TY - JOUR A1 - Stühler, Merlin R. A1 - Makki, Hesam A1 - Silbernagl, Dorothee A1 - Dimde, Mathias A1 - Ludwig, Kai A1 - Tegner, Bengt E. A1 - Greve, Christopher A1 - Rausch, Konstantin A1 - Herzig, Eva M. A1 - Köhler, Anna A1 - Plajer, Alex J. T1 - Flexibility and Dynamicity Enhances and Controls Supramolecular Self-Assembly of Zinc(II) Metallogels N2 - Supramolecular self-assembly of stacked architectures is typically achieved through hydrogen bonding or π–π interactions between monomers constructed from stable and inert bonds. In contrast, coordinative interactions of early metals promise distinct self-assembly behaviour due to more flexible bonding geometries and a wider range of stabilities and exchange kinetics. In this report we demonstrate that tailoring the flexible coordination sphere of Zinc(II) complexes via subtle ligand modification promotes not only one but also three-dimensional self-assembly both thermodynamically and kinetically into higher-order fibrous morphologies, the latter being elucidated by electron tomography. As a result, coordination chemistry can be translated into both nanoscopic (fibre stiffness) and macroscopic (thermal gel stability) material properties. Utilizing dynamicity enables gelation via subcomponent self-assembly, constructing the supramolecular polymer network simultaneously with the monomer. Furthermore, coordinative dis- and reassembly via metal-ligand exchange reactions involving the first and second coordination spheres allows for control over gelation and emission of the system. Our report links concepts in supramolecular self-assembly and coordination chemistry by leveraging the unique bonding interactions that cannot be achieved for traditional monomers, promising applications in stimuli-responsive optoelectronics. KW - Nanomaterial KW - AFM KW - Organometallic KW - Gel PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634221 DO - https://doi.org/10.1002/adfm.202507793 SN - 1616-301X SP - 1 EP - 10 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-63422 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hörmann, Anja Franziska T1 - My surface at a glance: grazing incidence scattering applications N2 - Three literature examples are presented to demonstrate the wide range of applications of grazing incidence scattering. These examples concern 1) the determination of the density of a porous film, 2) how orientation of conducting polymers is observed in grazing incidence scattering, and 3) how the three-dimensional order of nanoparticles is reflected in the data. To conclude we show recent data from the MOUSE lab demonstrating the new capability to observe intermolecular distances in thin films using the molybdenum X-ray source. T2 - Surface Transfer of Pathogens (STOP) - M37 meeting CY - Turin, Italy DA - 11.09.2025 KW - Grazing incidence KW - GISAXS KW - Applications PY - 2025 AN - OPUS4-64115 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hussein, S. A1 - Kühl, A. A. A1 - Golusda, L. A1 - Plattner, C. A1 - Heinze, N. A1 - Sturm, G. A1 - Freise, C. A1 - Traub, Heike A1 - Schannor, Mathias A1 - Trajanoski, Z. A1 - Taupitz, M. A1 - Siegmund, B. A1 - Paclik, D. T1 - Phenotype and function of human monocytes remain mainly unaffected by very small superparamagnetic iron oxide particles N2 - The field of medical application of organic or inorganic nanoparticles is extensive. Medical nanoparticles offer benefits but pose risks. For safe use in diagnostics and therapy, they should be inert, non-immunogenic, non-aggregating, and avoid long-term accumulation in sensitive tissues like bone marrow or the brain. We have developed in-house very small superparamagnetic iron oxide nanoparticles (VSOP), 7 nm in size, which have been successfully used in preclinical magnetic resonance imaging (MRI) to detect intestinal inflammation, neuroinflammation and atherosclerosis. This study examines nanoparticle effects on human blood cells focusing on monocytes in vitro as a first step toward clinical application. Whole blood and monocytes from healthy donors and patients with inflammatory bowel disease were treated with VSOP in vitro and analyzed for changes in their transcriptome, phenotype and function. RNA sequencing of monocytes identified the transferrin receptor as one of the most significantly downregulated genes after VSOP treatment, likely to limit iron uptake. Whereas whole blood RNA sequencing showed significant changes only in three non-coding genes. CyTOF analysis confirmed that VSOP-treated monocytes remain inactive, with no increased proliferation or altered migration. Metabolically, VSOP uptake enhanced the oxygen consumption rate. This effect was likely due to phagocytosis rather than effects mediated by the VSOP itself, as phagocytosis of latex beads showed comparable results. In summary, the analysis of peripheral blood mononuclear cells and monocytes suggests that VSOP treatment has no major impact on immune cell phenotype or function indicating VSOP as a promising diagnostic tool in MRI for inflammatory bowel disease. KW - Imaging KW - Nanoparticle KW - Monocytes KW - Contrast agent KW - Diagnostics KW - ICP-MS KW - LA-ICP-MS KW - VSOP PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-632012 DO - https://doi.org/10.3389/fnano.2025.1584000 SN - 2673-3013 VL - 7 SP - 1 EP - 16 PB - Frontiers Media CY - Lausanne AN - OPUS4-63201 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hülagü, Deniz A1 - Ermilova, Elena A1 - Weise, Matthias A1 - de Préville, Sophie A1 - Hoffmann, Johannes A1 - Morán-Meza, José A1 - Piquemal, Francois A1 - Hertwig, Andreas T1 - Characterization of electrical properties in microstructured ITO layers using spectroscopic ellipsometry N2 - Thin indium tin oxide (ITO) layers are essential in optoelectronics due to their good electrical conductivity, optical transparency in the visible and near infrared regions, substrate adherence and chemical stability. They are widely used in photovoltaic cells, displays, and organic LEDs, and as low emissivity coatings in smart windows and energy-efficient buildings. For nanophotonic devices, understanding the interplay of ITO’s optical and electrical properties is crucial. Electrical resistivity can be tuned by modifying deposition conditions and layer thickness. However, measuring these properties, especially on microstructured surfaces, remains challenging due to the issues like homogeneity and instability during etching. Spectroscopic ellipsometry (SE), a non-destructive and phase-sensitive optical technique, offers precise measurement of thin film thickness and dielectric properties. In this study, we investigated the layer thickness, optical constants, and sheet resistance of unstructured and microstructured ITO thin layers using SE. Unstructured layers were deposited via DC-magnetron sputtering on silicon (Si) substrates in argon (Ar) atmospheres with varying oxygen (O2) flows. This multi-technique approach enhances the understanding of ITO layer structuring and provides robust methodologies for correlating optical and electrical properties, advancing metrology for nanotechnology applications and material science. It also opens the pathway to new reference samples and calibration methods for electrical properties involving device-like structured samples. T2 - ICSE10 - 10th International Conference on Spectroscopic Ellipsometry CY - Boulder, CO, USA DA - 08.06.2025 KW - Ellipsometry KW - Indium tin oxide (ITO) KW - Scanning microwave microscopy (SMM) KW - Sheet resistance calibration standards KW - ITO wet etching PY - 2025 AN - OPUS4-63631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmitt, Johannes T1 - Data acquisition system for single particle inductively coupled plasma mass spectrometry (spICP-MS) with nanosecond time resolution N2 - This study presents our data acquisition system prototype for single particle inductively coupled plasma mass spectrometry (spICP-MS) with nanosecond time resolution (nanoDAQ) and a matching data processing approach for time-resolved data in the nanosecond range. The system continuously samples the secondary electron multiplier (SEM) detector signal with a dwell time of approximately 2 ns and enables detection of gold nanoparticles (AuNP) as small as 7.5 nm with a commercial single quadrupole ICP-MS instrument. [1] Analysis of acquired transient data is based on the temporal distance between detector events and a derived ion event density. It was shown that the inverse logarithm of the distance between detector events is proportional to particle size. Also, the number of detector events per particle can be used to calibrate and determine the particle number concentration (PNC) of a nanoparticle dispersion. Particle-by-particle-based analysis of ion event density and other parameters derived from nanosecond time resolution show promising results. High data acquisition frequency of the systems allows recording of a statistically significant number of data points in 60 s or less, which leaves only the sample uptake and rinsing steps as remaining factors for limiting the total measurement time. T2 - 20th European Winter Conference on Plasma Spectrochemistry CY - Berlin, Germany DA - 02.03.2025 KW - ICP-MS KW - Instrumentation KW - Nano KW - Nanoparticle Characterization PY - 2025 AN - OPUS4-63599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Speight, Isaiah R. A1 - Ardila-Fierro, Karen J. A1 - Hernández, José G. A1 - Emmerling, Franziska A1 - Michalchuk, Adam A. L. A1 - García, Felipe A1 - Colacino, Evelina A1 - Mack, James T1 - Ball milling for mechanochemical reactions N2 - Mechanochemistry is an emerging field with the potential to pave the way for sustainable chemistry. Although the use of mechanical force to initiate chemical reactions has been recognized for millennia, it has often taken a backseat to thermal and photonic methods. Over the past 30 years, mechanochemistry has seen a resurgence of interest, attracting researchers across the globe. Despite its proven ability to address numerous challenges within the chemical community, mechanochemistry remains on the periphery. This Primer serves as a valuable guide for conducting mechanochemical reactions by ball milling, offering an overview of the processes, methods, tools and terminology necessary to embark on research in this field. It also highlights persistent hurdles such as equipment standardization, understanding the impact of new discoveries and the lack of predictability of reaction outcomes. The Primer’s focus is on how mechanochemical ball milling is used in various chemical transformations, distinguishing it from other forms of mechanochemistry discussed in the literature. With a promising future, this Primer serves as a gateway for those aspiring to contribute to the field’s advancement. KW - Mechanochemistry KW - Ball milling KW - Upscaling PY - 2025 DO - https://doi.org/10.1038/s43586-025-00401-2 SN - 2662-8449 VL - 5 IS - 1 SP - 1 EP - 18 PB - Springer Science and Business Media LLC AN - OPUS4-63447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosenbusch, Ivo A1 - Arai, Marylyn Setsuko A1 - Rizzo, Fabio A1 - de Camargo, Andrea S. S. A1 - Ravoo, Bart Jan T1 - A host–guest approach to ratiometric pH sensing using upconversion nanoparticles N2 - A new pH nanosensor based on β-NaYF4:Yb3+/Tm3+ upconversion nanoparticles functionalized with cyclodextrin and a pH-sensitive adamantane-modified nitrobenzoxadiazole dye (NBD-Ad). KW - Host-guest materials KW - Upconversion nanoparticles KW - Ratiometric optical sensors KW - pH sensing PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637722 DO - https://doi.org/10.1039/d5na00145e SN - 2516-0230 VL - 7 IS - 13 SP - 4142 EP - 4151 PB - Royal Society of Chemistry (RSC) AN - OPUS4-63772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Go, Eun Sul A1 - Hong, Eun Ji A1 - Lee, Ji Yeong A1 - Stolar, Tomislav A1 - Peterson, Gregory I. A1 - Emmerling, Franziska L. A1 - Kim, Kyoungsoo A1 - Kim, Jeung Gon T1 - Insights into Mechanochemical Solid-State Ball-Milling Reaction: Monitoring Transition from Heterogeneous to Homogeneous Conditions N2 - As mechanochemical synthesis has advanced significantly, there has been intense interest in understanding the underlying mechanisms of these reactions. Given that many mechanochemical processes are conducted in the solid-state without solvation yet sometimes yield faster reactions than those in solution, we sought to address the following question: Are mechanochemical reactions homo- or heterogeneous? To investigate, we employed a model system involving the mixing and copolymerization of l-lactide (LLA) and d-lactide (DLA), monitored through powder X-ray diffraction (PXRD), nuclear magnetic resonance, and differential scanning calorimetry. In situ and ex situ PXRD analyses of the mixture of LLA and DLA showed that vibratory ball milling rapidly transformed the initially heterogeneous lactide mixture into a homogeneous phase within one min due to collisions between the balls and the jar. By varying the milling conditions, we were able to regulate the level of mixing, which subsequently influenced the copolymerization outcomes. In the solid-state ball-milling copolymerization of LLA and DLA in the presence of a catalyst and initiator, multiblock copolymers of poly(l-lactic acid) and poly(d-lactic acid) were formed within one min during the early stage of the reaction, when incomplete mixing of the monomers led to a process governed by phase heterogeneity. In contrast, prolonged polymerization promoted conditions approaching homogeneity, ultimately yielding atactic poly(lactic acid). This transition from heterogeneous to homogeneous reactions is a distinctive feature compared to conventional homogeneous reactions, potentially leading to mechano-exclusive reaction designs. KW - Mechanochemistry KW - Ball-milling KW - Homogeneous reaction KW - Heterogeneous reaction PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638008 DO - https://doi.org/10.1021/jacsau.5c00322 SN - 2691-3704 VL - 5 IS - 6 SP - 2720 EP - 2727 PB - American Chemical Society (ACS) AN - OPUS4-63800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Deffo, Gullit A1 - Tamo, Arnaud Kamdem A1 - Fotsop, Cyrille Ghislain A1 - Tchoumi, Honorine Hortense Bougna A1 - Talla, Donald Eric Njiajo A1 - Wabo, Calice Gildas A1 - Deussi, Marcel Cédric Ngaha A1 - Temgoua, Ranil Clément Tonleu A1 - Doungmo, Giscard A1 - Njanja, Evangeline A1 - Tonle, Ignas Kenfack A1 - Puzari, Panchanan A1 - Birkemeyer, Claudia A1 - Ngameni, Emmanuel T1 - Metal-organic framework-based materials: From synthesis and characterization routes to electrochemical sensing applications N2 - Metal-organic frameworks (MOFs) are formed by coordination bonds between organic ligands and metal ions or clusters. Their key properties, including high surface area, porosity, and adjustable functionalities, enable diverse applications in gas separation, catalysis, energy storage, luminescence, and more recently, the development of electrochemical sensors. In this review, we provide an overview of various electrochemical methods and discuss different MOF-based electrochemical sensors reported in the literature. We focus on the synthesis of MOFs, their characterization, and the preparation of MOF-based working electrodes for electroanalysis. A brief history of MOFs, along with their nomenclature, classifications, and features, is discussed to provide a chronological understanding of MOFs before delving into their electroanalytical uses. Recent advancements in the use of MOFs as electrode materials for electrochemical sensing have been extensively reviewed and documented, highlighting their increasing relevance in various analytical fields. This review investigates the key properties of MOFs that make them suitable candidates for sensing applications and the ability for post-synthesis modifications to improve their selectivity and sensitivity. It also examines the challenges associated with the synthesis and modification of MOFs, including issues related to scalability, eproducibility, and the stability of the materials under operational conditions. Furthermore, the review discusses potential future directions for the use of MOFs in electrochemical sensing, emphasizing their role as electrode materials to enhance the sensitivity and selectivity of modified sensors for sustainable applications. KW - Metal-organic frameworks (MOFs) KW - MOF synthesis and characterization KW - Electrochemical sensors KW - Electroanalysis PY - 2025 DO - https://doi.org/10.1016/j.ccr.2025.216680 SN - 0010-8545 VL - 536 SP - 1 EP - 78 PB - Elsevier B.V. AN - OPUS4-63742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ruehle, Bastian T1 - Workflow generation, management, and semantic description for Self-Driving Labs N2 - The software backend that controls the robotic hardware and runs the synthesis workflows is a very important component of any Self-Driving Lab (SDL). On the one hand, it has to deal with orchestrating and managing complex and task-specific hardware through low-level communication protocols and plan and use the available resources as efficiently as possible while executing (parallelized) workflows, on the other hand, it is the interface the users use to communicate with this highly complex platform, and as such, it needs to be as helpful and user-friendly as possible. This includes the AI-aided experimental design in which the system helps the user to decide which experiment to run next, providing automated data analysis from characterization measurements, and offering easy to understand tools and graphical user interfaces for generating the workflows that are executed on the platform. Lastly, the specificity of the workflows and their dependence on the hardware and software of the SDLs necessitates a common description or ontology for making them easily interchangeable and interoperable between different platforms and labs. In this contribution, we present several key aspects of “Minerva-OS”, the central backend that orchestrates the syntheses workflows of our SDL for Nano- and Advanced Materials Syntheses [1]. One key feature is the resource management or “traffic control” for scheduling and executing parallel reactions in a multi-threaded environment. Another is the interface with data analysis algorithms from in-line, at-line, and off-line measurements. Here, we will give examples of how automatic image segmentation of electron microscopy images with the help of AI [2] can be used for reducing the “data analysis bottleneck” from an off-line measurement. We will also discuss, compare, and show benchmarks of various machine learning (ML) algorithms that are currently implemented in the backend and can be used for ML-guided, closed-loop material optimization in our SDL. Lastly, we will show our recent efforts [3] in making the workflow generation on SDLs more user-friendly by using large language models to generate executable workflows automatically from synthesis procedures given in natural language and user-friendly graphical user interfaces based on node editors that also allow for knowledge graph extraction from the workflows. In this context, we are currently also working on an ontology for representing the process steps of the workflows, which will greatly facilitate the semantic description and interoperability of workflows between different SDL hardware and software platforms. T2 - Accelerate 2025 CY - Toronto, Canada DA - 11.08.2025 KW - Nanomaterials KW - Advanced Materials KW - Workflows KW - Machine Learning KW - SDL PY - 2025 AN - OPUS4-63936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ruehle, Bastian T1 - Nano- and Advanced Materials Synthesis in a Self-Driving Lab (SDL) N2 - Nano- and advanced materials have been recognized as a key enabling technology of the 21st century, due to their high potential of driving innovations in new clean energy technologies, sustainable manufacturing by substitution of critical raw materials and replacement of hazardous substances, breakthroughs in energy conversion and storage, improvement of the environmental performance of products and processes, and facilitation of circularity. Consequently, improving tools that enhance the development and optimization cycle of nano- and advanced materials is crucial. In this contribution, we present our Self-Driving Lab (SDL) for Nano and Advanced Materials [1], that integrates robotics for batched autonomous synthesis – from molecular precursors to fully purified nanomaterials – with automated characterization and data analysis, for a complete and reliable nanomaterial synthesis workflow. By fully automating these three process steps for seven different materials from five representative, completely different classes of nano- and advanced materials (metal, metal oxide, silica, metal organic framework, and core–shell particles) that follow different reaction mechanisms, we demonstrate the great versatility and flexibility of the platform. The system also exhibits high modularity and adaptability in terms of reaction scales and incorporates in-line characterization measurement of hydrodynamic diameter, zeta potential, and optical properties (absorbance, fluorescence) of the nanomaterials. We discuss the excellent reproducibility of the various materials synthesized on the platform in terms of particle size and size distribution, and the adaptability and modularity that allows access to a diverse set of nanomaterial classes. These features underscore the SDL’s potential as a transformative tool for advancing and accelerating the development of nano- and advanced materials, offering solutions for a sustainable and environmentally responsible future. T2 - Accelerate 2025 CY - Toronto, Canada DA - 11.08.2025 KW - Nanomaterials KW - Advanced Materials KW - Automation KW - SDL KW - MAP PY - 2025 AN - OPUS4-63935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Huber, Norbert T1 - Testing and analysis of materials and components ‒ an expedition from lab to field in a digitally transforming world N2 - In an era where digital transformation is reshaping every facet of our lives, the field of material science and engineering is no exception. This presentation delves into the exciting journey of material and component testing, tracing its path from the confines of the laboratory to the vast expanse of real-world applications, with a particular focus on enhancing safety and reliability. We will explore how modern techniques are pushing the boundaries of conventional material testing, revealing new dimensions of material behavior and performance that are crucial for ensuring safety. The integration of in situ quality control within production processes is revolutionizing manufacturing, ensuring unparalleled precision and reliability, which are essential for maintaining high safety standards. As we venture into the realm of Structural Health Monitoring (SHM), discover how cutting-edge technologies are being deployed in field applications, from infrastructure to renewable energy sectors, to monitor and ensure the safety and integrity of critical systems. The presentation will also offer a glimpse into the future, where centralized systems for research data management and innovative digital initiatives promise to transform the landscape of material testing and analysis, further bolstering safety measures. Join us to uncover how these advancements are not only enhancing safety and reliability but also paving the way for a digitally interconnected world. T2 - MaterialsWeek 2025 CY - Frankfurt am Main, Germany DA - 02.04.2025 KW - Characterization KW - Materials testing KW - In situ quality control KW - Digitalization PY - 2025 AN - OPUS4-63918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lemiasheuski, Anton A1 - Wehrkamp, F. A1 - Bajer, Evgenia A1 - Sonnenburg, Elke A1 - Göbel, Artur A1 - Porohovoj, Ilja A1 - Bettge, Dirk A1 - Pfennig, Anja T1 - Practical application of an automated 3D metallography system for the reconstruction and microstructural analysis of porosity in a sintered steel N2 - In the 3D microstructural analysis of a digital twin of porosity in the sintered steel Astaloy CrA, pore shape, average pore size as well as pore distribution will be analyzed. Porosity plays a major role in powder-metallurgical materials since it greatly impacts the mechanical properties of these materials and therefore represents a key parameter in their characterization. Based on the robot-assisted automated serial sectioning and imaging (RASI) system of the Federal Institute for Materials Research and Testing (BAM, Bundesanstalt für Materialforschung und Prüfung) in Berlin, the technique of metallographic serial sectioning will be used to image the microstructure and reconstruct a digital 3D twin from the stack of images obtained. Compared with an individual 2D microsection, the quantitative microstructural analysis of this 3D twin will enable more accurate conclusions on the shape, size and distribution of pores. This paper will detail the key steps in 3D microstructural analysis, including the metallographic preparation routine, the imaging technique, image alignment as well as the segmentation of pores. After the methodology has been described, the results of the quantitative microstructural analysis will be presented and the validity of quantitative parameters of 3D and 2D images will be compared and discussed. The analysis of more than 10,000 pores revealed a correlation between pore shape and pore size. It was also found that a 2D representation of the material surface is insufficient for a precise quantitative characterization of porosity. N2 - In der 3D-Gefügeanalyse eines digitalen Zwillings von Poren in einem Sinterstahl des Typs Astaloy CrA werden sowohl die Porenform als auch die durchschnittliche Porengröße und -verteilung analysiert. Die Porosität spielt in pulvermetallurgischen Werkstoffen eine große Rolle, da sie erheblich die mechanischen Eigenschaften beeinflusst und daher bei der Charakterisierung dieser Werkstoffe ein wichtiger Parameter ist. Basierend auf der Verwendung des Robot-Assisted Automated Serial-Sectioning and Imaging (RASI)-Systems der Bundesanstalt für Materialforschung und Prüfung (BAM) in Berlin, wird das metallographische Serienschnittverfahren genutzt, um das Gefüge aufzunehmen und aus dem Bildstapel einen digitalen 3D-Zwilling zu rekonstruieren. Verglichen zu einem 2D-Einzelschliff ermöglicht die quantitative Gefügeanalyse dieses 3D-Zwillings präzisere Aussagen zu Porenform, -größe und -verteilung. Diese Arbeit beschreibt die wesentlichen Schritte, die für eine 3D-Gefügeanalyse nötig sind, darunter die metallografische Präparationsroutine, das Bildgebungs-Verfahren, das Alignment der Bilder sowie die Segmentierung der Poren. Im Anschluss an die methodische Darstellung werden die Ergebnisse der quantitativen Gefügeanalyse präsentiert und ein Vergleich zwischen der Aussagekraft der quantitativen Parameter von 3D- und 2D-Abbildungen diskutiert. Bei der Analyse von über 10.000 Poren konnte eine Korrelation zwischen der Form und der Porengröße aufgezeigt werden. Weiterhin konnte aufgezeigt werden, dass eine 2D-Abbildung der Werkstoffoberfläche nicht ausreichend für eine eindeutige quantitative Beschreibung der Porosität ist. KW - 3D Metallographie KW - RASI KW - Porenstruktur PY - 2025 DO - https://doi.org/10.1515/pm-2025-0049 SN - 2195-8599 VL - 62 IS - 8 SP - 516 EP - 535 PB - De Gruyter Brill AN - OPUS4-63930 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ruehle, Bastian T1 - Nano- and Advanced Materials Synthesis in a Self-Driving Lab (SDL) N2 - Nano- and advanced materials have been recognized as a key enabling technology of the 21st century, due to their high potential of driving innovations in new clean energy technologies, sustainable manufacturing by substitution of critical raw materials and replacement of hazardous substances, breakthroughs in energy conversion and storage, improvement of the environmental performance of products and processes, and facilitation of circularity. Consequently, improving tools that enhance the development and optimization cycle of nano- and advanced materials is crucial. In this contribution, we present our Self-Driving Lab (SDL) for Nano and Advanced Materials [1], that integrates robotics for batched autonomous synthesis – from molecular precursors to fully purified nanomaterials – with automated characterization and data analysis, for a complete and reliable nanomaterial synthesis workflow. By fully automating these three process steps for seven different materials from five representative, completely different classes of nano- and advanced materials (metal, metal oxide, silica, metal organic framework, and core–shell particles) that follow different reaction mechanisms, we demonstrate the great versatility and flexibility of the platform. The system also exhibits high modularity and adaptability in terms of reaction scales and incorporates in-line characterization measurement of hydrodynamic diameter, zeta potential, and optical properties (absorbance, fluorescence) of the nanomaterials. We discuss the excellent reproducibility of the various materials synthesized on the platform in terms of particle size and size distribution, and the adaptability and modularity that allows access to a diverse set of nanomaterial classes. These features underscore the SDL’s potential as a transformative tool for advancing and accelerating the development of nano- and advanced materials, offering solutions for a sustainable and environmentally responsible future. T2 - Accelerate 2025 CY - Toronto, Canada DA - 11.08.2025 KW - Nanomaterials KW - Advanced Materials KW - Automation KW - SDL KW - MAP PY - 2025 AN - OPUS4-63934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Walter, Keven A1 - Hoch, Dominik P. A1 - Hertweck, Leon A1 - Balasubramanian, Kannan A1 - Geisler, Jonas A1 - Röllig, Mathias A1 - Neubert, Tilmann J. A1 - Börner, Hans G. T1 - Unlocking the Essence of Lignin: High‐Performance Adhesives That Bond via Thiol‐Catechol Connectivities and Debond on Electrochemical Command N2 - AbstractThe next generation of adhesives requires effective debonding capabilities that can be triggered on demand to enable advanced circular repair and recycling strategies. A new class of lignin‐inspired, two‐component (2K) structural adhesives offers bonding strengths of up to 20 MPa and clean, on‐command electrochemical debonding within 5–30 min. The debonding is induced by a distinct electrochemical oxidation of thiol‐catechol connectivities (TCCs) within the entire adhesive network, enforcing rapid and clean adhesive failure on the cathodic substrate side. The TCC‐functionalities are formed during curing by a thiol‐quinone Michael‐type polyaddition, reacting polyester‐based trithiols with tris‐quinones as lignin‐inspired minimal building blocks. The structural adhesive can be fine‐tuned by adjusting the formulation. The addition of carbon black and ionic liquids facilitates the desired electrochemical transformation of TCC‐catechols to TCC‐quinones. Applying only 9 V for 5–30 min, leads to clean debonding with 72–86% loss of shear strength. A comprehensive study of curing, bonding, and debonding behavior by rheological, spectroscopic, and electrochemical investigations reveals the debonding mechanism by correlating catechol oxidation to adhesive performance. The electrochemical debonding capability of TCC‐structural adhesives is demonstrated in a functional prototype, where on‐command detachment of a cover glass from a display device is achieved within 6.5 min. KW - Lignin-inspired KW - Electrochemical-Debonding KW - Thiol-Catechol-Connectivity (TCC) KW - Michael-Type Polyaddition KW - On-Demand Adhesive Failure PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639674 DO - https://doi.org/10.1002/adma.202510463 SN - 0935-9648 SP - 1 EP - 10 PB - Wiley VHC-Verlag CY - 69451 Weinheim AN - OPUS4-63967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yildirim, Arda A1 - Haug, T. C. V. A1 - Fröba, M. A1 - Huber, P. A1 - Schönhals, Andreas T1 - Molecular fluctuations in mixed-metal MOF-74: influence of the metal composition N2 - A selected series of metal–organic frameworks M-MOF-74 (M = Mg, Co, Ni) and mixed metal MM-MOF-74 (Mg/Co or Mg/Ni) with different compositions of metal atoms have been prepared and further investigated by broadband dielectric spectroscopy (BDS) in a wide temperature range. The dielectric spectra show at least two relaxation processes. Process-A is observed only for the Ni-containing MOFs and is attributed to localized fluctuations of the metal oxide corners. Relaxation processes-B and -C are observed for all prepared MOFs, except that process-B is not observed for Ni-MOF-74. Large-angle fluctuations such as free rotations of the linkers can be excluded due to the structure of MOF-74, but small-angle fluctuations such as torsions are possible. According to numerical simulations carried out for MOF-74, process-B can be attributed to inward and outward fluctuations of the linkers relative to the pore center. Process-C is related to small-angle rotational fluctuations of the linker together with co-rotations of the metal nodes. The latter interpretation is supported by the dependence of the activation energy of the relaxation rate of process-C on the metal composition of the MOFs, which is discussed in terms of the bond lengths between the metal atoms and the linker which decrease in the sequence Mg, Co and Ni. KW - Metal Organic Frameworks PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639378 DO - https://doi.org/10.1039/d5ra05357a SN - 2046-2069 VL - 15 IS - 35 SP - 29109 EP - 29118 PB - Royal Society of Chemistry (RSC) AN - OPUS4-63937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolmangadi, Mohamed A. A1 - Raab, A. R. A1 - Szymoniak, Paulina A1 - Li, Z. A1 - Huber, P. A1 - Laschat, S. A1 - Schönhals, Andreas T1 - Molecular mobility and electrical conductivity of amino acid-based (DOPA) ionic liquid crystals in the bulk state and nanoconfinement N2 - This study explores the molecular mobility, phase behavior, and electrical conductivity of dihydroxyphenylalanine-based ionic liquid crystals (DOPAn, with alkyl side chains n = 12, 14, 16) featuring cyclic guanidiniumchloride headgroups, in both bulk and nanoconfined states. Using broadband dielectric spectroscopy, differential scanning calorimetry, and fast scanning calorimetry, the research uncovers a complex interplay between molecular structure, self-assembly, and molecular mobility. In bulk, DOPAn shows a phase sequence from plastic crystalline to hexagonal columnar and isotropic phases, driven by superdisc formation and columnar organization. Multiple relaxation processes are identified: localized side-chain dynamics (γ-relaxation), ionic headgroup or core motions (α1-relaxation), and cooperative alkyl domain fluctuations (α2-relaxation). Conductivity decreases with increasing side chain length. Under nanoconfinement in anodic aluminum oxide membranes, phase behavior changes: the Colh–Iso transition is suppressed, and a new α3-relaxation appears, linked to dynamics in an adsorbed interfacial layer. DC conductivity drops by up to four orders of magnitude due to confinement effects, altered molecular orientation, and phase transitions—especially the emergence of a nematic-like state in DOPA16. These findings highlight the importance of molecular design, pore geometry, and surface chemistry in tuning ionic liquid crystal properties for advanced applications in nanofluidics, ion transport, and responsive materials. KW - Ionic Liquid Crystals PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639657 DO - https://doi.org/10.1039/d5cp02406d SN - 1463-9084 SP - 1 EP - 17 PB - Royal Society of Chemistry (RSC) AN - OPUS4-63965 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Bio-Based Vitrimers: Cracking the Code of Recyclability, Exchange Reactions and Flame Retardancy N2 - Vitrimers are a promising class of sustainable materials that offer an alternative to traditional epoxy thermosets in line with circular economy principles. Built on covalent adaptive networks (CANs), they can rearrange their chemical bonds in response to external stimuli, giving them properties like recyclability, shape-memory, and self-healing. These materials combine the strength of thermosets with the reprocessability of thermoplastics, making them attractive for next-generation applications. This study focuses on a bio-based vitrimer made from glycerol triglycidyl ether (GTE) and a vanillin-derived imine hardener (VA), which reacts through catalyst-free imine metathesis. To better understand the recyclability mechanisms of such systems, especially the dynamic bond exchange, we apply a comprehensive suite of techniques including dielectric spectroscopy, neutron scattering, mechanical analysis, and calorimetry. By linking molecular dynamics with macroscopic performance, the work aims to support the development of vitrimers as practical, recyclable materials. T2 - EPF2025 - European Polymer Congress CY - Groningen, The Netherlands DA - 22.06.2025 KW - Polymer recycling PY - 2025 AN - OPUS4-63859 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hülagü, Deniz A1 - Ermilova, Elena A1 - Weise, Matthias A1 - de Préville, Sophie A1 - Hoffmann, Johannes A1 - Morán‐Meza, José A1 - Piquemal, François A1 - Hertwig, Andreas T1 - Multimethod Electrical Characterization of Thin Indium Tin Oxide Films: Structuring and Calibration Sample Development for Scanning Probe Microscopy N2 - Indium tin oxide (ITO), a transparent conductive oxide, is widely used in optoelectronic applications due to its electrical conductivity, optical transparency, and chemical stability. This study employs spectroscopic ellipsometry (SE) to analyze ITO layers, enabling nondestructive determination of film thickness, dielectric functions, and bulk conductivity. Electrical properties derived from SE are compared with those obtained using the four‐point probe method (4PM) to improve metrological tools for nanotechnology applications and optimize deposition process monitoring for better control of film properties. This work also investigates the chemical stability of ITO layers under etching conditions and explores the development of new sheet resistance standards for scanning microwave microscopy (SMM). The results show that ITO resistivity, calculated from fitted SE data, increases with oxygen flow rate up to 5 cm3(STP) min−1. Good agreement is observed between sheet resistance values obtained by SE and 4PM up to 3 cm3(STP) min−1. Additionally, the sheet resistance values of a distinct set of microstructured ITO samples with different ITO layer thicknesses are determined by SMM, which are highly consistent with those obtained by the 4PM. KW - Ellipsometry KW - Indium tin oxide (ITO) KW - Scanning microwave microscopy (SMM) KW - Sheet resistance calibration standards KW - ITO wet etching PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626242 DO - https://doi.org/10.1002/pssa.202400871 SN - 1862-6300 VL - 222 IS - 14 SP - 1 EP - 18 PB - Wiley CY - Hoboken, New Jersey, USA AN - OPUS4-62624 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Nanoscale Confinement Effects in Thin Films of Rigid-Backbone Polymers N2 - Thin polymer films play a crucial role in modern technologies, with applications spanning flexible electronics, membranes, coatings, and nanodevices. Their reduced dimensions result in unique physical behavior, often deviating significantly from bulk properties due to confinement and interfacial effects. In this study, we investigate how nanoscale confinement and polymer–substrate interactions influence the structural and dynamic properties of supported thin films of two rigid-backbone polymers: poly(bisphenol A carbonate) (PBAC) and polysulfone (PSU). Emphasis was placed on the development of adsorbed interfacial layers, molecular mobility, and the glass transition behavior as functions of film thickness and thermal history. Using a multimodal experimental approach—including Atomic Force Microscopy (AFM), Broadband Dielectric Spectroscopy (BDS), Differential and Fast Scanning Calorimetry (DSC, FSC), and Ellipsometry—we characterized adsorption kinetics, desorption processes, and segmental dynamics across a wide range of thicknesses and annealing conditions. Special attention was given to the formation and growth regimes of the adsorbed polymer layers, including a newly observed pre-growth stage, and their effect on thermal and dielectric relaxation behavior. To probe dynamics in ultrathin films, two dielectric electrode configurations—crossed electrode capacitors and nanostructured electrodes—were employed, enabling measurements down to 10 nm and isolated adsorbed layer. This comprehensive analysis provides insight into how one-dimensional confinement and interfacial interactions modulate macromolecular behavior, which is critical for the design of functional nanostructured polymeric systems in advanced applications. T2 - 10th International Discussion Meeting on Relaxations in Complex Systems (10thIDMRCS) CY - Barcelona, Spanien DA - 20.06.2025 KW - Thin films PY - 2025 AN - OPUS4-63858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -