TY - JOUR A1 - Yusenko, Kirill A1 - Kabelitz, Anke A1 - Schokel, Alexander A1 - Wagner, Ralf A1 - Prinz, Carsten A1 - Kemnitz, E A1 - Emmerling, Franziska A1 - Krahl, Thoralf A1 - de Oliveira Guilherme Buzanich, Ana T1 - Local Structure of Europium-Doped Luminescent Strontium Fluoride Nanoparticles: Comparative X-ray Absorption Spectroscopy and Diffraction Study N2 - Rare-earth based luminescent materials are key functional components for the rational design of light-conversion smart devices. Stable Eu3+-doped strontium fluoride (SrF2) nanoparticles were prepared at room temperature in ethylene glycol. Their luminescence depends on the Eu content and changes after heat treatment. The crystallinity of heat-treated material increases in comparison with as-synthesized samples. Particles were investigated in solution using X-ray diffraction, small-angle X-ray scattering, and X-ray spectroscopy. After heat treatment, the size of the disordered nanoparticles increases together with a change of their local structure. Interstitial fluoride ions can be localized near Eu3+ ions. Therefore, non-radiative relaxation from other mechanisms is decreased. Knowledge about the cation distribution is key information for understanding the luminescence properties of any material. KW - SrF2 KW - EXAFS KW - Eu PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540094 DO - https://doi.org/10.1002/cnma.202100281 VL - 7 IS - 11 SP - 1221 EP - 1229 PB - Wiley Online Library AN - OPUS4-54009 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Das, Prasenjit A1 - Chakraborty, Gouri A1 - Friese, Nico A1 - Roeser, Jérôme A1 - Prinz, Carsten A1 - Emmerling, Franziska A1 - Schmidt, Johannes A1 - Thomas, Arne T1 - Heteropolyaromatic Covalent Organic Frameworks via One-Pot Multicomponent Reactions N2 - Multicomponent reactions (MCRs) offer a platform to create different chemical structures and linkages for highly stable covalent organic frameworks (COFs). As an illustrative example, the multicomponent Povarov reaction generates 2,4-phenylquinoline from aldehydes and amines in the presence of electron-rich alkenes. In this study, we introduce a new domino reaction to generate unprecedented 2,3-phenylquinoline COFs in the presence of epoxystyrene. This work thus presents, for the first time, structural isomeric COFs produced by multicomponent domino and Povarov reactions. Furthermore, 2,3-phenylquinolines can undergo a Scholl reaction to form extended aromatic linkages. With this approach, we synthesize two thermally and chemically stable MCR-COFs and two heteropolyaromatic COFs using both domino and in situ domino and Scholl reactions. The structure and properties of these COFs are compared with the corresponding 2,4-phenylquinoline-linked COF and imine-COF, and their activity toward benzene and cyclohexane sorption and separation is investigated. The position of the pendant phenyl groups within the COF pore plays a crucial role in facilitating the industrially important sorption and separation of benzene over cyclohexane. This study opens a new avenue to construct heteropolyaromatic COFs via MCR reactions. KW - COF PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604038 DO - https://doi.org/10.1021/jacs.4c02551 SP - 1 EP - 9 PB - American Chemical Society (ACS) AN - OPUS4-60403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chakraborty, Gouri A1 - Das, Prasenjit A1 - Bhattacharya, Biswajit A1 - Prinz, Carsten A1 - Emmerling, Franziska A1 - Thomas, Arne T1 - Room-temperature superprotonic conductivity in COOH-functionalized multicomponent covalent organic frameworks N2 - In solid materials, the development of hydrogen bonding (H-bonding) networks within pores is crucial for efficient proton conductance. In this study, a chemically stable carboxylic acid-functionalized, quinoline-linked 2D microporous covalent organic framework (COF) (Qy-COOH) was synthesized using the Doebner multicomponent reaction (MCR) and compared to a similar framework lacking the –COOH functionality (Qy-H), prepared via an MC Domino reaction. The proton conductivity of the –COOH-functionalized MCR-COF was significantly enhanced, reaching 10−2 S cm−1, attributed to strong H-bonding interactions between water molecules and the dangling –COOH groups within the COF pores. In contrast, the analogous Qy-H framework exhibited a much lower proton conductivity of 10−5 S cm−1, while an imine-based COF showed only 10−6 S cm−1. This work represents the first demonstration of a general strategy to achieve efficient proton conduction in a class of layered 2D –COOH-functionalized COFs, offering superprotonic conductivity without requiring additives at room temperature. The MCR-COF design approach provides a promising pathway for developing highly stable and high-performance proton-conducting materials. KW - Multicomponebt KW - COF KW - Proton Conductivity KW - Superprotonic PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653526 DO - https://doi.org/10.1039/D5SC06953J SN - 2041-6520 SP - 1 EP - 9 PB - Royal Society of Chemistry (RSC) AN - OPUS4-65352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoque, Maroof Arshadul A1 - Sommerfeld, Thomas A1 - Lisec, Jan A1 - Das, Prasenjit A1 - Prinz, Carsten A1 - Heinekamp, Christian A1 - Stolar, Tomislav A1 - Etter, Martin A1 - Rosenberger, David A1 - George, Janine A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska T1 - Mechanochemically Synthesized Covalent Organic Framework Effectively Captures PFAS Contaminants N2 - Per‐ and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants that pose significant health risks, prompting urgent efforts to develop effective removal methods and adsorbers. Covalent organic frameworks (COFs) are metal‐free adsorbers with high stability and tunable porosity. A highly crystalline COF is synthesised mechanochemically using 1,3,5‐tris(4‐aminophenyl)benzene (TAPB) and 1,3,5‐triformylbenzene (TFB). The formation dynamics are monitored in real time with time‐resolved in situ synchrotron X‐ray diffraction. The TAPB‐TFB COF demonstrates good efficiency in eliminating PFAS from water. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are effectively extracted, and most of the adsorption occurred within the first 10 min. Additionally, X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and DFT calculations are employed to elucidate the molecular interactions between PFAS and the COF framework. The rapid and efficient removal of PFAS makes TAPB‐TFB COF a promising material for water treatment applications. KW - COFs KW - Ball-milling KW - PFAS PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648712 DO - https://doi.org/10.1002/smll.202509275 SN - 1613-6810 VL - 21 IS - 44 SP - 1 EP - 8 PB - Wiley CY - Weinheim AN - OPUS4-64871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Al-Terkawi, Abdal-Azim A1 - Prinz, Carsten A1 - Scholz, Gudrun A1 - Kemnitz, Erhard A1 - Emmerling, Franziska T1 - Ca-, Sr-, and Ba-Coordination polymers based on anthranilic acid via mechanochemistry N2 - Ca-, Sr-, and Ba-Based coordination polymers (CPs) were prepared mechanochemically by milling metal-hydroxide samples with anthranilic acid (oABAH). {[Ca(oABA)2(H2O)3]}n consists of one-dimensional polymeric chains that are further connected by a hydrogen-bonding network. {[Sr(oABA)2(H2O)2]·H2O}n is a one-dimensional CP in which water molecules bridge Sr2+ ions and increase the dimensionality by building an extended network. {[Ba(oABA)2(H2O)]}n crystallizes as a two-dimensional CP comprising one bridging water molecule. The cation radii influence the inorganic connectivity and dimensionality of the resulting crystal structures. The crystal structures were refined from powder X-ray diffraction data using the Rietveld method. The local coordination environments were studied via extended X-ray absorption fine structure (EXAFS) measurements. The compounds were further characterized using comprehensive analytical methods such as elemental analysis, thermal analysis, MAS NMR, imaging, and dynamic vapor sorption (DVS) measurements. Compounds 1, 2, and 3 exhibit small surface areas which decrease further after thermal annealing experiments. All compounds exhibit a phase transformation upon heating, which is only reversible in 3. KW - Mechanochemistry KW - XRD PY - 2019 DO - https://doi.org/10.1039/c9dt00991d SN - 1477-9226 SN - 1477-9234 VL - 48 IS - 19 SP - 6513 EP - 6521 PB - Royal Society of Chemistry AN - OPUS4-48014 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beyer, Sebastian A1 - Prinz, Carsten A1 - Schürmann, Robin A1 - Feldmann, Ines A1 - Zimathies, Annett A1 - Blocki, Anna A1 - Bald, Ilko A1 - Schneider, Rudolf A1 - Emmerling, Franziska T1 - Ultra-sonication of ZIF-67 crystals results in ZIF-67 nano-flakes N2 - Zeolitic Imidazolate Frameworks (ZIFs) are crystalline materials that comprise of metal nodes and Imidazole derivatives as linkers. ZIF-67 is often used in polymer composite materials e. g. for gas separation membranes. Post-synthesis treatment of ZIF-67 crystals with ultrasound leads to unforeseen plasticity that resulted in sintered ZIF-67 and ZIF-67 nano-flakes. Consequently, ultrasound increases the external surface area of ZIF-67 which might improve e.g. blending with polymers in composite materials. These new morphologies of ZIF-67 were characterized by transmission electron, scanning electron, and atomic force microscopy. The ultrasound treatment of ZIF-67 did not result in the formation of an amorphous framework or a meta-stable crystal structure as indicated by powder x-ray diffraction. In addition, ultra-sonicated ZIF-67 retained the high gas adsorption capacity and pore size compared to synthesized ZIF-67. The morphological changes are hard to detect with standard analytical methods that are usually utilized for MOF characterization. These findings also suggest that sonochemical treatment of ZIFs leads to structural effects beyond increasing the amount of nucleation clusters during sono-chemical synthesis, which is currently not addressed in the field. KW - ZIF PY - 2016 DO - https://doi.org/10.1002/slct.201601513 SN - 2365-6549 VL - 1 IS - 18 SP - 5905 EP - 5908 AN - OPUS4-38496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stawski, Tomasz A1 - Karafiludis, Stephanos A1 - Standl, Jakob A1 - Ryll, Tom A1 - Schwab, Alexander A1 - Prinz, Carsten A1 - Wolf, Jakob A1 - Kruschwitz, Sabine A1 - Emmerling, Franziska A1 - Völker, Christoph T1 - High-Entropy Metal Phosphate Synthesis: Advancements through Automation and Sequential Learning Optimization N2 - To accelerate high-entropy metal phosphate (HEMP) discovery, we employed a Random Forest regression model within a SLAMD framework. Trained on limited initial data, the model efficiently explored the vast compositional space to predict a novel five-metal phosphate, which was then successfully synthesized and validated experimentally. T2 - AI4 Materials Science and Testing 2025 CY - Berlin, Germany DA - 06.11.2025 KW - Metal phosphates KW - High-entropy KW - Sequential learning PY - 2025 AN - OPUS4-64686 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Prinz, Carsten T1 - Importance of stability studies on porous certified reference materials N2 - In the development of certified reference materials (CRM), it is necessary to examine appropriate materials in advance for homogeneity and stability to meet the criteria of a CRM. In this case, the materials properties are characterized at the actual time without being possible to give a prognosis for suitability in the following years. It is, therefore, necessary to follow the certified material parameters via a monitoring system over the years on sale. For the current development of CRMs, the gained experience from long-term stability studies about the first generation of porous CRMs is significant. This experience is useful to better assess the suitability of candidate materials and thus develop higher quality CRMs in the future. A comparison between the gas sorption CRM materials silica, activated carbons, alpha alumina and anatase titanium oxides will illustrate the importance of long-term stability studies on porous CRMs. T2 - BERM 2018 - 15th International Symposium on Biological and Environmental Reference Materials CY - Berlin, Germany DA - 23.09.2018 KW - Reference material KW - Monitoring KW - Long-term stability PY - 2018 AN - OPUS4-46257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Prinz, Carsten A1 - Zimathies, Annett A1 - Emmerling, Franziska T1 - Experimental raw data sets associated with certified reference material BAM-P114 (titanium dioxide) for comparison of nitrogen and argon sorption, available in the universal adsorption information format (AIF) N2 - These data sets serve as models for calculating the specific surface area (BET method) using gas sorption in accordance with ISO 9277. The present measurements were carried out with nitrogen at 77 Kelvin and argon at 87 Kelvin. It is recommended to use the following requirements for the molecular cross-sectional area: Nitrogen: 0.1620 nm² Argon: 0.1420 nm² Expected specific surface area for nitrogen (BET): 24 to 25 m²/g Expected specific surface area for argon (BET): 20 m²/g Titanium dioxides certified with nitrogen sorption and additionally measured with argon for research purposes were used as sample material. The resulting data sets are intended to serve as comparative data for own measurements and show the differences in sorption behaviour and evaluations between nitrogen and argon. These data are stored in the universal AIF format (adsorption information format), which allows flexible use of the data. KW - Physisorption KW - Specific surface area KW - AIF KW - Argon KW - Nitrogen PY - 2024 DO - https://doi.org/10.5281/zenodo.13283291 PB - Zenodo CY - Geneva AN - OPUS4-60782 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sobina, E. A1 - Zimathis, Anett A1 - Prinz, Carsten A1 - Emmerling, Franziska A1 - de Santis Neves, R. A1 - Galhardo, C. E. A1 - De Robertis, E. A1 - WANG, H. A1 - Mizuno, K. A1 - Kurokawa, A. A1 - Unger, Wolfgang T1 - Final report of CCQM-K136 measurement of porosity properties (specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous Al2O3 N2 - The CCQM-K136 key comparison for determination of the porosity properties of aluminum oxide has been organized jointly by the surface and micro/nano analysis working groups of CCQM to test the abilities of the metrology institutes to measure the porosity properties (specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous Al2O3. Ural Scientific Research Institute for Metrology (UNIIM) acted as the coordinating laboratory for this comparison with BAM Federal Institute for Materials Research and Testing (BAM) as co-coordinating laboratory. Five NMIs and one DI participated in this key comparison. All participants used a gas adsorption method, here nitrogen adsorption at 77.3 K, for analysis according to the international standards ISO 15901-2 and 9277. KW - BET specific surface area KW - Specific adsorption KW - Pore diameter KW - Specific pore volume KW - Nanoporous Al2O3 PY - 2016 UR - http://iopscience.iop.org/article/10.1088/0026-1394/53/1A/08014 DO - https://doi.org/10.1088/0026-1394/53/1A/08014 SN - 0026-1394 SN - 1681-7575 VL - 2016 IS - 53 Technical Supplement SP - Article 08014, 1 EP - 39 PB - IOPscience AN - OPUS4-38282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Olivera, Paulo A1 - Michalchuk, Adam A1 - Marquardt, Julien A1 - Feiler, Torvid A1 - Prinz, Carsten A1 - Torresi, R. A1 - Camargo, P. A1 - Emmerling, Franziska T1 - Investigating the role of reducing agents on mechanosynthesis of Au nanoparticles N2 - Control over the bottom up synthesis of metal nanoparticles (NP) depends on many experimental factors, including the choice of stabilising and reducing agents. By selectively manipulating these species, it is possible to control NP characteristics through solution-phase synthesis strategies. It is not known, however, whether NPs produced from mechanochemical syntheses are governed by the same rules. Using the Au NPs mechanosynthesis as a model system, we investigate how a series of common reducing agents affect both the reduction kinetics and size of Au NPs. It is shown that the relative effects of reducing agents on mechanochemical NP synthesis differ significantly from their role in analogous solution-phase reactions. Hence, strategies developed for control over NP growth in solution are not directly transferrable to environmentally benign mechanochemical approaches. This work demonstrates a clear need for dedicated, systematic studies on NP mechanosynthesis. KW - Mechanochemistry KW - Metal nanoparicels PY - 2020 DO - https://doi.org/10.1039/d0ce00826e VL - 22 IS - 38 SP - 6261 EP - 6267 PB - Royal Society of Chemistry AN - OPUS4-51757 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zauer, M. A1 - Prinz, Carsten A1 - Adolphs, J. A1 - Emmerling, Franziska A1 - Wagenführ, A. T1 - Sorption surfaces and energies of untreated and thermally modified wood evaluated by means of excess surface work (ESW) N2 - Water vapor sorption surface areas and sorption energies of untreated and thermally modified Norway spruce [Picea abies (L.) Karst.], sycamore maple (Acer pseudoplatanus L.) and European ash (Fraxinus excelcior L.) were investigated by means of dynamic vapor sorption (DVS) measurements and excess surface work (ESW) evaluation method, respectively. Adsorption and desorption experiments in the hygroscopic range and desorption tests from water saturation were conducted. Thermodynamically, ESW is the sum of the surface free energy and the isothermal isobaric work of sorption. From the amount adsorbed in the first Minimum a specific surface area similar to the BET surface area can be obtained. The results show that untreated spruce has a significantly higher specific water vapor Sorption surface and sorption energy compared to both hardwoods maple and ash. Thermal modification of the woods leads to a significant reduction of water vapor Sorption surface and sorption energy. The determined surface area and energy are higher in desorption direction than in adsorption direction, whereby the highest values in Desorption direction from water saturation, especially for maple and ash, were obtained. The surface areas calculated by means of the ESW method are similar to the surface areas calculated by means of the BET method, particularly in adsorption direction. KW - Excess surface work KW - Dynamic vapor sorption KW - Wood KW - BET PY - 2018 DO - https://doi.org/10.1007/s00226-018-1021-2 SN - 1432-5225 SN - 0043-7719 VL - 52 IS - 4 SP - 957 EP - 969 PB - Springer CY - Berlin Heidelberg AN - OPUS4-44975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -