spectacular failure cases in the recent years exhibited severe cracking in T24 welds. The results showed that hydrogen-assisted cracking (HAC) occurring up to 200 degree Celsius cannot be excluded. Hence, a basic understanding is necessary on how hydrogen affects the material properties of welded microstructures. In this regard, each weld microstructure (HAZ and weld metal) has influence on the HAC susceptibility and respective hydrogen diffusion. Thus, the present contribution summarizes different results obtained from experiments with grades T24 (CrMoV alloy) and T22 (CrMo) and thermally simulated HAZ. Tensile tests were conducted with hydrogen charged specimens and compared to hydrogen-assisted stress corrosion cracking results obtained from slow strain rate tests (SSRT) up to 200 degree Celsius. Electrochemical permeation and degassing experiments were performed to identify a particular weld microstructure influence on hydrogen diffusion and trapping (especially in the HAZ). The results showed that T24 base material has improved resistance to hydrogen-assisted degradation/cracking. In contrast, the as-welded HAZ had remarkably increased susceptibility (tesnile tests at hydrogen concentration of 1 to 2 ppm). SSRT experiments confirmed this at elevated temperatures for both the T24 and the T22. Hence, the evaluation of a particular degradation of the mechanical properties should be performed independently for each weld microstructure. In addition, the HAZ showed decreased diffusion coefficients (at room temperature) of approximately one magnitude compared to the base materials. Trapped hydrogen was determined in the T24 at temperatures up to 120 degree Celsius compared to 75 degree Celsius in the T22. This has to be considered in case of changing operational temperatures, e.g. in the case of start-up and shutdown processes of boiler components. T2 - 10th Conference on Trends in Welding Research CY - Tokyo, Japan DA - 11.10.2016 KW - Degradation of Mechanical Properties KW - Hydrogen KW - Creep-resistant Steel KW - Weld Joint KW - Diffusion PY - 2016 AN - OPUS4-37827 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grimault de Freitas, Tomás T1 - Hollow Specimen Method for Tests in High-Pressure Hydrogen Gas: The TransHyDE - H2HohlZug Project N2 - As the world moves towards a decarbonised economy, the demand for sustainable and low-carbon alternatives is growing rapidly. Hydrogen has an important role to play in this transition, but in order to make the most of hydrogen as an energy carrier, a comprehensive understanding of its impact on the integrity of structural materials is necessary. Metallic materials, mainly steels, are the most commonly used structural materials in various components throughout the hydrogen supply chain. Ensuring their sustainable and safe use in hydrogen technologies is a crucial factor in the development of the hydrogen economy. This is particularly important since hydrogen can promote crack formation and ultimately lead to premature failure in these materials when combined with mechanical load. This process is commonly known as Hydrogen Embrittlement and can occur in almost all the steels used for the hydrogen technologies. Extensive materials qualification is required for the rapid implementation of hydrogen technologies, however, most accepted, and standardised test methods for determining the effect of gaseous hydrogen on metallic materials describe complex and costly procedures that are only available to a very limited extent worldwide. The hollow specimen technique is a simple and economical method that has the potential to overcome the limitations of the current methods and complement them for qualifying metallic materials under high-pressure hydrogen gas. Unlike the conventional autoclave technique, this method requires significantly lower amounts of hydrogen, resulting in fewer safety measures and no need for complex equipment or a specialised laboratory. The technique's low investment and testing costs, simple operation, and shorter testing time make it an optimal for widespread use around the world, thereby increasing the output of results. Initial studies have demonstrated the feasibility of assessing hydrogen effects in metallic materials using the hollow specimen technique. This led to the establishment of an ISO committee to standardise the method. However, there are open questions that currently prevent the technique from being standardised for hydrogen testing. These open questions relate to specimen geometry, inner hole surface and gas quality and are being addressed in the H2HohlZug project, of which the overall aim is to systematically close the gaps towards a standard. This contribution presents the structure and milestones of the project, followed by initial results. T2 - TransHyDE Vollversammlung 2025 CY - Leipzig, Germany DA - 26.11.2025 KW - Hydrogen KW - Hydrogen Embrittlement KW - Hollow Specimen Technique KW - High-Pressure Gaseous Hydrogen KW - TransHyDE KW - H2HohlZug KW - Standardisation PY - 2025 AN - OPUS4-64938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - El Harrab, Hayat A1 - Askar, Enis A1 - Franken, T. A1 - Mauss, F. T1 - Experimental and Kinetic Study of Lubrication Oil Composition on Hydrogen Auto-Ignition N2 - Hydrogen internal combustion engines (H₂ ICEs) present a promising alternative to conventional fuels, but they face challenges such as pre-ignition, where lubricating oils play a critical role. This study investigates the auto-ignition behavior of two base oils — Group II (mineral) and Group V (Ester) — and three formulated oils (Oils A, B, and C) at 20 bar using a heated constant-volume autoclave. Oil A and Oil B share a Group II (mineral) base, with Oil A containing lower levels of calcium-based detergents and higher levels of phosphorus-based antioxidants compared to Oil B. In contrast, Oil C is formulated with a Group V (ester) base oil, incorporating magnesium-calcium detergents. The auto-ignition temperature was measured in both air and stoichiometric hydrogen-air mixtures to assess the influence of oil composition, additives, and hydrogen addition on ignition characteristics. Results show that hydrogen’s AIT at 20 bar is 460°C but drops to 270°C with the addition of 0.2 ml of base oil. Base oils exhibited similar AITs in air (260°C) and hydrogen-air mixtures (270°C), with reactivity differences linked to molecular composition — ester (Group V) displayed lower reactivity compared to mineral oil (Group II). Formulated oils demonstrated slightly higher AITs (up to 290°C), where phosphorus-based additives reduced reactivity, while lower calcium content further slowed ignition. Among the tested oils, the ester-based oil with a mixture of calcium and magnesium detergents exhibited the lowest reactivity, making it a promising candidate for hydrogen engines. Additionally, reduced oxygen availability increased AIT by 10°C and prolonged ignition delay. A chemical analysis was also performed to evaluate the ignition properties of Group II (mineral) and Group V (ester) oils under varying temperatures. These findings highlight the impact of lubricant composition on pre-ignition behavior in H₂ ICEs, offering valuable insights for optimizing lubricant formulations. T2 - 12th European Combustion Meeting CY - Edinburgh, United Kingdom DA - 07.04.2025 KW - Hydrogen KW - Pre-Ignition KW - Group V Ester Oil KW - Auto-Ignition Temperature KW - Additive Effects KW - Ignition Delay Time KW - Group II Mineral Oil KW - Lubricating Oil PY - 2025 AN - OPUS4-64761 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Konert, Florian T1 - Evaluation of hydrogen effect on hardened and annealed 100Cr6 steel N2 - The use of hydrogen demands high safety requirements, since hydrogen can be absorbed by metallic materials and may cause hydrogen embrittlement (HE) under certain conditions. Slow strain rate (SSR) tensile testing is a widespread method to quantify the hydrogen-induced ductility loss of alloys. Here, the hollow specimen technique was used to evaluate the effect of 150 bar hydrogen on the tensile properties of solution annealed and hardened 100Cr6 steel, which is a common material for bearing systems. This technique reduces the required amount of hydrogen and minimizes the duration and costs of the tests performed compared to in-situ tensile tests in autoclaves. T2 - EPRI Workshop on Hydrogen Embrittlement 2024 CY - Oxford, UK DA - 23.06.2024 KW - Hydrogen KW - Hydrogen Embrittlement KW - Hollow Specimen Technique KW - 100Cr6 PY - 2024 AN - OPUS4-60476 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nietzke, Jonathan T1 - Influence of strain rate on the effect of hydrogen in pre-charged 316L stainless steel: A comparison of conventional and hollow specimen testing N2 - The growing demand for hydrogen requires an expansion of testing capabilities to assess the performance of metallic materials under hydrogen exposure. Considering only gaseous atmospheres, there is a variety of in-situ and ex-situ methods used to investigate the material behavior while or after exposed to hydrogen, respectively. Among these methods, a more conservative one is the in-situ testing at slow strain rates (SSRT) using conventional tensile specimens. While results obtained by a conservative procedure may be more applicable in many cases than those of ex-situ experiments, the tests are quite demanding, leading to limited testing capacities and high costs, especially for very slow strain rates. A possible solution that can enable in-situ testing at relatively low cost is the hollow specimen technique which gained increasing interest in the last decade. The main reasons are the minimal volume of hydrogen required and the elimination of a high-pressure hydrogen autoclave leading to significantly lower costs and enabling more laboratories worldwide to perform these tests. However, interpreting results from hollow specimens, especially when compared to conventional ones, remains a significant challenge. To address this, an experimental study was conducted using conventional and hollow specimens, both uncharged and pre-charged. Pre-charging was achieved using pure hydrogen (5.0, i.e. 99.999 %) at 100 bar and 300 °C for around 21 days. In order to obtain suitable reference specimens, other specimens were stored in argon at 100 bar and 300 °C for the same period of time. The tests were performed at various strain rates, down to 1E-6 1/s. While these ex-situ experiments are not directly comparable to in-situ tests with both types of specimens, they do provide some insights into the differences between the results of hollow and conventional specimens. Therefore, the elongation at fracture and reduction of area (RA) were compared, among other aspects. In addition, fractographical analyses were carried out using SEM images. Elongation at fracture was not significantly affected by hydrogen in conventional specimens, but it was slightly reduced in hollow specimens. RA, on the other hand, was lower for tests with hydrogen in both types of specimens across all strain rates. Moreover, the strain rate did not appear to influence hydrogen embrittlement in conventional specimens whereas in hollow specimens, tests conducted at higher strain rates (1E-4 1/s) showed a greater impact of hydrogen on elongation at fracture than those at lower strain rates (1E-6 1/s), which is contrary to the typical expectation. These findings suggest that the influence of hydrogen differs between conventional and hollow specimens, possibly due to factors such as surface roughness and differing stress states. However, further experiments are needed to fully understand these differences, including in-situ experiments to understand potential differences in hydrogen absorption between the two specimen types. T2 - EPRI Workshop on Hydrogen Embrittlement CY - Oxford, England, United Kingdom DA - 23.06.2024 KW - Stainless steel KW - Hollow specimen KW - Pre-charging KW - Hydrogen PY - 2024 AN - OPUS4-60494 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mosquera Feijoo, Maria T1 - Thermal-mechanical fatigue of oxide scales in cyclic water vapor oxidation of 9-12 % Cr steels N2 - Ferritic-martensitic steels with 9-12 % Cr-content are widely used as high temperature construction materials in power plant due to their high temperature properties such as creep resistance, strength, and favorable oxidation resistances. However, typical operating conditions include cyclic thermal/mechanical loading, and as a result the oxide scale might fail; cracks are formed and the oxide scale is spalled off. The oxide spalls can cause steam tube blocking and local thermal stresses, which might provoke shorter component service life. This work investigates the scale spallation behavior of ferritic-martensitic steels under cyclic load condition between 320°C and 620°C for up to 210 cycles in pure steam. All samples were isothermally pre-oxidized at 620°C for 500 h in water steam with 30 bar pressure to create an initial magnetite layer with low porosity. Different sample shapes, rectangular coupons, full rings and U-shape segments, are investigated to evaluate the impact of the geometry on these conditions. After oxidation experiments the oxidation kinetics in terms of mass change, metal loss and thickness scale is determined. In addition, the integrity of the oxide layer as well as its adherence to the matrix are characterized by modified hardness tests and scratch tests. Breakage of the layers at lower applied forces indicates a substantial loss of adhesion strength at intermediate cycle numbers. T2 - EUROCORR 2017 CY - Prague, Czech-Republic DA - 03.09.2017 KW - Geometry influence KW - Therma-mechanical fatigue KW - Oxide layer KW - Cyclic test KW - Scale adherence PY - 2017 AN - OPUS4-42635 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Leo, Reinhold T1 - Duplex stainless steels - Compatibility for high-pressure hydrogen applications N2 - Duplex Stainless Steels (DSS) are an essential component used in the construction of transportation pipelines because of their many distinctive qualities. The choice of DSS for a particular hydrogen application mainly depends on its susceptibility level to Hydrogen Assisted Cracking (HAC). Several mechanisms have been proposed to describe the occurring microscale processes behind HAC, and these include metastable phase transformation, Hydrogen Enhanced Localized Plasticity (HELP), and Hydrogen Enhanced Decohesion (HEDE). This contribution describes the path to ascertain if DSS is suitable for high-pressure gaseous hydrogen applications. The interplay between several critical factors that result in HAC was examined using high-pressure gaseous hydrogen charging, Electron Backscatter Diffraction (EBSD), tensile testing and hydrogen concentration measurements using Carrier Gas Hot Extraction (CGHE). T2 - Third German-African Green Hydrogen Forum 2025 CY - Bernburg (Saale), Germany DA - 23.09.2025 KW - Hydrogen Assisted Cracking KW - High Pressure Hydrogen KW - Duplex Stainless Steels KW - Hollow Specimen Technique PY - 2025 AN - OPUS4-64302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mayer, Uwe T1 - Untersuchung des Master Curve-Konzeptes für ferritisches Gusseisen mit Kugelgraphit N2 - In dem Poster werden der Forschungsansatz, die Ziele, das Untersuchungsprogramm und die erwarteten Ergebnisse des BMUV-Forschungsvorhabens MCGUSS "Untersuchung des Master Curve-Konzeptes für ferritisches Gusseisen mit Kugelgraphit" vorgestellt. Mit Blick auf bruchmechanische Sicherheitsbewertungen in der Kerntechnik werden Stähle momentan mit dem deterministischen ASME-Referenzkurvenkonzept, ergänzt durch das probabilistische Master Curve-Konzept nach ASTM E1921, bewertet. Das Master Curve-Konzept wird bereits für die Bewertung von ferritischen Schmiedestahlbehältern verwendet. Bewertungsmethoden für ferritisches Gusseisen mit Kugelgraphit sind im Moment unvollständig. Normen wie die nationale BDG-Richtlinie P300 oder der internationale ASME-Code, Sect. III, Div. 3, WC-2330 decken Sprödbruch nicht ausreichend ab. Die Verwendung des Master Curve-Konzepts für ferritisches Gusseisen mit Kugelgraphit würde eine bruchmechanische Bewertung via einer KJc,d Verteilung erlauben und gleichzeitig Größeneffekte und einen Temperaturbereich von 100 K berücksichtigen. T2 - GRS-Projektstatusgespräch 2023 CY - Karlsruhe, Germany DA - 06.11.2023 KW - Dynamische Bruchzähigkeit KW - Sprödbruch KW - Gusseisen mit Kugelgraphit KW - Master Curve PY - 2023 AN - OPUS4-59060 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Butz, Adam T1 - Experimental and analytical investigation of notched components of a Nickel based superalloy under high temperature cyclic loading N2 - While the increase in use of renewable energy sources is a necessity in times of climate change the use of gas turbines as back-up requires them to be run in a much more flexible manner in order to compensate for side effects like sudden fluctuations of energy generation. The significant changes of stress and temperature levels in turbine blades due to start-up and shut down can cause crack initiation and growth in the blades‘ alloy. The aim of this research project is to identify a model for lifetime prediction for gas turbine components made of a Nickel base superalloy under high temperature with a Focus on stress concentration points such as cooling holes. T2 - HIDA-7 Conference on Life/Crack Assessment & Failures in Industrial Structures, UK CY - Portsmouth, UK DA - 15.05.2017 KW - LCF KW - Gas turbine KW - Service life model PY - 2017 AN - OPUS4-42274 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mesquita Silva da Veiga, Marcia T1 - Ultrasonic-assisted leaching of Li and Co from black mass using deep eutectic solvent N2 - The recovery of critical metals from spent lithium-ion batteries is a key strategy for sustainable resource management and the circular economy. Conventional hydrometallurgical processes typically rely on strong mineral acids and elevated temperatures, which, although effective, generate hazardous waste and demand high energy inputs. As a greener alternative, deep eutectic solvents (DES) combine low toxicity, non-volatility, simple synthesis, and tunable physicochemical properties, making them promising media for selective metal recovery1-2. Here, we report for the first time the use of ultrasound (US) to assist the leaching of Li and Co from LiCoO₂ black mass employing a deep eutectic solvent based on choline chloride and formic acid (ChCl:HCOOH, 1:2 molar ratio). The DES was synthesized at 90 °C for 3 h under stirring (300 rpm) and was characterized in terms of its molecular structure and formation by 1H-NMR and FT-IR, as well as by its viscosity and density. For each experiment, ~0.100 g of LiCoO2 was treated with 5 g of DES-FA in an ultrasonic bath (35 kHz, 60 °C) for different irradiation times (30–120 min), followed by three sequential extractions. All measurements were performed by ICP OES. Lithium solubilization reached ~80% at 90 min, while cobalt extraction was stabilizing at ~79% after 120 min. The enhanced performance under US is attributed to sonochemical effects that promote cavitation and microjets, leading to the disruption of particle agglomerates, the thinning of diffusion layers, and the generation of highly reactive local environments. These processes accelerate deintercalation and mass transfer within the solid–liquid interface. Combined with the mild acidity of DES-FA, which enables simultaneous leaching of both metals while favoring faster kinetics for Li, ultrasound provided a synergistic effect that enhanced the overall process and preserved the distinct extraction profiles of Li and Co. The extraction behavior of the two metals can be explained by their different speciation in the DES-FA medium. Cobalt is likely reduced from Co(III) to Co(II) by formic acid and stabilized through the formation of chloro-complexes such as [CoCl4]2- with chloride anions from ChCl, favoring its solubilization. In contrast, lithium does not form stable complexes with chloride under these conditions. It is primarily extracted as a solvated cation, stabilized by the extensive hydrogen-bond network of the DES. This difference accounts for the faster leaching kinetics observed for Li compared to Co. Selective recovery was achieved by pHcontrolled precipitation, with cobalt oxalate at pH 4-5 and lithium carbonate at pH 10. The Eco-Scale score of 85 confirmed the greenness of the method. This pioneering approach highlights the potential of coupling DES chemistry with ultrasound. Together, they represent a sustainable and efficient route for recovering critical metals from battery waste. T2 - 17th Rio Symposium on Atomic Spectrometry (17th RSAS) CY - São Pedro City, Brazil DA - 09.11.2025 KW - Black mass KW - deep eutectic solvent KW - Lithium KW - Cobalt KW - Lithium-ion battery recycling KW - Ultrasound-assisted extraction KW - Lithium and cobalt recovery KW - Green hydrometallurgy PY - 2025 AN - OPUS4-64956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grimault de Freitas, Tomás T1 - Comprehensive Standardisation of the Hollow Specimen Technique for Tests in High-Pressure Hydrogen Gas N2 - The hollow specimen technique is a simple and economical method that has the potential to overcome the limitations and complement the current techniques for qualifying metallic materials under highpressure hydrogen gas. In this technique, an axial hole is manufactured in a tensile specimen, which is then filled with hydrogen gas, sealed, and placed in a standard testing machine. This method requires significantly lower amounts of hydrogen, resulting in fewer safety measures and does not require complex equipment or a specialised laboratory, unlike the conventional autoclave technique. Initial studies have demonstrated the feasibility of assessing hydrogen effects in metallic materials using the hollow specimen technique. This led to the establishment of the committee ISO/TC 164/SC 1/WG 9 to standardise the method, however, there are still open questions that currently prevent the technique from being standardised for hydrogen testing. These open questions are being addressed in the H2HohlZug project, which is presented in this contribution. T2 - Oxford - EPRI Hydrogen Embrittlement Workshop CY - Oxford, United Kingdom DA - 23.06.2024 KW - Hollow Specimen Technique KW - High-pressure Gaseous Hydrogen KW - Hydrogen Embrittlement KW - Tensile Testing PY - 2024 AN - OPUS4-60501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Junias, Josua Kondja T1 - Prediction of Explosion Characteristics of Hydrogen Mixtures Using Machine Learning Models N2 - An understanding of Hydrogen-Oxygen/Air-Diluents gas mixtures combustion characteristics and their accurate prediction is crucial for ensuring the safety of hydrogen-related applications, reducing accidents risk, and protecting lives and property. Hydrogen detonation propagations are characterized by the detonation cell size, used to quantitatively predict for a mixture to detonate including, among others, the initiation energy, critical and minimum tube diameters. For the prediction of explosion limits, detonation run-up-distances and cell sizes, various empirical, semi-empirical and numerical models can be found in literature. These models are usually limited to a narrow range of explosion process or geometrical experimental parameters. Moreover, based on the limited availability of the detonation cell widths measurements, current estimation models are seemingly inaccurate. Machine learning models can be utilized to make justifiable prediction on the detonation cell sizes of hydrogen-air mixtures and other gaseous explosive mixtures cell sizes, explosion limits or run-up distance to detonation based on the mixture type, temperature, pressure, equivalence ratios as well as on geometrical parameters with consideration of highly diverse experimental data measurements uncertainties. Therefore, an up-to date database for explosion characteristics will be established and machine learning models will be developed, trained, tested, and validated using experimental data to predict explosion characteristics of hydrogen mixtures. The models predicted results will be validated against existing models. It will be tested whether machine learning models are able to predict the explosion characteristics of hydrogen mixtures with better accuracy and more comprehensively than conventional empirical and numerical models to be found in literature. T2 - Combustion Institute 40th International Symposium CY - Milano, Italy DA - 21.07. 2024 KW - Prediction, detonation KW - Machine Learning KW - Flammability limits PY - 2024 AN - OPUS4-60769 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nattuveettil, Keerthana A1 - Brunner, Nanine A1 - Tiebe, Carlo A1 - Melzer, Michael A1 - Johann, Sergej A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias T1 - Einsatz von Sensortechnologien an einer Wasserstofftankstelle als Beitrag zur digitalen Qualitätsinfrastruktur T1 - Use of sensor technologies at hydrogen test platform as a part of QI Digital N2 - Die Optimierung und Validierung des digitalen Wasserstofftankstellenmanagements mit Sensortechnologien ist das übergeordnete Ziel des Teilprojekts Digitale Qualitätsinfrastruktur mit Sensortechnologien (QIST) am Use Case H2, im Rahmen der digitalen Qualitätsinfrastruktur (QI digital[1]). Hierfür sollen u.a. Sensornetzwerke mit digital-gestützten Auswertungsstrategien intelligent gestaltet werden (Stichwort KI bzw. digitaler Zwilling). Verschiedene, sich ergänzende Sensoren, Systemkomponenten und KI-Methoden stehen als Bausteine intelligenter Sensorsysteme zur Verfügung, mit dem Zweck, die physikalischen und chemischen Parameter an und in Anlagen umfassend und effizient zu überwachen sowie Fehlfunktionen zuverlässig zu detektieren und zu interpretieren, Abbildung 1. Konkrete Arbeitsschritte sind, nach dem Aufbau der Versuchsplattform „Wasserstofftankstelle“, die Instrumentierung von Sensorik und deren digitale Integration in das Tankstellenmanagementsystem sowie die Validierung im Realbetrieb. Die somit erzielten Messergebisse sowie die Messunsicherheiten, Historien und Verfahren werden in digitaler Form aufbereitet, gespeichert und fortlaufend in die KI-basierte Datenauswertung einbezogen, inkl. der Anbindung an die metrologische Rückführungskette. Ziele sind: • Einführung eines neuen messtechnischen Ansatzes und eines digitalen Zwillings für den Anwendungsfall "Wasserstofftankstelle" auf Basis der H2-Sensorik sowie der Zustandsgrößen Druck und Temperatur • Qualitätssicherung durch Applikationen zuverlässiger Gassensorik, Manometer und Thermometer sowie KI-Methoden zur Prozesskontrolle und Detektion von Fehlfunktionen • Nutzung von digitalen Kalibrierscheinen (DCCs) insbesondere für die Messgröße Temperatur zur Realisierung der metrologischen Rückführung in einer digitalen Qualitätsinfrastruktur T2 - Sensorik für die Digitalisierung chemischer Produktionsanlagen CY - Frankfurt a. M., Germany DA - 13.06.2022 KW - QI Digital KW - H2Safety@BAM KW - Wasserstoff KW - Hydrogen KW - Sensorik KW - Digitalisierung KW - Digitalisation PY - 2022 AN - OPUS4-55399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine T1 - Effect of temperature on the friction behaviour of rubber materials in hydrogen N2 - Safety and reliability are the major challenges to face for the development and acceptance of hydrogen technology. It is therefore crucial to study deeply material compatibility, in particular for tribological components that are directly in contact with hydrogen. Some of the most critical parts are sealing components that face high risk of damage due variation of pressure, temperature and mechanical stress. In this study, the friction and wear behaviour of several rubber materials was evaluated in hydrogen environment at ambient and low temperature. Tests were performed against 316L disks in a reciprocation motion. Results reveal that the hydrogen affects the friction and wear behaviour of most materials. The friction mechanism is dominated by deformation for most rubber materials at ambient temperature while sliding occurs at low temperature due to the increased hardness of the rubbers. T2 - Polytrib 2024 CY - Portorož, Slovenia DA - 03.10.2024 KW - Reciprocating sliding KW - Rubber materials KW - Hydrogen KW - Low temperature PY - 2024 AN - OPUS4-62019 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert T1 - LH2 Tanks In Fire Incidents - The Cryogenic High Temperature Thermal Vacuum Chamber Enables In-Depth Insights N2 - Liquefied Hydrogen (LH2) and Liquefied Natural Gas (LNG) establish themselves as important energy carriers in the transport sector. Their storage requires tanks with thermal super-insulations to keep them at cryogenic conditions for a long time. These insulation systems have proven itself in various applications over a long time. However, these insulations are still new in land transportation, where accidents involving collisions, fires, and their combination are to be expected. This study summarizes the results of the ongoing research program in which insulations commonly used in industry were analysed through experimental and numerical studies under fire-like conditions. It was found that there are strong differences among the various insulation systems. Several safety concerns and research gaps exists for layered insulations, which are typically used in land transport. To further analyse these insulation systems, a new test concept called Cryogenic High Temperature Thermal Vacuum Chamber (CHTTVC) was developed and manufactured. This concept enables the testing of large insulation samples under industrial conditions and the consideration of cryogenic conditions relevant for the investigation of various phenomena. The results are important for the evaluation of accident scenarios, the improvement of thermal super-insulations, and the development of emergency measures. T2 - IMECE 2024 CY - Portland, OR, USA DA - 17.11.2024 KW - LH2 KW - LNG KW - Fire KW - Insulation KW - Safety PY - 2024 AN - OPUS4-61752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzwarth, Marcel A1 - Baer, Wolfram T1 - Investigation of the Master Curve Concept for Ferritic Ductile Cast Iron N2 - The current framework for safety assessment of ferritic ductile cast iron (DCI) containers for transport and storage of radioactive materials applies fracture mechanics principles. As established by the IAEA safety standard SSG 26, prevention of crack initiation is the governing criterion and no reliance in design should be placed on any predicted ductile tearing resistance. Similarly, the ASME-Code, Sect. III, Div. 3 explicitly deals with DCI and requires a safety proof for dynamic loading conditions. However, information given in the guidelines does not seem to be sufficient to appropriately perform such dynamic fracture mechanics safety assessments. The ongoing German research project MCGUSS is tailored to tackle this status. In MCGUSS, the application potential of the probabilistic fracture mechanics master curve (MC) concept according to ASTM E1921 is being systematically investigated and potential modifications specific for dynamic brittle fracture of DCI will be identified. While MCGUSS covers testing of a high number of SE(B)- and C(T)-type specimens, this poster focuses on preliminary C(T) results. The obtained data was statistically analyzed, and current results of MC analyses are discussed. Special emphasis of MCGUSS is on using optical and scanning electron microscopy to link microstructural damage and failure processes to the fracture toughness data gained. A fracture mechanism called "specimen size-dependent arrest of local brittle fractures before global brittle failure by weakest link" is proposed to describe the established dynamic toughness data. Concerning the MC concept, it was shown that the ASTM E1921 procedure cannot simply be adopted to dynamic DCI toughness data on a one-to-one basis. Material specific modifications are being investigated and the DCI dynamic fracture toughness data base is to be expanded. T2 - MPA Conference 2025 CY - Stuttgart, Germany DA - 06.10.2025 KW - Dynamic fracture toughness KW - Ductile cast iron KW - Safety assessment KW - Master curve KW - Statistics PY - 2025 AN - OPUS4-64367 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sander, Luise T1 - Linking material and electrode properties to the cell performance of commercially available sodium-ion cells N2 - As the first commercial sodium-ion-batteries (SIBs) are available for purchase, it is possible to investigate material composition. Gaining an insight into the material composition of these SIBs is of interest not only for the classification of possible safety risks and hazards, but also in regard to recycling. Herein we report the preliminary investigations of the chemical and structural composition of first commercial SIB-cells.[1,2] Two different SIB-cell types were compared in terms of electrode size, thickness, loading etc. Furthermore, the composition of the active materials and electrolyte was investigated and compared. Finally, the gained results were linked to the different data sheet performance of the two cell types. T2 - Batterieforum Deutschland 2026 CY - Berlin, Germany DA - 20.01.2026 KW - Electrochemical Energy Storage KW - Battery KW - Sodium-ion-battery KW - EES KW - Energy Storage PY - 2026 AN - OPUS4-65588 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhattacharya, Biswajit A1 - Akhmetova, Irina A1 - Rautenberg, Max A1 - Emmerling, Franziska T1 - Mechanochemical synthesis of phosphonate-based proton conducting metal organic frameworks and hydrogen-bonded metal phosphonates N2 - Proton exchange membrane fuel cells (PEMFCs) are one of the most promising alternative green energy technologies that deliver high energy density without CO2 emissions. The proton conductivity of proton exchange membranes (PEM) contributes to the overall efficiency of a PEMFC. Materials being used as PEMs must exhibit high proton conductivity at the working conditions of the targeted PEMFC. To date, Nafion and Nafion-like polymers with acidic functionality are widely used as membrane materials due to their high proton conductivity in the range of 10-1 to 10-2 Scm-1 at higher relative humidity. However, these materials suffer from high costs, hazardous production process, and poor performance at high temperatures, limiting their versatility. In this context, crystalline porous materials are recognized as promising proton conductors for the proton exchange membrane (PEM) in fuel cell technology, owing to their tunable framework structure. However, it is still challenging bulk synthesis for real-world applications of these materials. Herein, we present mechanochemical gram-scale synthesis of series of mixed ligand metal organic frameworks (MOFs) and metal hydrogen‐bonded organic frameworks (MHOFs) using phenylene diphosphonic acid and 1-hydroxyethylidene-1,1-diphosphonic acid with different bipyridyl type of ligands, respectively. In all cases, the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, the frameworks exhibited high proton conductivity. The study demonstrates the potential of green mechanosynthesis for preparations of framework-based proton conducting materials in bulk scale for green energy generation. T2 - 4th International Conference on Phosphonate Chemistry, Science and Technology, ICOPHOS-4 CY - Crete, Greece DA - 02.10.2023 KW - Proton exchange membrane fuel cells KW - Metal organic frameworks KW - Proton conducting materials PY - 2023 AN - OPUS4-58837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietzmann, Simon T1 - Between Homogenous and Heterogenous Catalysis: Single-Atom-Catalysts N2 - Catalysis is a very important process in chemistry as it lowers the energy barrier for chemical reactions. This saves energy and/or some reactions are only possible with a catalyst under the desired conditions (temperature and pressure). Catalysts can be roughly categorized depending on the phase they interact with the substrates in homogenous and heterogenous catalysis. T2 - 5. Deutsche Tagung für Forschung mit Synchrotronstrahlung, Neutronen und Ionenstrahlen an Großgeräten (SNI2022) CY - Berlin, Germany DA - 05.09.2022 KW - Single-atom-catalyst KW - Electrochemistry KW - Porous carbons PY - 2022 AN - OPUS4-61989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietzmann, Simon T1 - Between Homogenous and Heterogenous Catalysis: Single-Atom-Catalysts N2 - Catalysis is a very important process in chemistry as it lowers the energy barrier for chemical reactions. This saves energy and/or some reactions are only possible with a catalyst under the desired conditions (temperature and pressure). Catalysts can be roughly categorized depending on the phase they interact with the substrates in heterougenous and heterogenous catalyst T2 - RÅC international summer school CY - Varberg, Sweden DA - 14.08.2022 KW - Single-atom-catalyst KW - Electrochemistry KW - Porous carbons PY - 2022 AN - OPUS4-61983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietzmann, Simon T1 - XAS for structural characterization of atomically dispersed materials N2 - metal and nitrogen enriched carbons (M-N-C) are promising electrocatalysts for small molecule activation. It is proposed that the nitrogen is forming a stabilizing N4-site for the catalytically active metal. This can be proven by XAS measurements to confirm the coordination sphere around the metal. T2 - Bessy User Meeting CY - Online meeting DA - 08.12.2024 KW - Single-atom-catalyst KW - Structural characterization KW - Porous carbons PY - 2022 AN - OPUS4-61994 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Shu-Han T1 - MOF-derived Synthetic Carbon Anode Materials for Sodium-Ion Batteries N2 - Metal-organic frameworks (MOFs), particularly the zeolitic imidazolate framework (ZIF) family, are attractive precursors for advanced energy-storage materials. Upon pyrolysis, ZIFs can be transformed into electrically conductive carbon materials while preserving their original particle morphology, which is crucial for achieving high-performance sodium-ion battery anodes. Despite these advantages, large-scale implementation remains challenging due to the need for synthesis routes that balance performance, cost, and sustainability. The present study addresses these challenges by developing environmentally benign and economically feasible strategies for the scalable production of ZIF-8-derived carbon anodes suitable for industrial applications. T2 - Batterieforum Deutschland 2026 CY - Berlin, Germany DA - 20.01.2026 KW - Sodium-ion battery KW - Negative electrode KW - Metalorganic frameworks PY - 2026 AN - OPUS4-65644 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Roy, Arkendu T1 - Hydroxide Based High Entropy MOF for Oxygen Evolution Reaction N2 - The energy crisis becomes more prominent in higher altitude countries like Germany, with higher annual energy demand. Thus, the generation of higher energy density fuel like hydrogen from renewable resources become the only way to solve the zero-emission energy system while avoiding the expensive batteries as an energy storage option. Therefore, water electrolysis cells to produce hydrogen and oxygen by storing of solar/wind energy in chemical bonds is a fruitful alternative for renewable and long-term energy generation. Thus, designing inexpensive water-splitting electrocatalyst material becomes a field of research of utmost importance. High entropy metal hydroxide organic frameworks (HE-MHOFs) are composed of high entropy hydroxide layer inside MOFs, resulting in a high degree of structural complexity and diversity than conventional MOFs. The concept of ‘high entropy’ refers to multiple types of metal ions (Metal = TM) in a near equimolar ratio in the same framework, creating a high degree of disorder and many possible structural configurations. Here, the HE-MHOF successfully synthesized by a conventional solvothermal process, crystallizes in the single phase with significant lattice distortion. A special-quasi-random (SQS) structure was simulated with equimolar compositions (~20% TM = Mn, Co, Ni, Cu and Zn) and a comparison was made with the ICP-AES (inductively coupled plasma atomic emission spectroscopy), XANES (X-ray absorption near edge structure) and XAFS (X-ray absorption fine structure) observations. Further, the elemental mapping (Energy dispersive Spectroscopy) of HE-MHOF shows the presence of all five different metals in the same crystallite to substantiate the ‘high entropy’ state of the MOF. The HE-MHOF offers improved thermal stability than mono-metallic MHOF and exhibit unique properties compared to traditional monometallic (Ni2+) MOF variants. Firstly, to elucidate the effect of the multimetallic system on the catalytic performance, we have performed density functional theory (DFT) calculations to investigate pre-redox cycles involved in the catalytic activation of HE (and Ni)-MOFs. HE-MHOF is further investigated as an electrocatalyst for oxygen evolution reaction (OER) due to its special high entropy hydroxide layered structure and electronic properties. Our DFT results have examined the traditional proton-coupled electron transfer (PCET) steps involving the single transition-metal site. The scrutiny of d-band centers and their behaviour in catalytic upgradation is investigated with density of states (DOS) analysis. It exhibits outstanding performance towards oxygen evolution reaction (OER) comparable to the experimental findings, which is also comparable to state-of-the-art OER catalysts based on precious metals such as iridium oxide and platinum carbon. We have considered different electrolyte solutions to elucidate the fast kinetics oxygen evolution reaction in the presence of various external nucleophilic anions. In hydroxyl-based MOFs, electrolytes' influence can substantially enhance catalytic activities. Here, with the help of DFT simulations, we have investigated the effect of the nucleophilicity of anion on each elementary reaction involved in the PCET mechanism of OER. T2 - EuroMOF 2023 CY - Granada, Spain DA - 24.09.2023 KW - Metal-organic Framework KW - High Entropy Materials KW - Electrocatalysis PY - 2023 AN - OPUS4-58971 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietzmann, Simon A1 - Mehmood, Asad A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska A1 - Fellinger, Tim-Patrick A1 - Thomas, A. T1 - Characterization of Solid-State Complexes by XAS N2 - Atomically dispersed metal-nitrogen doped carbons (M-N-C) are promising catalysts for the activation of small molecules such as O2 and CO2. These single atom catalysts (SAC) operate at the interface between homogenous and heterogenous catalysts. Currently, many examples of M-N-C are known with good oxygen reduction reaction activity but lacking a controlled synthesis of the specific active sites of the precatalyst. Recently, our group facilitated the synthesis of pure pyrrolic M-N4 sites using Zn ions as imprinters.[1] These amorphous materials obtained by active site imprinting method are characterized at the BAMline (Bessy II) by X-ray absorption spectroscopy (XAS). In-situ/operando measurements will be crucial in future work for a better understanding of the dynamic changes of the active site. T2 - InSynX Workshop 2023 CY - Sao Paulo, Brazil DA - 06.03.2023 KW - Solid-State Complexes PY - 2023 AN - OPUS4-58933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gugin, Nikita T1 - Large-Scale Synthesis of ZIF-8 for Hydrogen Storage: Batch and Continuous Modes N2 - We report the scale-up of a batch solid synthesis of zeolitic imidazolate framework-8 (ZIF-8) for reactive extrusion. The crystalline product forms in the extruder directly under the mixture of solid 2-methylimidazole and basic zinc carbonate in the presence of a catalytic amount of liquid. Highly crystalline ZIF-8 with a Brunauer−Emmett−Teller (BET) surface area of 1816 m2 g−1 was quantitatively prepared at mild temperature using a catalytic amount of ethanol and a small excess of the linker. Extruded ZIF-8 is an affordable alternative to commercial Basolite Z1200 as a reference material for H2 cryoadsorption. T2 - Metrology for Advanced Hydrogen Storage Solutions (MefHySto) Closing Conference CY - Berlin, Germany DA - 03.07.2023 KW - In situ Raman KW - Large-scale processing KW - Mechanochemistry KW - Twin-screw extrusion (TSE) PY - 2023 AN - OPUS4-58926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moss, Caitlin T1 - Framework Materials for the Electrocatalytic Reduction of Nitrate to Ammonia N2 - The electrocatalytic reduction of nitrate to ammonia offers a sustainable alternative to the energy-intensive Haber-Bosch process while simultaneously addressing the pressing issue of nitrate pollution in water sources. Developing efficient catalysts for this reaction is therefore vital for both environmental remediation and green ammonia production. Framework materials such as metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and coordination polymers present an emerging class of electrocatalytic materials due to their high surface area, tunable porosity, and structural modularity. Their ability to incorporate diverse metal centers and functional groups makes them promising candidates for selective and efficient nitrate reduction. In order to change and improve catalytic properties, different synthesis strategies can be pursued, such as metal alloying or calcination under different conditions. To fully understand and optimize these materials, advanced characterization techniques are essential to correlate structural features with catalytic performance, alongside in-situ methods for real-time mechanistic insights. T2 - Tag der Chemie 2025 CY - Berlin, Germany DA - 03.07.2025 KW - Electrocatalysis KW - Electrochemisty KW - Framework Materials KW - Ammonia Synthesis KW - Nitrate Reduction PY - 2025 AN - OPUS4-63815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmalz, Alina T1 - Framework Materials for the Electrocatalytic Reduction of Nitrate to Ammonia N2 - The electrocatalytic reduction of nitrate to ammonia offers a sustainable alternative to the energy-intensive Haber-Bosch process while simultaneously addressing the pressing issue of nitrate pollution in water sources. Developing efficient catalysts for this reaction is therefore vital for both environmental remediation and green ammonia production. Framework materials such as metal-organic frameworks (MOFs) or metalated covalent organic frameworks (COFs) present an emerging class of electrocatalytic materials due to their high surface area, tunable porosity, and structural modularity. Their ability to incorporate diverse metal centers and functional groups makes them promising candidates for selective and efficient nitrate reduction. In order to change and improve catalytic properties, different synthesis strategies can be pursued, such as metal alloying, doping or calcination. To fully understand and optimize these materials, advanced characterization techniques are essential to correlate structural features with catalytic performance, alongside in-situ methods for real-time mechanistic insights. T2 - 10th European Crystallography School CY - Ohrid, North Macedonia DA - 23.06.2025 KW - Electrocatalysis KW - Electrochemistry KW - Framework Materials KW - Ammonia Synthesis KW - Nitrate Reduction PY - 2025 AN - OPUS4-63846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hartwig, Peter T1 - Sichere Wasserstoffnetze ModuH2Pipe N2 - Modulare Testplattform für den sicheren Transport von Wasserstoff in neuen und vorhandenen Gasverteilnetzen Die BAM schafft mit der modularen Testplattform ModuH2Pipe erstmals in Europa eine Testinfrastruktur, welche die Betrachtung sicherheitstechnischer Fragestellungen im Realmaßstab und zugleich unter kritischen Bedingungen erlaubt, die sich im Zusammenhang mit Wasserstoff-und Wasserstoff-Erdgas-Pipelines stellen. Ziel ist, Gasnetzbetreibern u. a. ein Dienstleistungsangebot zur Verfügung zu stellen, welches die umfassende Beantwortung dieser und weiterer sicherheitstechnischer Fragestellungen ermöglicht. Die Testplattform ModuH2Pipe wird auf dem BAM Testgelände Technische Sicherheit (BAM TTS) stehen und integriert zwei Module, die für die experimentelle Untersuchung von Pipelinesegmenten, -komponenten (Dichtungen, Ventile etc.) und Polymerkomponenten im Originalmaßstab ausgelegt sind. Aber auch digitale Aspekte für Wasserstoffnetze können betrachtet werden. T2 - 1. Fachtagung für Anlagen- und Prozesstechnik CY - Berlin, Germany DA - 24.03.2026 KW - Wasserstoff KW - ModuH2Pipe KW - Testplattform KW - Realmaßstab KW - Wasserstoffkernnetz PY - 2026 AN - OPUS4-65765 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -