TY - JOUR A1 - Hendriks, L. A1 - Brunjes, R. A1 - Taskula, S. A1 - Kocic, J. A1 - Hattendorf, B. A1 - Bland, G. A1 - Lowry, G. A1 - Bolea-Fernandez, E. A1 - Vanhaecke, F. A1 - Wang, J. A1 - Baalousha, M. A1 - von der Au, Marcus A1 - Meermann, Björn A1 - Holbrook, T. A1 - Wagner, S. A1 - Harycki, S. A1 - Gundlach-Graham, A. A1 - von der Kammer, F. T1 - Results of an interlaboratory comparison for characterization of Pt nanoparticles using single-particle ICP-TOFMS N2 - This study describes an interlaboratory comparison (ILC) among nine (9) laboratories to evaluate and validate the standard operation procedure (SOP) for single-particle (sp) ICP-TOFMS developed within the context of the Horizon 2020 project ACEnano. The ILC was based on the characterization of two different Pt nanoparticle (NP) suspensions in terms of particle mass, particle number concentration, and isotopic composition. The two Pt NP suspensions were measured using icpTOF instruments (TOFWERK AG, Switzerland). Two Pt NP samples were characterized and mass equivalent spherical sizes (MESSs) of 40.4 ± 7 nm and 58.8 ± 8 nm were obtained, respectively. MESSs showed <16% relative standard deviation (RSD) among all participating labs and <4% RSD after exclusion of the two outliers. A good agreement was achieved between the different participating laboratories regarding particle mass, but the particle number concentration results were more scattered, with <53% RSD among all laboratories, which is consistent with results from previous ILC studies conducted using ICP-MS instrumentation equipped with a sequential mass spectrometer. Additionally, the capabilities of sp-ICP-TOFMS to determine masses on a particle basis are discussed with respect to the potential for particle density determination. Finally, because quasi-simultaneous multi-isotope and multielement determinations are a strength of ICP-TOFMS instrumentation, the precision and trueness of isotope ratio determinations were assessed. The average of 1000 measured particles yielded a precision of below ±1% for intensity ratios of the most abundant Pt isotopes, i.e. 194Pt and 195Pt, while the accuracy of isotope ratios with the lower abundant isotopes was limited by counting statistics. KW - ILC KW - spICP-MS KW - PtNP KW - Nanopartikel PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-580353 SN - 2040-3364 VL - 15 IS - 26 SP - 11268 EP - 11279 PB - Royal Society of Chemistry (RSC) AN - OPUS4-58035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bates, J. S. A1 - Martinez, J. J. A1 - Hall, M. N. A1 - Al-Omari, A. A. A1 - Murphy, E. A1 - Zeng, Y. A1 - Luo, F. A1 - Primbs, M. A1 - Menga, D. A1 - Bibent, N. A1 - Sougrati, M. T. A1 - Wagner, F. E. A1 - Atanassov, P. A1 - Wu, G. A1 - Strasser, P. A1 - Fellinger, Tim-Patrick A1 - Jaouen, F. A1 - Root, T. W. A1 - Stahl, S. S. T1 - Chemical Kinetic Method for Active-Site Quantification in Fe-N‑C Catalysts and Correlation with Molecular Probe and Spectroscopic Site-Counting Methods N2 - Mononuclear Fe ions ligated by nitrogen (FeNx) dispersed on nitrogen-doped carbon (Fe-N-C) serve as active centers for electrocatalytic O2 reduction and thermocatalytic aerobic oxidations. Despite their promise as replacements for precious metals in a variety of practical applications, such as fuel cells, the discovery of new Fe-N-C catalysts has relied primarily on empirical approaches. In this context, the development of quantitative structure−reactivity relationships and benchmarking of catalysts prepared by different synthetic routes and by different laboratories would be facilitated by the broader adoption of methods to quantify atomically dispersed FeNx active centers. In this study, we develop a kinetic probe reaction method that uses the aerobic oxidation of a model hydroquinone substrate to quantify the density of FeNx centers in Fe-N-C catalysts. The kinetic method is compared with low-temperature Mössbauer spectroscopy, CO pulse chemisorption, and electrochemical reductive stripping of NO derived from NO2 − on a suite of Fe-N-C catalysts prepared by diverse routes and featuring either the exclusive presence of Fe as FeNx sites or the coexistence of aggregated Fe species in addition to FeNx. The FeNx site densities derived from the kinetic method correlate well with those obtained from CO pulse chemisorption and Mössbauer spectroscopy. The broad survey of Fe-N-C materials also reveals the presence of outliers and challenges associated with each site quantification approach. The kinetic method developed here does not require pretreatments that may alter active-site distributions or specialized equipment beyond reaction vessels and standard analytical instrumentation. KW - Active-Site Quantification PY - 2023 U6 - https://doi.org/10.1021/jacs.3c08790 SP - 1 EP - 16 PB - ACS Publications AN - OPUS4-58889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sadowski, A. A1 - Seidel, M. A1 - Al-Lawati, H. A1 - Azizi, E. A1 - Balscheit, Hagen A1 - Böhm, M. A1 - Chen, Lei A1 - van Dijk, I. A1 - Doerich-Stavridis, C. A1 - Kunle Fajuyitan, O. A1 - Filippidis, A. A1 - Winther Fischer, A. A1 - Fischer, C. A1 - Gerasimidis, S. A1 - Karampour, H. A1 - Kathirkamanathan, L. A1 - Subramanian, S. A1 - Topkaya, Cem A1 - Wagner, H. N. R. A1 - Wang, J. A1 - Wang, J. A1 - Kumar Yadav, K. A1 - Yun, X. A1 - Zhang, P. T1 - 8-MW wind turbine tower computational shell buckling benchmark - Part 1: An international ‘round-robin’ exercise N2 - An assessment of the elastic-plastic buckling limit state for multi-strake wind turbine support towers poses a particular challenge for the modern finite element analyst, who must competently navigate numerous modelling choices related to the tug-of-war between meshing and computational cost, the use of solvers that are robust to highly nonlinear behaviour, the potential for multiple near-simultaneously critical failure locations, the complex issue of imperfection sensitivity and finally the interpretation of the data into a safe and economic design. This paper reports on an international ‘round-robin’ exercise conducted in 2022 aiming to take stock of the computational shell buckling expertise around the world which attracted 29 submissions. Participants were asked to perform analyses of increasing complexity on a standardised benchmark of an 8-MW multi-strake steel wind turbine support tower segment, from a linear elastic stress analysis to a linear bifurcation analysis to a geometrically and materially nonlinear buckling analysis with imperfections. The results are a showcase of the significant shell buckling expertise now available in both industry and academia. This paper is the first of a pair. The second paper presents a detailed reference solution to the benchmark, including an illustration of the Eurocode-compliant calibration of two important imperfection forms. KW - Wind turbine tower KW - Computational KW - Shell buckling KW - Benchmark PY - 2023 U6 - https://doi.org/10.1016/j.engfailanal.2023.107124 SN - 1350-6307 VL - 148 SP - 1 EP - 23 PB - Elsevier Science CY - Oxford AN - OPUS4-57019 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher A1 - Wagner, Patrick A1 - Rappsilber, Tim A1 - Liebner, Christian A1 - Hahn, S.-K. A1 - Krause, U. T1 - Harmful effects of lithium-ion battery thermal runaway: scale-up tests from cell to second-life modules N2 - For a comprehensive safety assessment of stationary lithium-ion-battery applications, it is necessary to better understand the consequences of thermal runaway (TR). In this study, experimental tests comprising twelve TR experiments including four single-cell tests, two cell stack tests and six second-life module tests (2.65 kW h and 6.85 kW h) with an NMC-cathode under similar initial conditions were conducted. The temperature (direct at cells/modules and in near field), mass loss, cell/module voltage, and qualitative vent gas composition (Fourier transform infrared (FTIR) and diode laser spectroscopy (DLS) for HF) were measured. The results of the tests showed that the battery TR is accompanied by severe and in some cases violent chemical reactions. In most cases, TR was not accompanied by pregassing of the modules. Jet flames up to a length of 5 m and fragment throwing to distances to more than 30 m were detected. The TR of the tested modules was accompanied by significant mass loss of up to 82%. The maximum HF concentration measured was 76 ppm, whereby the measured HF concentrations in the module tests were not necessarily higher than that in the cell stack tests. Subsequently, an explosion of the released vent gas occurred in one of the tests, resulting in the intensification of the negative consequences. According to the evaluation of the gas measurements with regard to toxicity base on the “Acute Exposure Guideline Levels” (AEGL), there is some concern with regards to CO, which may be equally as important to consider as the release of HF. KW - Large-scale tests KW - Lithium-ion battery KW - Gas emission KW - Thermal runaway KW - Consequences PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-579054 SN - 2046-2069 VL - 13 IS - 30 SP - 20761 EP - 20779 PB - Royal Society of Chemistry (RSC) CY - Cambridge, UK AN - OPUS4-57905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -