TY - JOUR
A1 - Merkel, Stefan
A1 - Köppen, Robert
A1 - Koch, Matthias
A1 - Emmerling, Franziska
A1 - Nehls, Irene
T1 - Lysergol monohydrate
N2 - In the title compound [systematic name: (7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3,2-fg]quinoline-9-yl)methanol monohydrate], C16H18N2O·H2O, the non-aromatic ring (ring C of the ergoline skeleton) directly fused to the aromatic rings is nearly planar, with a maximum deviation of 0.659 (3) Å, and shows an envelope conformation. In the crystal, hydrogen bonds between the lysergol and water molecules contribute to the formation of layers parallel to (10-2).
PY - 2012
DO - https://doi.org/10.1107/S1600536812002632
SN - 1600-5368
VL - 68
IS - 2
SP - o523, sup1
EP - sup8
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-25401
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Merkel, Stefan
A1 - Köppen, Robert
A1 - Koch, Matthias
A1 - Emmerling, Franziska
A1 - Nehls, Irene
T1 - Lumi-ergometrine - structural identification and occurrence in sclerotia
N2 - The fungus Claviceps purpurea grows on grasses
and cereal grains and produces six predominant ergot
alkaloids. These toxic substances undergo different transformation
reactions during storage and cereal processing. One
of these reactions is the addition of water to a double bond in
the ergoline skeleton. Since light is required for this process,
the substances formed were named lumi-ergot alkaloids.
From these, a new asymmetric carbon and consequently two
epimers with different polarities are formed. For investigations
of lumi-ergot alkaloids, ergometrine was used exemplarily
as it represents one of the six ergot alkaloids
predominantly formed by Claviceps purpurea. The main
reaction product, the less polar compound of the two lumiergometrine
epimers, was separated by HPLC and unambiguously
identified as 10-(S)-lumi-ergometrine using X-ray
structural analysis. A HPLC-MS/MS method was developed
for the detection of this substance in sclerotia extracts. Using
this method, the existence of both epimeric forms of lumiergometrine
could be proved in the sclerotia. This is the first
time that the existence of a lumi-transformation product of
ergot alkaloids was proved in naturally grown samples.
KW - Lumi-ergot alkaloids
KW - Sclerotia
KW - Claviceps purpurea
KW - HPLC-MS/MS
PY - 2012
DO - https://doi.org/10.1007/s12550-011-0116-5
SN - 0178-7888
VL - 28
IS - 1
SP - 59
EP - 66
PB - Springer
CY - Berlin; Heidelberg
AN - OPUS4-25442
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Boldyreva, E.
A1 - Belenguer, A. M.
A1 - Emmerling, Franziska
A1 - Boldyrev, V. V.
T1 - Tribochemistry, mechanical alloying, mechanochemistry: what is in a name?
N2 - Over the decades, the application of mechanical force to influence chemical reactions has been called by various names: mechanochemistry, tribochemistry, mechanical alloying, to name but a few. The evolution of these terms has largely mirrored the understanding of the field. But what is meant by these terms, why have they evolved, and does it really matter how a process is called? Which parameters should be defined to describe unambiguously the experimental conditions such that others can reproduce the results, or to allow a meaningful comparison between processes explored under different conditions? Can the information on the process be encoded in a clear, concise, and self-explanatory way? We address these questions in this Opinion contribution, which we hope will spark timely and constructive discussion across the international mechanochemistry community.
KW - Mechanochemistry
KW - Tribochemistry
KW - Mechanical alloying
KW - Tribology
KW - Mechanical activation
KW - Nomenclature
KW - Mechanochemical pictographs
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523291
DO - https://doi.org/10.3389/fchem.2021.685789
SN - 2296-2646
VL - 9
SP - 1
EP - 29
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-52329
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
T1 - Time-Resolved InSitu Monitoring of Mechanochemical Reactions
N2 - Mechanochemical transformations offer environmentally benign synthesis routes, whilst enhancing both the speed and selec-tivity of reactions. In this light, mechanochemistry promises to trans-form the way in which chemistry is done in both academia and indus-try but is greatly hindered by a current lack in mechanistic understand-ing. The continued development and use of time-resolved in situ(TRIS) approaches to monitor mechanochemical reactions provides a new dimension to elucidatethese fascinating transformations. We here discuss recent trends in method development that have pushed the boundaries of mechanochemical research. New features of mech-anochemical reactions obtained by TRIS techniques are subse-quently discussed, shedding light on how different TRISapproaches have beenused. Emphasis is placed on the strength of combining complementary techniques. Finally, we outline our views for the po-tential of TRIS methods in mechanochemical research, towards es-tablishing a new, environmentally benign paradigm in the chemical sciences
KW - Mechanochemistry
KW - Material synthesis
KW - Green chemistry
PY - 2022
DO - https://doi.org/10.1002/anie.202117270
SN - 1433-7851
SP - 1
EP - 15
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54321
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mönch, Bettina
A1 - Emmerling, Franziska
A1 - Kraus, Werner
A1 - Becker, Roland
A1 - Nehls, Irene
T1 - n-Propyl 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside
N2 - The title compound [systematic name: (2R,3R,4S,5R,6R) 2-(acetoxymethyl)-6-propoxytetrahydro-2H-pyran-3,4,5-triyl triacetate], C17H26O10, was formed by a Koenigs-Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide and n-propanol. The central ring adopts a chair conformation. The crystal does not contain any significant interactions such as hydrogen bonds.
PY - 2013
DO - https://doi.org/10.1107/S1600536812051495
SN - 1600-5368
VL - 69
IS - Part 2
SP - o158, sup-1 - sup-7
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-27439
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mönch, Bettina
A1 - Emmerling, Franziska
A1 - Kraus, Werner
A1 - Becker, Roland
A1 - Nehls, Irene
T1 - Isopropyl 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside
N2 - The title compound, C17H26O10, was formed by a Koenigs-Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide and propan-2-ol. The central ring adopts a chair conformation. The crystal does not contain any significant intermolecular interactions.
PY - 2013
DO - https://doi.org/10.1107/S1600536812051483
SN - 1600-5368
VL - 69
IS - Part 2
SP - o157, sup-1 - sup-7
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-27572
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mönch, Bettina
A1 - Gebert, Antje
A1 - Emmerling, Franziska
A1 - Becker, Roland
A1 - Nehls, Irene
T1 - Koenigs-Knorr reaction of fusel alcohols with methyl (1-bromo-2,3,4-tri-O-acetyl-alpha-D-glucopyranosid)uronate leading to the protected alkyl glucuronides-crystal structures and high resolution 1H and 13C NMR data
N2 - Crystal structures and high resolution 1H and 13C NMR spectral data for methyl (alkyl 2,3,4-tri-O-acetyl-β-D-glucopyranosid)uronates (alkyl = methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, i-butyl, n-pentyl, 2-methyl-1-butyl and 3-methyl-1-butyl) are presented.
KW - D-Glucuronic acid derivates
KW - X-ray analysis
KW - High resolution NMR
KW - Anomeric configuration
KW - Synthesis
PY - 2012
DO - https://doi.org/10.1016/j.carres.2012.01.002
SN - 0008-6215
SN - 1873-426X
VL - 352
SP - 186
EP - 190
PB - Elsevier
CY - Amsterdam
AN - OPUS4-25759
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mönch, Bettina
A1 - Kraus, Werner
A1 - Köppen, Robert
A1 - Emmerling, Franziska
T1 - The different conformations and crystal structures of dihydroergocristine
N2 - The identification of different forms of dihydroergocristine (DHEC) was carried out by crystallization from different organic solvents. DHEC was identified as potential template for molecularly imprinted polymers (MIPs) for the epimeric specific analysis of ergot alkaloids (EAs) in food. DHEC was crystallized from different solvents in order to mimic the typical MIP synthesis conditions. Four new solvatomorphs of DHEC were obtained. All solvatomorphs contain a water molecule in the crystal structure, whereas three compounds contain an additional solvent molecule. Based on the conformation of DHEC a comparison with typical EA molecules was possible. The analysis showed that DHEC is a suitable template for MIPs for EAs.
PY - 2016
DO - https://doi.org/10.1016/j.molstruc.2015.10.008
SN - 0022-2860
SN - 1872-8014
SN - 0377-046X
VL - 1105
SP - 389
EP - 395
PB - Elsevier B.V.
CY - Amsterdam
AN - OPUS4-35009
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nag, Sayak
A1 - Emmerling, Franziska
A1 - Tothadi, Srinu
A1 - Bhattacharya, Biswajit
A1 - Ghosh, Soumyajit
T1 - Distinct photomechanical responses of two new 1,3-dimethylbarbituric acid derivative crystals
N2 - We demonstrate two distinct photomechanical responses (i.e. photomechanical bending and photosalient bursting) of two new 1,3-dimethylbarbituric acid derivative crystals based on tailoring their substituents and the modulation of their spacers.
KW - Crystal engineering
KW - Fexible crystals
PY - 2024
DO - https://doi.org/10.1039/D4CE00233D
SP - 1
EP - 12
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60141
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nehls, Irene
A1 - Hanebeck, Olaf
A1 - Becker, Roland
A1 - Emmerling, Franziska
T1 - N-(beta-carboxyethyl)-alpha-isoleucine
N2 - The title compound, {2-[(2-carbamoylethyl)amino]-3-methylpentanoic acid}, C9H18N2O3, is of interest with respect to its biological activity. It was formed during an addition reaction between acrylamide and the amino acid isoleucine. The crystal structure is a three-dimensional network built up by intermolecular N–H···O and O–H···N hydrogen bonds.
KW - Acrylamid
KW - Isoleucin
KW - Derivatisierung
PY - 2013
DO - https://doi.org/10.1107/S160053681205146X
SN - 1600-5368
VL - 69
IS - Part 2
SP - o172-o173, sup-1 - sup-7
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-27573
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nguyen, Thi Yen
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Direct evidence of polyamorphism in paracetamol
N2 - While polymorphism is a common phenomenon in the crystallization processes of organic compounds, polyamorphism has gained importance only recently. Using sophisticated sample environments and applying in situ scattering methods and vibrational spectroscopy, the complete crystallization process of organic compounds from solution can be traced and characterized. Diffuse scattering from amorphous intermediates can be investigated by analyzing the atomic pair distribution function (PDF) to gain further insights into molecular pre-orientation. The crystallization behavior of paracetamol was studied exemplarily under defined, surface-free conditions. Based on the choice of the solvent, the formation of different polymorphs is promoted. The thermodynamically stable form I and the metastable orthorhombic form II could be isolated in pure form directly from solution. For both polymorphs, the crystallization from solution proceeds via a distinct amorphous precursor phase. PDF analyses of these different amorphous states indicate a specific pre-orientation of the analyte molecules introduced by the solvent. The resulting crystalline polymorph is already imprinted in these proto-crystalline precursors. Direct experimental evidence for the polyamorphism of paracetamol is provided.
PY - 2015
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351366
DO - https://doi.org/10.1039/C5CE01583A
SN - 1466-8033
VL - 17
IS - 47
SP - 9029
EP - 9036
PB - Royal Society of Chemistry
CY - London, UK
AN - OPUS4-35136
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nguyen, Thi Yen
A1 - Roessler, Ernst
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - Control of organic polymorph formation: crystallization pathways in acoustically levitated droplets
N2 - Theoretical and experimental studies indicate that crystal nucleation can take more complex pathways than expected on the ground of the classical nucleation theory. Among these pathways are the formation of pre-nucleation clusters and amorphous precursor phases. A direct in situ observation of the different pathways of nucleation from solution is challenging since the paths can be influenced by heterogeneous nucleation sites, such as container walls. Here, we provide insights into the crystallization process using the in situ combination of an acoustic levitator, Raman spectroscopy, and X-ray scattering. The contactless sample holder enables the observation of homogeneous crystallization processes and the detection of intermediates and final crystalline forms. We provide evidence for the existence of multiple pathways of nucleation based on the investigation of the crystallization of organic molecules from different solvents. Starting from a diluted solution, a supersaturation is reached during the experiment due to the evaporation of the solvent. The highly supersaturated solution reveals different pathways of crystallization. Depending on the degree of supersaturation either the thermodynamically stable or the metastable crystal form is observed.
KW - Crystallization
KW - In situ XRD
KW - Polymorphism
KW - Polyamorphism
KW - Raman spectroscopy
PY - 2017
DO - https://doi.org/10.1515/zkri-2016-1964
SN - 2194-4946
SN - 2196-7105
VL - 232
IS - 1-3
SP - 15
EP - 24
PB - De Gruyter
CY - Berlin
AN - OPUS4-39708
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Noack, J.
A1 - Emmerling, Franziska
A1 - Kirmse, H.
A1 - Kemnitz, E.
T1 - Sols of nanosized magnesium fluoride: formation and stabilisation of nanoparticles
N2 - The formation of magnesium fluoride sols and xerogels according to the fluorolytic sol–gel synthesis based on the reaction of Mg(OMe)2 with non-aqueous HF has been thoroughly investigated by X-ray scattering (WAXS/XRD), TEM, SAXS, DLS and 19F MAS NMR spectroscopy. Mechanistic insights were gained by following the reaction progress and formation of intermediate phases of the fluorination of magnesium alkoxides. For F:Mg ratios of 0.3 and 0.4 the formation of two crystalline phases was observed containing the recently obtained compound [Mg6F2(OCH3)10(CH3OH)14] hexanuclear dicubane units. The stoichiometric reaction yields magnesium fluoride nanoparticles with crystallite sizes below 5 nm, which show broad reflections in the X-ray diffraction pattern. Metal fluoride sols prepared by this way undergo tremendous changes over the first several weeks after synthesis. Immediately after the fluorination, particles of about 120 nm—probably agglomerates—are formed, which break apart in the course of about one month of ageing and low-viscous, transparent sols with particles of about 12 nm are obtained. At the same time structural re-organisation processes within the magnesium fluoride particles are observed by an increase of the (110) reflection in WAXS.
KW - Surface modification
KW - Colloidal particles
KW - Gold nanoparticles
KW - Gel synthesis
KW - Small-angle scattering
KW - Oxide
KW - Polyelectrolytes
KW - Aggregation
KW - Dispersion
PY - 2011
DO - https://doi.org/10.1039/c1jm11943e
SN - 0959-9428
SN - 1364-5501
VL - 21
IS - 38
SP - 15015
EP - 15021
PB - Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-26183
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Opitz, P.
A1 - Asta, M.
A1 - Fernandez-Martinez, A.
A1 - Panthöfer, M.
A1 - Kabelitz, Anke
A1 - Emmerling, Franziska
A1 - Mondeshki, M.
A1 - Tremel, W.
T1 - Monitoring a Mechanochemical Syntheses of Isostructural Luminescent Cocrystals of 9-Anthracenecarboxylic Acid with two Dipyridines Coformers
N2 - Amorphous calcium carbonate (ACC) is an important precursor in the biomineralization of crystalline CaCO3. In nature, it serves as a storage material or as a permanent structural element, whose lifetime is regulated by an organic matrix. The relevance of ACC in materials science is primarily related to our understanding of CaCO3 crystallization pathways and CaCO3/(bio)polymer nanocomposites. ACC can be synthesized by liquid–liquid phase separation, and it is typically stabilized with macromolecules. We have prepared ACC by milling calcite in a planetary ball mill. Phosphate “impurities” were added in the form of monetite (CaHPO4) to substitute the carbonate anions, thereby stabilizing ACC by substitutional disorder. The phosphate anions do not simply replace the carbonate anions. They undergo shear-driven acid/base and condensation reactions, where stoichiometric (10%) phosphate contents are required for the amorphization to be complete. The phosphate anions generate a strained network that hinders ACC recrystallization kinetically. The amorphization reaction and the structure of BM-ACC were studied by quantitative Fourier transform infrared spectroscopy and solid state 31P, 13C, and 1H magic angle spinning nuclear magnetic resonance spectroscopy, which are highly sensitive to symmetry changes of the local environment. In the first—and fast—reaction step, the CO32– anions are protonated by the HPO42– groups. The formation of unprecedented hydrogen carbonate (HCO3–) and orthophosphate anions appears to be the driving force of the reaction, because the phosphate group has a higher Coulomb energy and the tetrahedral PO43– unit can fill space more efficiently. In a competing second—and slow—reaction step, pyrophosphate anions are formed in a condensation reaction. No pyrophosphates are formed at higher carbonate contents. High strain leads to such a large energy barrier that any reaction is suppressed. Our findings aid in the understanding of the mechanochemical amorphization of calcium carbonate and emphasize the effect of impurities for the stabilization of the amorphous phases in general. Our approach allowed the synthesis of new amorphous alkaline earth defect variants containing the unique HCO3– anion. Our approach outlines a general strategy to obtain new amorphous solids for a variety of carbonate/phosphate systems that offer promise as biomaterials for bone regeneration.
KW - Crystallization
KW - Mechanochemistry
KW - PDF
PY - 2020
DO - https://doi.org/10.1021/acs.cgd.0c00912
VL - 20
IS - 10
SP - 6831
EP - 6846
PB - American Chemical Society
AN - OPUS4-51819
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Opitz, P.
A1 - Besch, L.
A1 - Panthöfer, M.
A1 - Kabelitz, Anke
A1 - Unger, R.
A1 - Emmerling, Franziska
A1 - Mondeshki, M.
A1 - Tremel, W.
T1 - Insights into the In Vitro Formation of Apatite from Mg‐Stabilized Amorphous Calcium Carbonate
N2 - A protein‐free formation of bone‐like apatite from amorphous precursors through ball‐milling is reported. Mg2+ ions are crucial to achieve full amorphization of CaCO3. Mg2+ incorporation generates defects which strongly retard a recrystallization of ball‐milled Mg‐doped amorphous calcium carbonate (BM‐aMCC), which promotes the growth of osteoblastic and endothelial cells in simulated body fluid and has no effect on endothelial cell gene expression. Ex situ snapshots of the processes revealed the reaction mechanisms. For low Mg contents (<30%) a two phase system consisting of Mg‐doped amorphous calcium carbonate (ACC) and calcite “impurities” was formed. For high (>40%) Mg2+ contents, BM‐aMCC follows a different crystallization path via magnesian calcite and monohydrocalcite to aragonite. While pure ACC crystallizes rapidly to calcite in aqueous media, Mg‐doped ACC forms in the presence of phosphate ions bone‐like hydroxycarbonate apatite (dahllite), a carbonate apatite with carbonate substitution in both type A (OH−) and type B (PO43−) sites, which grows on calcite “impurities” via heterogeneous nucleation. This process produces an endotoxin‐free material and makes BM‐aMCC an excellent “ion storage buffer” that promotes cell growth by stimulating cell viability and metabolism with promising applications in the treatment of bone defects and bone degenerative diseases.
KW - Total Scattering
KW - XRD
KW - Mechanochemistry
PY - 2020
DO - https://doi.org/10.1002/adfm.202007830
VL - 31
IS - 3
SP - 7830
PB - Wiley VHC-Verlag
AN - OPUS4-51761
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Orgzall, I.
A1 - Emmerling, Franziska
A1 - Schulz, B.
A1 - Franco, O.
T1 - High-pressure studies on molecular crystals - relations between structure and high-pressure behavior
N2 - This paper summarizes attempts to understand structureproperty relationships for a large class of aromatic diphenyl-1,3,4-oxadiazole molecules. Starting from the investigation of the crystal structure several common packing motifs as well as characteristic differences are derived. Many different molecules show a rather planar conformation in the solid state. A stronger intermolecular twist is only observed for compounds with substituents occupying the ortho-positions of the phenyl rings. Most crystal structures are characterized by the formation of stacks leading to intense ππ acceptordonor interactions between oxadiazole and phenyl rings. High-pressure investigations result in a soft compression behavior typical for organic molecular crystals. The bulk behavior may be described by the Murnaghan equation of state with similar coefficients (bulk modulus and its pressure derivative) for nearly all investigated compounds but also for related substances. The compression shows a strong anisotropy resulting from the specific features and packing motifs of the crystal structure. This is clearly indicated by a corresponding strain analysis. Additionally to the crystal structure the Raman spectrum was also investigated under increasing pressure. The different pressure behavior of external and internal modes reflects the difference between intra- and intermolecular interactions.
KW - Diphenyl-1,3,4-oxadiazole
KW - Crystal structure
KW - High pressure investigations
KW - Equation of state
KW - Strain analysis
KW - Raman investigations
PY - 2008
DO - https://doi.org/10.1088/0953-8984/20/29/295206
SN - 0953-8984
SN - 1361-648X
VL - 20
SP - 295206-1 - 295206-15
PB - IOP Publ. Ltd.
CY - Bristol
AN - OPUS4-17784
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ortel, Erik
A1 - Fischer, A.
A1 - Chuenchom, L.
A1 - Polte, Jörg
A1 - Emmerling, Franziska
A1 - Smarsly, B.M.
A1 - Kraehnert, R.
T1 - New triblock copolymer templates, PEO-PB-PEO, for the synthesis of titania films with controlles mesopore size, wall thickness, and bimodal porosity
N2 - The synthesis and properties of a series of new structure-directing triblock copolymers with PEO-PB-PEO structure (PEO = poly(ethylene oxide) and PB = polybutadiene) and their application as superior pore-templates for the preparation of mesoporous titania coatings are reported. Starting from either TiCl4 or from preformed TiO2 nanocrystalline building blocks, mesoporous crystalline titanium oxide films with a significant degree of mesoscopic ordered pores are derived, and the pore size can be controlled by the molecular mass of the template polymer. Moreover, the triblock copolymers form stable micelles already at very low concentration, i.e., prior to solvent evaporation during the evaporation-induced self-assembly process (EISA). Consequently, the thickness of pore walls can be controlled independently of pore size by changing the polymer-to-precursor ratio. Thus, unprecedented control of wall thickness in the structure of mesoporous oxide coatings is achieved. In addition, the micelle formation of the new template polymers is sufficiently distinct from that of typical commercial PPO-PEO-PPO polymers (Pluronics; PPO = poly(propylene oxide)), so that a combination of both polymers facilitates bimodal porosity via dual micelle templating.
KW - Mesoporous materials
KW - Titanium oxide films
KW - Anatase nanoparticles
KW - PEO-PB-PEO
KW - Dual templating
PY - 2012
DO - https://doi.org/10.1002/smll.201101520
SN - 1613-6810
SN - 1613-6829
VL - 8
IS - 2
SP - 298
EP - 309
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-26277
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ortel, Erik
A1 - Polte, J.
A1 - Bernsmeier, D.
A1 - Eckhardt, B.
A1 - Paul, B.
A1 - Bergmann, A.
A1 - Strasser, P.
A1 - Emmerling, Franziska
A1 - Kraehnert, R.
T1 - Pd/TiO2 coatings with template-controlled mesopore structure as highly active hydrogenation catalyst
N2 - Micro-structured reactors offer excellent mass and heat transport capabilities and can therefore sustain very high reaction rates and space–time-yields also for highly exothermic catalytic reactions. However, such high rates cannot be reached when the reactors are coated or filled with conventional catalysts powders. We present a strategy for the direct synthesis of highly active wall-coated supported catalysts via co-deposition of a pore template (here micelles formed from PEO-b-PPO-b-PEO) and a precursors for the metal oxide (TiCl4) along with a compatible precursor for the active metal (PdCl2). The obtained catalytic coatings possess a template-controlled open pore structure and excellent mechanical stability. Moreover, the active metal is highly dispersed and well-distributed across the coating also at high Pd loadings. The corresponding high activity along with rapid mass transfer enabled by the open pore system results in the best space–time-yields in the gas-phase hydrogenation of butadiene reported so far in literature for a supported catalyst.
KW - Titanium oxide films
KW - Palladium nanoparticle
KW - Wall-coated supported catalysts
KW - Template-controlled mesoporous materials
KW - Hydrogenation of 1,3-butadiene
PY - 2015
DO - https://doi.org/10.1016/j.apcata.2014.12.044
SN - 0926-860X
SN - 1873-3875
VL - 493
SP - 25
EP - 32
PB - Elsevier
CY - Amsterdam
AN - OPUS4-32465
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pakrashy, S.
A1 - Mandal, P. K.
A1 - Goswami, J. N.
A1 - Dey, S. K.
A1 - Choudhury, S. M.
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Alasmary, F. A.
A1 - Dolai, M.
T1 - Bioinformatics and Network Pharmacology of the First Crystal Structured Clerodin: Anticancer and Antioxidant Potential against Human Breast Carcinoma Cell
N2 - Clerodin was isolated from the medicinal plant Clerodendrum infortunatum, and CSD search showed the first crystal structure of clerodin by a single-crystal X-ray diffraction study. We checked its binding potential with target proteins by docking and conducted network pharmacology analysis, ADMET analysis, in silico pathway analysis, normal mode analysis (NMA), and cytotoxic activity studies to evaluate clerodin as a potential anticancer agent. The cell viability studies of clerodin on the human breast carcinoma cell line (MCF-7) showed toxicity on MCF-7 cells but no toxicity toward normal human lymphocyte cells (HLCs). The anticancer mechanism of clerodin was validated by its enhanced capacity to produce intracellular reactive oxygen species (ROS) and to lower the reduced glutathione content in MCF-7 cells.
KW - Anticancer
KW - Clerodin
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567600
DO - https://doi.org/10.1021/acsomega.2c07173
SN - 2470-1343
VL - 7
IS - 51
SP - 48572
EP - 48582
PB - ACS Publ.
CY - Washington, DC
AN - OPUS4-56760
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paris, O.
A1 - Li, C.
A1 - Siegel, S.
A1 - Weseloh, G.
A1 - Emmerling, Franziska
A1 - Riesemeier, Heinrich
A1 - Erko, A.
A1 - Fratzl, P.
T1 - A new experimental station for simultaneous X-ray microbeam scanning for small- and wide-angle scattering and fluorescence at BESSY II
N2 - A new instrument for simultaneous microbeam small- and wide-angle X-ray scattering and X-ray fluorescence (SAXS/WAXS/XRF) is presented. The instrument is installed at the microfocus beamline at BESSY II and provides a beam of 10 µm size with a flux of about 109 photons s-1. A SAXS resolution up to 500 Å d-spacing and a range of scattering vectors of almost three orders of magnitude are reached by using a large-area high-resolution CCD-based detector for simultaneous SAXS/WAXS. The instrument is particularly suited for scanning SAXS/WAXS/XRF experiments on hierarchically structured biological tissues. The necessary infrastructure, such as a cryo-stream facility and an on-site preparation laboratory for biological specimens, are available.
KW - Scanning SAXS
KW - Scanning WAXS
KW - Microbeam
KW - Synchrotron radiation
PY - 2007
SN - 0021-8898
SN - 1600-5767
VL - 40
IS - Supplement
SP - s466
EP - s470
PB - Blackwell
CY - Oxford
AN - OPUS4-15049
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Adam, Christian
A1 - Adamczyk, Burkart
A1 - Müller, Ralf
A1 - Michaelis, Matthias
A1 - Krahl, T.
A1 - Emmerling, Franziska
T1 - Nanocrystalline and stacking-disordered beta-cristobalite AlPO4: the now deciphered main constituent of a municipal sewage sludge ash from a full-scale incineration facility
N2 - For the first time evidence is provided that a nanocrystalline and stacking-disordered, chemically stabilized β-cristobalite form of AlPO4 occurs in a sewage sludge ash (SSA). This proof is based on a combined X-ray powder diffraction and X-ray fluorescence investigation of an SSA produced at a large-scale fluidized bed incineration facility serving a catching area with a population of 2 million. The structural and chemical characterization was carried out on 'as received' SSA samples as well as on solid residues remaining after leaching this SSA in sodium hydroxide solution. Thus, it was ascertained that the observed nanocrystalline and stacking-disordered cristobalite-like component belongs to the aluminum phosphate component of this SSA, rather than to its silicon dioxide component. In addition, a direct proof is presented that the chemically stabilized β-cristobalite form of AlPO4 does crystallize from X-ray amorphous precursors under conditions that mimic the huge heating rate and short retention time (just seconds at T ≈ 850°C), typical for fluidized bed incinerators.
KW - Aluminum phosphate
KW - Chemical stabilization of high-temperature forms
KW - Cristobalite form
KW - Stacking disorder
KW - Incinerator ash
KW - Sewage sludge ash
PY - 2015
DO - https://doi.org/10.1017/S0885715614001213
SN - 0885-7156
VL - 30
IS - Supplement S 1
SP - S31
EP - S35
PB - JCPDS
CY - Swarthmore, Pa.
AN - OPUS4-33435
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Adam, Christian
A1 - Adamczyk, Burkart
A1 - Müller, Ralf
A1 - Schadrack, Reinhard
A1 - Michaelis, Matthias
A1 - Emmerling, Franziska
A1 - Reuther, H.
A1 - Menzel, Michael
T1 - Evidence of formation of the tridymite form of AlPO4 in some municipal sewage sludge ashes
N2 - Evidence is provided that the tridymite component observed in the X-ray diffraction patterns of some sewage sludge ashes (SSAs) should not be interpreted as the tridymite modification of SiO2 but as the tridymite form of AlPO4. This proof is based on a combined X-ray Powder Diffraction (XRD), X-ray fluorescence (XRF) and Mossbauer spectroscopy investigation of two SSAs produced at two fluidized bed incineration facilities, located in different municipalities and operated differently. The structural and chemical characterization was carried out on the 'as received' SSA samples as well as on the residues of these two SSAs pretreated by leaching in citric acid. In addition, direct proof is presented that the tridymite form of AlPO4 does crystallize from X-ray amorphous precursors under conditions that mimic the huge heating rate and short retention time (just seconds at T ≈ 850 °C) typical for fluidized bed incinerators.
KW - Aluminium phosphate
KW - Ash
KW - Fly ash
KW - Incinerator ash
KW - Sewage sludge ash
KW - Tridymite form
PY - 2013
DO - https://doi.org/10.1017/S0885715613000869
SN - 0885-7156
VL - 28
IS - S2
SP - S425
EP - S435
PB - JCPDS
CY - Swarthmore, Pa.
AN - OPUS4-29703
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Adam, Christian
A1 - Michaelis, Matthias
A1 - Kley, Gerd
A1 - Emmerling, Franziska
A1 - Simon, Franz-Georg
T1 - Reaction sequences in the thermochemical treatment of sewage sludge ashes revealed by X-ray powder diffraction - A contribution to the European project SUSAN
N2 - The sequence of reactions accompanying the thermochemical treatment of an iron- and aluminium-bearing sewage sludge ash was ascertained by investigating two systematic series of samples. The ash was thermochemically treated in a lab-scale rotary furnace after mixing it with a chlorine-donor, either CaCl2 or MgCl2. Within each of these two sample series only a single process parameter, the reaction temperature, was varied, namely between 350 and 1050°C. It was found, that among the numerous crystalline phases present in the raw ash only quartz and hematite continue to exist after thermochemical treatments carried out at 1050°C, whereas all other components undergo at least one decomposition-recrystallization cycle. Some of the components re-crystallize even several times. It was proved that the restructuring of the calcium- and phosphorus-bearing mineral phases proceeds via the formation of chlorspodioside, Ca2PO4Cl. The influence of the type of chlorine-donor on the final product was elucidated in detail and - to the best of our knowledge - for the first time crystalline AlPO4 was found in a sewage sludge ash and its decomposition was investigated, too.
KW - XRD
KW - Phosphorus recovery
KW - Sewage sludge ash
KW - Urban mining
KW - Fertilizers
PY - 2009
DO - https://doi.org/10.1524/zksu.2009.0068
SN - 0930-486X
VL - 30 EPDIC 2008
SP - 459
EP - 464
PB - Oldenbourg
CY - München
AN - OPUS4-20562
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Adam, Christian
A1 - Reuther, H.
A1 - Vogel, Christian
A1 - Adamczyk, Burkart
A1 - Menzel, Michael
A1 - Emmerling, Franziska
A1 - Simon, Franz-Georg
T1 - First identification of the tridymite form of AlPO4 in municipal sewage sludge ash
N2 - Sewage sludge and sewage sludge ashes (SSA) are produced in huge amounts at municipal waste water treatment plants (WWTP) all around the world and have become an issue for many urbanized areas. To deal with this unceasing mass flow in an ecologically and economically responsible way a comprehensive chemical and structural characterization of all types of SSA is needed. X-ray powder diffraction (XRD) is one of the most promising analytical methods for this task. Although, there has been ample chemical evidence showing that many SSA contain aluminium phosphate as a major component up to now no aluminium phosphate or aluminium-rich mixed phosphate phase has been reported to be identified by XRD in a SSA produced at a mono-incineration facility. The outcome of the present com-bined XRD and Mossbauer spectroscopy investigation provides comprehensive evidence closing this gap for the first time.
KW - Aluminium phosphate
KW - AlPO4
KW - Tridymite
KW - Sewage sludge ash
KW - Incinerator
KW - Ash
PY - 2011
DO - https://doi.org/10.1524/zkpr.2011.0067
SN - 0044-2968
VL - 1
SP - 443
EP - 448
PB - Oldenbourg
CY - München
AN - OPUS4-24297
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Adamczyk, Burkart
A1 - Formanek, P.
A1 - Meyer, Christian
A1 - Krüger, O.
A1 - Scharf, Holger
A1 - Reinsch, Stefan
A1 - Ostermann, Markus
A1 - Nofz, Marianne
A1 - Jäger, Christian
A1 - Adam, Christian
A1 - Emmerling, Franziska
T1 - Nanocrystalline and stacking-disordered beta-cristobalite AlPO4 chemically stabilized at room temperature: synthesis, physical characterization, and X-ray powder diffraction data
N2 - This paper reports the first successful synthesis and the structural characterization of nanocrystalline and stacking-disordered β-cristobalite AlPO4 that is chemically stabilized down to room temperature and free of crystalline impurity phases. Several batches of the title compound were synthesized and thoroughly characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy mapping in SEM, solid-state 31P nuclear magnetic resonance (31P-NMR) spectroscopy including the TRAPDOR method, differential thermal analysis (DTA), gas-sorption methods, optical Emission spectroscopy, X-ray fluorescence spectroscopy, and ion chromatography. Parameters that are critical for the synthesis were identified and optimized. The synthesis procedure yields reproducible results and is well documented. A high-quality XRD pattern of the title compound is presented, which was collected with monochromatic copper radiation at room temperature in a wide 2θ range of 5°–100°.
KW - Stabilization of high-temperature phase at RT
KW - Nanochrystalline AlPO4
KW - Beta-christobalite structure type
KW - High-cristobalite form
KW - Aluminium phosphate
PY - 2017
DO - https://doi.org/10.1017/S0885715617000537
SN - 1945-7413
SN - 0885-7156
VL - 32
IS - S1
SP - S193
EP - S200
PB - JCPDS-ICDD
CY - Cambridge
AN - OPUS4-42235
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Adamczyk, Burkart
A1 - Kley, Gerd
A1 - Adam, Karin
A1 - Emmerling, Franziska
A1 - Simon, Franz-Georg
T1 - New horizons of the structural characterization of stainless steel slags by X-ray powder diffraction
KW - AOD slag
KW - Metal recovery
KW - Metallurgy
KW - Rietveld method
KW - Slags
KW - Stainless steel slags
KW - Quantitative phase analysis (QPA)
PY - 2007
SN - 0930-486X
VL - 26
SP - 61
EP - 66
PB - Oldenbourg
CY - München
AN - OPUS4-16666
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peplinski, Burkhard
A1 - Fitch, A.N.
A1 - Evans, A.
A1 - Ibberson, R.M.
A1 - Többens, D.M.
A1 - Cranswick, L.M.D.
A1 - Dörfel, Ilona
A1 - Emmerling, Franziska
A1 - Matschat, Ralf
T1 - Structural characterization of a coarse-grained transparent silicon carbide powder by a combination of powder diffraction techniques
N2 - Diffraction of hard synchrotron radiation as well as constant-wavelength and time-of-flight neutron diffraction were used for the structural characterization of a silicon carbide powder having extremely low levels of chemical impurities, high perfection of the crystalline lattice and a grain size of up to 150 µm. The presence of three polytypes was ascertained and the ratios of their mass fractions were determined to be w15R : w6H = 0.002,3(8) and w4H : w6H = 0.000,6(2).
KW - Silicon carbide
KW - Polytypes
KW - Phase quantification
KW - Reference material
PY - 2009
DO - https://doi.org/10.1524/zksu.2009.0009
SN - 0930-486X
VL - 30 EPDIC 2008
SP - 61
EP - 66
PB - Oldenbourg
CY - München
AN - OPUS4-20561
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peters, Stefan
A1 - Kunkel, Benny
A1 - Cakir, Cafer Tufan
A1 - Kabelitz, Anke
A1 - Witte, Steffen
A1 - Bernstein, Thomas
A1 - Bartling, Stephan
A1 - Radtke, Martin
A1 - Emmerling, Franziska
A1 - Abdel-Mageed, Ali Mohamed
A1 - Wohlrab, Sebastian
A1 - Guilherme Buzanich, Ana
T1 - Time-, space- and energy-resolved in situ characterization of catalysts by X-ray absorption spectroscopy
N2 - A novel setup for dispersive X-ray absorption spectroscopy (XAS) with simultaneous resolution of space, time and energy for in situ characterization of solid materials is demonstrated.
KW - Dispersive XAS
KW - Catalysis
KW - In situ
KW - Structure analysis
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584924
DO - https://doi.org/10.1039/d3cc03277a
SN - 1359-7345
SP - 1
EP - 4
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58492
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Ahner, T. T.
A1 - Delißen, Friedmar
A1 - Sokolov, S.
A1 - Emmerling, Franziska
A1 - Thünemann, Andreas
A1 - Kraehnert, R.
T1 - Mechanism of gold nanoparticle formation in the classical citrate synthesis method derived from coupled in situ XANES and SAXS evaluation
PY - 2010
DO - https://doi.org/10.1021/ja906506j
SN - 0002-7863
SN - 1520-5126
VL - 132
IS - 4
SP - 1296
EP - 1301
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-23048
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Emmerling, Franziska
A1 - Radtke, Martin
A1 - Reinholz, Uwe
A1 - Riesemeier, Heinrich
A1 - Thünemann, Andreas
T1 - Real-time monitoring of copolymer stabilized growing gold nanoparticles
N2 - A great challenge in the production of nanoparticles with defined sizes and properties is to control their growth in situ. We developed a dedicated combined small-angle X-ray scattering (SAXS) and X-ray absorption spectroscopy (XAS) setup to monitor nanoparticle formation in solution. The capabilities of simultaneously deriving particle sizes and oxidation states of atoms/ions are illustrated for the formation of spherical gold nanoparticles by the reduction of hydrogen tetrachloroaureate (HAuCl4). Particles with initial radii of 4.60 ± 0.10 nm and final radii of 5.67 ± 0.10 nm were produced in a levitated droplet with a volume of 4 µL. An ethylene oxide/propylene oxide triblock copolymer PEO-PPO-PEO (Pluronic F-127) functions as reducing agent and colloidal stabilizer. XANES shows in situ how the gold was reduced in the droplet from Au(III) to Au(0), and simultaneously SAXS recorded the size distribution of the formed nanoparticles. It is shown that the final particle number is reached quickly. Thereafter, only the particles sizes increase. Comparison of XANES and SAXS shows that the quantity of Au(0) is higher than the quantity of gold located in the nanoparticles while the particles are growing. Finally, all the Au(0) is found in the nanoparticles. We tentatively attribute this finding to the pseudo crown ether effect of the polymer surfactant that kinetically stabilizes gold atoms when formed from gold ions within their protecting cavity. A simple burst mechanism for the gold nanoparticle formation is the consequence. The possibility of an inhomogeneous particles structure with an enhanced density near the particle surface is discussed.
PY - 2010
DO - https://doi.org/10.1021/la903829q
SN - 0743-7463
SN - 1520-5827
VL - 26
IS - 8
SP - 5889
EP - 5894
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-21223
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Erler, Robert
A1 - Thünemann, Andreas
A1 - Emmerling, Franziska
A1 - Kraehnert, R.
T1 - SAXS in combination with a free liquid jet for improved time-resolved in situ studies of the nucleation and growth of nanoparticles
PY - 2010
DO - https://doi.org/10.1039/c0cc03238g
SN - 0022-4936
SN - 0009-241x
SN - 1359-7345
SN - 1364-548x
VL - 46
IS - 48
SP - 9209
EP - 9211
PB - Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-23049
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Erler, Robert
A1 - Thünemann, Andreas
A1 - Sokolov, S.
A1 - Ahner, T. T.
A1 - Rademann, K.
A1 - Emmerling, Franziska
A1 - Kraehnert, R.
T1 - Nucleation and growth of gold nanoparticles studies via in situ small angle X-ray scattering at millisecond time resolution
N2 - Gold nanoparticles (AuNP) were prepared by the homogeneous mixing of continuous flows of an aqueous tetrachloroauric acid solution and a sodium borohydride solution applying a microstructured static mixer. The online characterization and screening of this fast process (~2 s) was enabled by coupling a micromixer operating in continuous-flow mode with a conventional in-house small angle X-ray scattering (SAXS) setup. This online characterization technique enables the time-resolved investigation of the growth process of the nanoparticles from an average radius of ca. 0.8 nm to about 2 nm. To the best of our knowledge, this is the first demonstration of a continuous-flow SAXS setup for time-resolved studies of nanoparticle formation mechanisms that does not require the use of synchrotron facilities. In combination with X-ray absorption near edge structure microscopy, scanning electron microscopy, and UV-vis spectroscopy the obtained data allow the deduction of a two-step mechanism of gold nanoparticle formation. The first step is a rapid conversion of the ionic gold precursor into metallic gold nuclei, followed by particle growth via coalescence of smaller entities. Consequently it could be shown that the studied synthesis serves as a model system for growth driven only by coalescence processes.
KW - Nanoparticle formation mechanism
KW - SAXS
KW - Microstructured static mixer
KW - Continuous flow
PY - 2010
DO - https://doi.org/10.1021/nn901499c
SN - 1936-0851
VL - 4
IS - 2
SP - 1076
EP - 1082
PB - ACS Publ.
CY - Washington, DC, USA
AN - OPUS4-20940
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Herder, Martin
A1 - Erler, Robert
A1 - Rolf, Simone
A1 - Fischer, A.
A1 - Würth, Christian
A1 - Thünemann, Andreas
A1 - Kraehnert, R.
A1 - Emmerling, Franziska
T1 - Mechanistic insights into seeded growth processes of gold nanoparticles
N2 - A facile approach for the synthesis of monodisperse gold nanoparticles with radii in the range of 7 to 20 nm is presented. Starting from monodisperse seeds with radii of 7 nm, produced in the first step, the addition of a defined amount of additional precursor material permits distinct size regulation and the realization of predicted nanoparticle sizes. These information were derived from ex- and in situ investigations by comprehensive small angle X-ray scattering (SAXS), X-ray absorption near edge structure (XANES) and UV-Vis data to obtain information on the physicochemical mechanisms. The obtained mechanisms can be transferred to other seeded growth processes. Compared to similar approaches, the presented synthesis route circumvents the use of different reducing or stabilizing agents. The size of resulting nanoparticles can be varied over a large size range presented for the first time without a measurable change in the shape, polydispersity or surface chemistry. Thus, the resulting nanoparticles are ideal candidates for size dependence investigations.
KW - Gold nanoparticles
KW - SAXS
KW - XANES
KW - Growth mechanism
PY - 2010
DO - https://doi.org/10.1039/c0nr00541j
SN - 2040-3364
SN - 2040-3372
VL - 2
IS - 11
SP - 2463
EP - 2469
PB - RSC Publ.
CY - Cambridge
AN - OPUS4-22346
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Kraehnert, R.
A1 - Radtke, Martin
A1 - Reinholz, Uwe
A1 - Riesemeier, Heinrich
A1 - Thünemann, Andreas
A1 - Emmerling, Franziska
T1 - New insights of the nucleation and growth process of gold nanoparticles via in situ coupling of SAXS and XANES
N2 - Although metallic nanoparticles play an important role in the area of nanotechnology, a coherent mechanistic explanation for the evolution of the particles during their chemical synthesis has not yet been provided in many cases. To gain a profound understanding of the growth mechanism of colloidal nanoparticles, new approaches using Small Angle X-Ray Scattering (SAXS) combined with X-ray absorption near-edge structure (XANES) are presented. This combination allows for insights into two prominent syntheses routes of gold nanoparticles (GNP): The 'slow' reaction using sodium citrate (30-90 min) as a reducing agent and the 'fast' reaction employing NaBH4 (within few seconds). In the first case data derived with the coupled XANES and SAXS suggests a four-step particle formation mechanism. For the second system a time resolution in the order of 100-200 ms was achieved by coupling a common laboratory SAXS instrument with a microstructured mixer, which allows data acquisition in a continuous-flow mode. The results indicate a coalescence driven growth process. Based on the capabilities to deduce the size, number and polydispersity of the particles, the results of both methods enable the development of mechanistic schemes explaining the different phases of particle formation and growth, thus providing a basis for improved control over the synthesis processes.
KW - SAXS
KW - XANES
KW - Nanoparticle formation
PY - 2010
DO - https://doi.org/10.1088/1742-6596/247/1/012051
SN - 1742-6588
SN - 1742-6596
VL - 247
IS - 1
SP - 012051-1 - 012051-10
PB - IOP Publ.
CY - Bristol, UK
AN - OPUS4-22684
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Polte, Jörg
A1 - Tuaev, X.
A1 - Wuithschick, M.
A1 - Fischer, A.
A1 - Thünemann, Andreas
A1 - Rademann, K.
A1 - Kraehnert, R.
A1 - Emmerling, Franziska
T1 - Formation mechanism of colloidal silver nanoparticles: analogies and differences to the growth of gold nanoparticles
N2 - The formation mechanisms of silver nanoparticles using aqueous silver perchlorate solutions as precursors and sodium borohydride as reducing agent were investigated based on time-resolved in situ experiments. This contribution addresses two important issues in colloidal science: (i) differences and analogies between growth processes of different metals such as gold and silver and (ii) the influence of a steric stabilizing agent on the growth process. The results reveal that a growth due to coalescence is a fundamental growth principle if the monomer-supplying chemical reaction is faster than the actual particle formation.
KW - Silver nanoparticle growth
KW - Formation mechanisms
KW - Nucleation
KW - SAXS
PY - 2012
DO - https://doi.org/10.1021/nn301724z
SN - 1936-0851
VL - 6
IS - 7
SP - 5791
EP - 5802
PB - ACS Publ.
CY - Washington, DC, USA
AN - OPUS4-26427
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Purohit, Purv
A1 - Huacuja Sánchez, Jesús
A1 - Wang, D.-Y.
A1 - Emmerling, Franziska
A1 - Thünemann, Andreas
A1 - Heinrich, G.
A1 - Schönhals, Andreas
T1 - Structure - property relationships of nanocomposites based on polypropylene and layered double hydroxides
N2 - Nanocomposites based on polypropylene (PP) and organically modified ZnAl layered double hydroxides (ZnAl-LDH) were prepared by melt blending and investigated by a combination of differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SAXS and WAXS), and dielectric relaxation spectroscopy (DRS). An average number of stack size of LDH layers is calculated by analyzing the SAXS data which is close to that of pure organically modified ZnAl-LDH. Scanning microfocus SAXS investigations show that the ZnAl-LDH is homogeneously distributed in the PP matrix as stacks of 4–5 layers with an intercalated morphology. DSC and WAXS results show that the degree of crystallinity decreases linearly with the increasing content of LDH. The extrapolation of this dependence to zero estimates a limiting concentration of ca. 40% LDH where the crystallization of PP is completely suppressed by the nanofiller. The dielectric spectra of the nanocomposites show several relaxation processes which are discussed in detail. The intensity of the dynamic glass transition (β-relaxation) increases with the concentration of LDH. This is attributed to the increasing concentration of the exchanged anion dodecylbenzenesulfonate (SDBS) which is adsorbed at the LDH layers. Therefore, a detailed analysis of the β-relaxation provides information about the structure and the molecular dynamics in the interfacial region between the LDH layers and the polypropylene matrix which is otherwise dielectrically invisible (low dipole moment). As a main result, it is found that the glass transition temperature in this interfacial region is by 30 K lower than that of pure polypropylene. This is accompanied by a drastic change of the fragility parameter deduced from the relaxation map.
KW - Nanocomposites
KW - Layered double hydroxide
KW - Dielectric spectroscopy
KW - X-ray scattering
KW - Polypropylene
PY - 2011
DO - https://doi.org/10.1021/ma200323k
SN - 0024-9297
SN - 1520-5835
VL - 44
IS - 11
SP - 4342
EP - 4354
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-23921
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Purohit, Purv
A1 - Wang, D.-Y.
A1 - Emmerling, Franziska
A1 - Thünemann, Andreas
A1 - Heinrich, G.
A1 - Schönhals, Andreas
T1 - Arrangement of layered double hydroxide in a polyethylene matrix studied by a combination of complementary methods
N2 - Organically modified ZnAl Layered Double Hydroxides (ZnAl-LDH) was synthesized and melt blended with polyethylene to obtain nanocomposites. The resulting morphology was investigated by a combination of Differential Scanning Calorimetry (DSC), Small and Wide-angle X-ray scattering (SAXS and WAXS) and dielectric relaxation spectroscopy (DRS). The arrangement (intercalation) of polyethylene chains between LDH stacks was investigated employing SAXS. The homogeneity of the nanocomposites and average number of stack size (4–6 layers) were determined using scanning microfocus SAXS (BESSY II). DSC and WAXS results show that the degree of crystallinity decreases linearly with the increasing content of LDH. The extrapolation of this dependence to zero estimates a limiting concentration of ca. 45% LDH where the crystallization of PE is completely suppressed by the nanofiller. The dielectric spectra of the nanocomposites show several relaxation processes which are discussed in detail. The intensity of the dynamic glass transition (β-relaxation) increases with the concentration of LDH. This is attributed to the increasing concentration of the exchanged anion sodium dodecylbenzene sulfonate (SDBS) which is adsorbed at the LDH layers. Therefore, a detailed analysis of the β-relaxation provides information about the structure and the molecular dynamics in the interfacial region between the LDH layers and the polyethylene matrix which is otherwise dielectrically invisible (low dipole moment).
KW - Dielectric spectroscopy
KW - Polyethylene nanocomposites
KW - Layered double hydroxides
PY - 2012
DO - https://doi.org/10.1016/j.polymer.2012.03.041
SN - 0032-3861
SN - 1873-2291
VL - 53
IS - 11
SP - 2245
EP - 2254
PB - Springer
CY - Berlin
AN - OPUS4-25810
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pütz, E.
A1 - Smales, Glen Jacob
A1 - Jegel, O.
A1 - Emmerling, Franziska
A1 - Tremel, W.
T1 - Tuning ceria catalysts in aqueous media at the nanoscale: how do surface charge and surface defects determine peroxidase- and haloperoxidase-like reactivity
N2 - Designing the shape and size of catalyst particles, and their interfacial charge, at the nanometer scale can radically change their performance. We demonstrate this with ceria nanoparticles. In aqueous media, nanoceria is a functional mimic of haloperoxidases, a group of enzymes that oxidize organic substrates, or of peroxidases that can degrade reactive oxygen species (ROS) such as H2O2 by oxidizing an organic substrate. We show that the chemical activity of CeO2−x nanoparticles in haloperoxidase- and peroxidaselike reactions scales with their active surface area, their surface charge, given by the ζ-potential, and their surface defects (via the Ce3+/Ce4+ ratio). Haloperoxidase-like reactions are controlled through the ζ-potential as they involve the adsorption of charged halide anions to the CeO2 surface, whereas peroxidase-like reactions without charged substrates are controlled through the specific surface area SBET. Mesoporous CeO2−x particles, with large surface areas, were prepared via template-free hydrothermal reactions and characterized by small-angle X-ray scattering. Surface area, ζ-potential and the Ce3+/Ce4+ ratio are controlled in a simple and predictable manner by the synthesis time of the hydrothermal reaction as demonstrated by X-ray photoelectron spectroscopy, sorption and ζ-potential measurements. The surface area increased with synthesis time, whilst the Ce3+/Ce4+ ratio scales inversely with decreasing ζ-potential. In this way the catalytic activity of mesoporous CeO2−x particles could be tailored selectively for haloperoxidase- and peroxidase-like reactions. The ease of tuning the surface properties of mesoporous CeO2x particles by varying the synthesis time makes the synthesis a powerful general tool for the preparation of nanocatalysts according to individual needs.
KW - SAXS
KW - Ceria
KW - Zeta potential
PY - 2022
DO - https://doi.org/10.1039/D2NR03172H
SP - 1
EP - 12
PB - Royal Society of Chemistry
AN - OPUS4-55649
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Quiroz, J.
A1 - de Oliveira, P. F. M.
A1 - Shetty, S.
A1 - Oropeza, F.
A1 - Peña O’Shea, V.
A1 - Rodrigues, L.
A1 - Rodrigues, M.
A1 - Torresi, R.
A1 - Emmerling, Franziska
A1 - Camargo, P.
T1 - Bringing earth-abundant plasmonic catalysis to light: Gram-scale mechanochemical synthesis and tuning of activity by dual excitation of antenna and reactor sites
N2 - The localized surface plasmon resonance (LSPR) excitation in plasmonic nanoparticles (NPs) in the visible and near-infrared ranges is currently at the forefront of improving photocatalytic performances via plasmonic photocatalysis. One bottleneck of this field is that the NPs that often display the best optical properties in the visible and near-infrared ranges are based on expensive noble metals such as silver (Ag) and gold (Au). While earth-abundant plasmonic materials have been proposed together with catalytic metals in antenna–reactor systems, their performances remain limited by their optical properties. Importantly, the synthesis of plasmonic photocatalysts remains challenging in terms of scalability while often requiring several steps, high temperatures, and special conditions. Herein, we address these challenges by developing a one-pot, gram-scale, room-temperature synthesis of earth-abundant plasmonic photocatalysts while improving their activities beyond what has been dictated by the LSPR excitation of the plasmonic component. We describe the mechanochemical synthesis of earth-abundant plasmonic photocatalysts by using MoO3 (antenna) and Au (reactor) NPs as a proof-of-concept example and demonstrate that the dual plasmonic excitation of antenna and reactor sites enables the tuning of plasmonic photocatalytic performances toward the reductive coupling of nitrobenzene to azobenzene as a model reaction. In addition to providing a pathway to the facile and gram-scale synthesis of plasmonic photocatalysts, the results reported herein may open pathways to improved activities in plasmonic catalysis.
KW - MoO3
KW - Au nanoparticles
KW - Localized surface plasmon resonance
KW - Plasmonic photocatalysis
KW - Nitrobenzene reduction
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532089
DO - https://doi.org/10.1021/acssuschemeng.1c02063
VL - 9
IS - 29
SP - 9750
EP - 9760
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-53208
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Radunz, Sebastian
A1 - Kraus, Werner
A1 - Bischoff, F. A.
A1 - Emmerling, Franziska
A1 - Resch-Genger, Ute
A1 - Tschiche, Harald
T1 - Temperature- and Structure-Dependent Optical Properties and Photophysics of BODIPY Dyes
N2 - We report on the temperature- and structural-dependent optical properties and photophysics of a set of boron dipyrromethene (BODIPY) dyes with different substitution patterns of their meso-aryl subunit. Single-crystal Xray diffraction analysis of the compounds enabled a classification of the dyes into a sterically hindered and a unhindered group. The steric hindrance refers to a blocked rotational motion of the aryl subunit around the bond connecting this moiety to the meso-position of the BODIPY core. The energy barriers related to this rotation were simulated by DFT calculations. As follows from the relatively low rotational barrier calculated to about 17 kcal/mol, a free rotation is only possible for sterically unhindered compounds. Rotational barriers of more than 40 kcal/mol determined for the sterically hindered compounds suggest an effective freezing of the rotational motion in These molecules. With the aid of temperature-dependent spectroscopic measurements, we could show that the ability to rotate directly affects the optical properties of our set of BODIPY dyes. This accounts for the strong temperature dependence of the fluorescence of the sterically unhindered compounds which show a drastic decrease in fluorescence quantum yield and a significant shortening in fluorescence lifetime upon heating. The optical properties of the sterically hindered compounds, however, are barely affected by temperature. Our results suggest a nonradiative deactivation of the first excited singlet state of the sterically unhindered compounds caused by a conical intersection of the potential energy surfaces of the Ground and first excited state which is accessible by rotation of the meso-subunit. This is in good agreement with previously reported deactivation mechanisms. In addition, our results suggest the presence of a second nonradiative depopulation pathway of the first excited singlet state which is particularly relevant for the sterically hindered compounds.
KW - Fluorescence
KW - Sensor
KW - Switch
KW - pH
KW - BODIPY
KW - Dye
KW - Probe
KW - Synthesis
KW - Photophysics
KW - Mechanism
PY - 2020
DO - https://doi.org/10.1021/acs.jpca.9b11859
SN - 1089-5639
VL - 124
IS - 9
SP - 1787
EP - 1797
PB - American Chemical Society
AN - OPUS4-50639
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Akhmetova, Irina
A1 - Das, Chayanika
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Synthesis and In Situ Monitoring of Mechanochemical Preparation of Highly Proton Conductive Hydrogen-Bonded Metal Phosphonates
N2 - 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 a challenging bulk synthesis for real-world applications of these materials. Herein, we report the mechanochemical gram-scale synthesis of two isostructural metal hydrogen-bonded organic frameworks (MHOFs) of Co(II) and Ni(II) based on 1-hydroxyethylidenediphosphonic acid (HEDPH4) with 2,2′-bipyridine (2,2′-bipy): Co(HEDPH3)2(2,2′-bipy)·H2O (1) and Ni(HEDPH3)2(2,2′-bipy)·H2O (2). In situ monitoring of the mechanochemical synthesis using different synchrotron-based techniques revealed a one-step mechanism – the starting materials are directly converted to the product. With the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, both frameworks exhibited proton conduction in the range of 10–4 S cm–1 at room temperature under humid conditions. This study demonstrates the potential of green mechanosynthesis for bulk material preparation of framework-based solid-state proton conductors.
KW - Mechanochemistry
KW - Proton conductivity
KW - Metal Organic Frameworks
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577777
DO - https://doi.org/10.1021/acssuschemeng.2c07509
VL - 8
IS - 19
SP - 16687
EP - 16693
PB - ACS Publications
AN - OPUS4-57777
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Akhmetova, Irinia
A1 - Emmerling, Franziska
T1 - Mechanochemical and solution syntheses of two novel cocrystals of orcinol with two N,N0-Dipyridines: Structural diversity with varying ligand flexibility
N2 - We studied the influence of coformers flexibility on the supramolecular assembly of 5-substituted resorcinol. Two cocrystals of orcinol (ORL) with two dipyridine molecules, i.e. 1,2-di(4-pyridyl)ethane (ORLeBPE) and 1,2-di(4-pyridyl)ethylene (ORLeBPY), were prepared by mechanochemical synthesis and slow evaporation of solvent. The new crystalline solids were thoroughly characterized by single crystal Xray diffraction (SCXRD), powder X-ray diffraction analysis (PXRD), Fourier-transform infrared spectroscopy (FT-IR), differential thermal analysis (DTA), and thermogravimetric analysis (TGA). Structural determination reveals that in both cocrystals, the phenolepyridine, i.e. OeH/N(py) heterosynthon takes the main role in the formation of cocrystals. In ORLeBPE, the components form infinite 1D zig-zag chains, which are extended to 2D layer structure by inter-chain CeH/O interactions between BPE hydrogen atoms and hydroxyl oxygen atoms of ORL. In ORLeBPY, the components form a 0D fourcomponent complex. Formation of the discrete assemblies is attributed to the comparative rigid nature of BPY, which restricts the formation of an extended network.
KW - Cocrystal
KW - Single crystal
KW - X-ray diffraction
KW - Mechanochemistry
PY - 2020
DO - https://doi.org/10.1016/j.molstruc.2020.128303
SN - 0022-2860
VL - 1217
SP - 128303
PB - Elsevier B.V.
AN - OPUS4-51023
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Das, Chayanika
A1 - Emmerling, Franziska
T1 - Mechanochemical Synthesis of Phosphonate-Based Proton Conducting Metal-Organic Frameworks
N2 - Water-stable metal−organic frameworks (MOFs) with proton-conducting behavior have attracted great attention as promising materials for proton-exchange membrane fuel cells. Herein, we report the mechanochemical gram-scale synthesis of three new mixed-ligand phosphonate-based MOFs, {Co(H2PhDPA)(4,4′-bipy)H2O)·2H2O}n (BAM-1), {Fe(H2PhDPA)(4,4′-bipy) (H2O)·2H2O}n (BAM-2), and {Cu(H2PhDPA)(dpe)2(H2O)2·2H2O}n (BAM-3) [where H2PhDPA = phenylene diphosphonate, 4,4′-bipy = 4,4′-bipyridine, and dpe = 1,2-di(4-pyridyl)ethylene]. Single-crystal X-ray diffraction measurements revealed that BAM-1 and BAM-2 are isostructural and possess a three-dimensional (3D) network structure comprising one-dimensional (1D) channels filled with guest water molecules. Instead, BAM-3 displays a 1D network structure extended into a 3D supramolecular structure through hydrogenbonding and π−π interactions. In all three structures, guest water molecules are interconnected with the uncoordinated acidic hydroxyl groups of the phosphonate moieties and coordinated water molecules by means of extended hydrogen-bonding interactions. BAM-1 and BAM-2 showed a gradual increase in proton conductivity with increasing temperature and reached 4.9 × 10−5 and 4.4 × 10−5 S cm−1 at 90 °C and 98% relative humidity (RH). The highest proton conductivity recorded for BAM-3 was 1.4 × 10−5 S cm−1 at 50 °C and 98% RH. Upon further heating, BAM-3 undergoes dehydration followed by a phase transition to another crystalline form which largely affects its performance. All compounds exhibited a proton hopping (Grotthuss model) mechanism, as suggested by their low activation energy.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - Proton conductivity
PY - 2022
DO - https://doi.org/10.1021/acs.inorgchem.2c01023
VL - 61
SP - 10801
EP - 10809
PB - ACS Publications
AN - OPUS4-55448
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Witt, Julia
A1 - Jain, Mohit
A1 - Emmerling, Franziska
T1 - In situ time-resolved monitoring of mixed-ligand metal–organic framework mechanosynthesis
N2 - The mechanism of mixed-ligand metal–organic framework (MOF) formation, and the possible role of intermediate single-ligand metal complexes during mechanosynthesis, have not been explored yet. For the first time, we report here in situ real-time monitoring of the mechanochemical formation mechanism of mixed-ligand MOFs. Our results show that binary phases can act as intermediates or competing products in one-pot and stepwise synthesis.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - In situ X-ray diffraction
KW - Mixed-ligand MOFs
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558167
DO - https://doi.org/10.1039/D2CE00803C
SP - 1
EP - 4
PB - Royal Society of Chemistry
AN - OPUS4-55816
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Gernhard, M.
A1 - Radnik, Jörg
A1 - Witt, Julia
A1 - Roth, C.
A1 - Emmerling, Franziska
T1 - Mechanochemical synthesis of fluorine-containing Co-doped zeolitic imidazolate frameworks for producing electrocatalysts
N2 - Catalysts derived from pyrolysis of metal organic frameworks (MOFs) are promising candidates to replace expensive and scarce platinum-based electrocatalysts commonly used in polymer electrolyte membrane fuel cells. MOFs contain ordered connections between metal centers and organic ligands. They can be pyrolyzed into metal- and nitrogen-doped carbons, which show electrocatalytic activity toward the oxygen reduction reaction (ORR). Furthermore, metal-free heteroatom-doped carbons, such as N-F-Cs, are known for being active as well. Thus, a carbon material with Co-N-F doping could possibly be even more promising as ORR electrocatalyst. Herein, we report the mechanochemical synthesis of two polymorphs of a zeolitic imidazole framework, Co-doped zinc 2-trifluoromethyl-1H-imidazolate (Zn0.9Co0.1(CF3-Im)2). Time-resolved in situ X-ray diffraction studies of the mechanochemical formation revealed a direct conversion of starting materials to the products. Both polymorphs of Zn0.9Co0.1(CF3-Im)2 were pyrolyzed, yielding Co-N-F containing carbons, which are active toward electrochemical ORR.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - Nobel-metal free electrocatalysis
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546833
DO - https://doi.org/10.3389/fchem.2022.840758
SN - 2296-2646
VL - 10
IS - 840758
SP - 1
EP - 13
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-54683
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ravi, J.
A1 - Feiler, Torvid
A1 - Mondal, A.
A1 - Michalchuk, Adam
A1 - Reddy, C. M.
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Chandrasekar, R.
T1 - Plastically bendable organic crystals for monolithic and hybrid micro-optical circuits
N2 - Fluorescent plastically bendable crystals are a promising alternative to silicon-based materials for fabricating photonic integrated circuits, owing to their optical attributes and mechanical compliance. Mechanically bendable plastic organic crystals are rare. Their formation requires anisotropic intermolecular interactions and slip planes in the crystal lattice. This work presents three fluorescent plastically bendable crystalline materials namely, 2-((E)-(6-methylpyridin-2-ylimino)methyl)-4-chlorophenol (SB1), 2-((E)-(6-methylpyridin-2-ylimino)methyl)-4-bromophenol (SB2), and 2-((E)-(6-Bromopyridin-2-ylimino)methyl)-4-bromophenol (SB3) molecules. The crystal plasticity in response to mechanical stress facilitates the fabrication of various monolithic and hybrid (with a tip-to-tip coupling) photonic circuits using mechanical micromanipulation with an atomic force microscope cantilever tip. These plastically bendable crystals act as active (self-guiding of fluorescence) and passive waveguides both in straight and extremely bent (U-, J-, and O-shaped) geometries. These microcircuits use active and passive waveguiding principles and reabsorbance and energy-transfer mechanisms for their operation, allowing input-selective and direction-specific signal transduction.
KW - Flexible crystals
KW - Flexible waveguide
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565302
DO - https://doi.org/10.1002/adom.202201518
SN - 2195-1071
SP - 1
EP - 10
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-56530
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Riddell, N.
A1 - Becker, Roland
A1 - Chittim, B.
A1 - Emmerling, Franziska
A1 - Köppen, Robert
A1 - Lough, A.
A1 - McAlees, A.
A1 - McCrindle, R.
T1 - Preparation and X-ray structural characterization of further stereoisomers of 1,2,5,6,9,10-hexabromocyclododecane
N2 - Technical 1,2,5,6,9,10-hexabromocyclododecane (HBCD) consists largely of three diastereomers (α-, β-, and γ-HBCD) produced by the trans addition of bromine to cis,trans,trans-cyclododeca-1,5,9-triene (CDT). However, another seven diastereomers are theoretically possible and may be produced by trans addition of bromine across the double bonds of the other three isomers of 1,5,9-CDT. There are indications that small amounts of the minor HBCD isomers may be present in commercial HBCD mixtures or in products containing this brominated flame retardant (BFR). Such minor components may indeed derive from traces of other 1,5,9-CDTs in the cis, trans, trans starting material, however their formation may also be possible through isomerizations during the processing of this BFR or by bioisomerization subsequent to its release into the environment. Two of the seven additional diastereomers (δ- and ε-HBCD) were synthesized previously from trans,trans,trans-CDT. We now report the preparation of the remaining five diastereomers, ζ-, η-, and θ-HBCD from cis,cis,trans-CDT and ι- and κ-HBCD from cis,cis,cis-CDT, and their characterization by 1H NMR spectroscopy and X-ray crystallography. The availability of these further diastereomers of HBCD should aid in determining if the minor isomers are present in commercial samples of this BFR, in products containing HBCDs, or in environmental samples. We have also carried out an X-ray crystal structure determination on ε-HBCD, so that crystal structures are now available for all 10 HBCD diastereomers.
KW - Brominated flame retardants
KW - HBCDs
KW - Minor isomers
KW - X-ray
PY - 2011
DO - https://doi.org/10.1016/j.chemosphere.2011.06.014
SN - 0045-6535
SN - 0366-7111
VL - 84
IS - 7
SP - 900
EP - 907
PB - Elsevier Science
CY - Kidlington, Oxford
AN - OPUS4-24298
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Santos de Freitas, M.
A1 - Araghi, R. R.
A1 - Brandenburg, E.
A1 - Leiterer, Jork
A1 - Emmerling, Franziska
A1 - Folmert, K.
A1 - Gerling-Driessen, U. I. M.
A1 - Bardiaux, B.
A1 - Böttcher, C.
A1 - Pagel, K.
A1 - Diehl, A.
A1 - v. Berlepsch, H.
A1 - Oschkinat, H.
A1 - Koksch, B.
T1 - The protofilament architecture of a de novo designed coiled coil-based amyloidogenic peptide
N2 - Amyloid fibrils are polymers formed by proteins under specific conditions and in many cases they are related to pathogenesis, such as Parkinson’s and Alzheimer’s diseases. Their hallmark is the presence of a β-sheet structure. High resolution structural data on these systems as well as information gathered from multiple complementary analytical techniques is needed, from both a fundamental and a pharmaceutical perspective. Here, a previously reported de novo designed, pH-switchable coiled coil-based peptide that undergoes structural transitions resulting in fibril formation under physiological conditions has been exhaustively characterized by transmission electron microscopy (TEM), cryo-TEM, atomic force microscopy (AFM), wide-angle X-ray scattering (WAXS) and solid-state NMR (ssNMR). Overall, a unique 2-dimensional carpet-like assembly composed of large coexisiting ribbon-like, tubular and funnel-like structures with a clearly resolved protofilament substructure is observed. Whereas electron microscopy and scattering data point somewhat more to a hairpin model of β-fibrils, ssNMR data obtained from samples with selectively labelled peptides are in agreement with both, hairpin structures and linear arrangements.
KW - Amyloid
KW - Elektronenmikroskopie
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-458713
UR - https://www.sciencedirect.com/science/article/pii/S1047847718301333
DO - https://doi.org/10.1016/j.jsb.2018.05.009
SN - 1047-8477
VL - 203
IS - 3
SP - 263
EP - 272
PB - Elsevier
AN - OPUS4-45871
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sarfraz, Adnan
A1 - Schlegel, Moritz-Caspar
A1 - Wright, J.
A1 - Emmerling, Franziska
T1 - Advanced gas hydrate studies at ambient conditions using suspended droplets
N2 - We report the spontaneous formation of a clathrate hydrate in a suspended droplet at ambient conditions. A novel method for producing and stabilizing clathrates for analytical studies is described.
KW - Clathrates
KW - Thermography
KW - Acoustic levitator
KW - Dichloromethane
PY - 2011
DO - https://doi.org/10.1039/c1cc13049h
SN - 0022-4936
SN - 1359-7345
VL - 47
IS - 33
SP - 9369
EP - 9371
PB - Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-24480
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sarfraz, Adnan
A1 - Simo, A.
A1 - Fenger, R.
A1 - Christen, W.
A1 - Rademann, K.
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - Morphological diversity of caffeine on surfaces: needles and hexagons
N2 - A systematic crystal morphology study on the pharmaceutical model compound caffeine has been conducted on different surfaces: silicon, silver, soda lime glass, and silver subsurface ion-exchanged soda-lime silicate (SIMO) glasses. The morphology of the solid caffeine deposits has been investigated using environmental scanning electron microscopy (ESEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). Needle-shaped caffeine crystals have been observed by drop-casting and also by applying the rapid expansion of supercritical solutions (RESS) technique using supercritical carbon dioxide. The aspect ratio of the crystalline needles typically vary between 10 and 100, but have been observed as large as 500. The XRD data of the RESS products indicate unambiguously the presence of the thermodynamically most stable polymorph of caffeine known as the β-form. Under defined conditions we observe a unique, surface-mediated morphology for caffeine crystals with nearly perfect hexagonal shape. The relative fraction of the hexagons was seen to strongly increase especially when SIMO glasses were used. These hexagons have a distinct upper size limit depending on the solvent and substrate being used. The size distribution analysis of the hexagons yielded an average perimeter of typically 10 µm. The mechanism of the formation process of this new hexagonal motif is explained in terms of the spinodal dewetting of the thin film of caffeine solution on the surface.
KW - Caffeine
KW - Silicon
KW - Silver
KW - Ion exchanged soda lime silicate glass
KW - ESEM
KW - AFM
KW - X-ray diffraction
KW - RESS
KW - Carbon dioxide
KW - Supercritical fluids
PY - 2012
DO - https://doi.org/10.1021/cg101358q
SN - 1528-7483
VL - 12
IS - 2
SP - 583
EP - 588
PB - American Chemical Society
CY - Washington, DC, USA
AN - OPUS4-25457
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schenk, Jonas
A1 - Batzdorf, Lisa
A1 - Emmerling, Franziska
A1 - Kneipp, Janina
A1 - Panne, Ulrich
A1 - Buurman, Merwe
T1 - Simultaneous UV/Vis spectroscopy and surface enhanced raman scattering of nanoparticle formation and aggregation in levitated droplets
N2 - The formation and growth of hydroxylamine reduced silver nanoparticles were investigated by simultaneous Raman and UV/Vis spectroscopy coupled to an acoustic levitator as a sample holder. Based on the UV/Vis spectra, a two step particle formation mechanism with fast initial formation and adjacent coalescence can be proposed for the reduction of silver nitrate with hydroxylamine. The presence of the analyte adenine during particle formation resulted in differences in the adenine SERS signature compared to experiments, where adenine was added after particle synthesis. It was possible to monitor the adenine and sodium chloride induced aggregation of the nanoparticles and its dynamics based on both the extinction spectra and the SERS data. Correlating the information from the extinction spectra with the SERS intensity, the maximum SERS signals were observed at maximum extinction of the aggregated nanoparticle solution at the Raman excitation wavelength.
PY - 2012
DO - https://doi.org/10.1039/c2ay05744a
SN - 1759-9660
SN - 1759-9679
N1 - Geburtsname von Batzdorf, Lisa: Tröbs, L. - Birth name of Batzdorf, Lisa: Tröbs, L.
N1 - Geburtsname von Buurman, Merwe: Albrecht, M. - Birth name of Buurman, Merwe: Albrecht, M.
VL - 4
IS - 5
SP - 1252
EP - 1258
PB - RSC Publ.
CY - Cambridge
AN - OPUS4-25742
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scheurrell, Kerstin
A1 - B. Martins, Inês C.
A1 - Murray, Claire
A1 - Emmerling, Franziska
T1 - Exploring the role of solvent polarity in mechanochemical Knoevenagel condensation: in situ investigation and isolation of reaction intermediates
N2 - Mechanochemistry has proven to be a highly effective method for the synthesis of organic compounds. We studied the kinetics of the catalyst-free Knoevenagel reaction between 4-nitrobenzaldehyde and malononitrile, activated and driven by ball milling. The reaction was investigated in the absence of solvents (neat grinding) and in the presence of solvents with different polarities (liquid-assisted grinding). The reaction was monitored using time-resolved in situ Raman spectroscopy and powder X-ray diffraction (PXRD). Our results indicate a direct relationship between solvent polarity and reaction kinetics, with higher solvent polarity leading to faster product (2-(4-nitrobenzylidone)malononitrile) formation. For the first time, we were able to isolate and determine the structure of an intermediate 2-(hydroxy(4-nitrophenyl)methyl)malononitrile based on PXRD data.
KW - Physical and Theoretical Chemistry
KW - General Physics and Astronomy
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-588071
DO - https://doi.org/10.1039/D3CP02883F
SN - 1463-9076
VL - 25
IS - 35
SP - 23637
EP - 23644
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58807
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schiffmann, J.
A1 - Emmerling, Franziska
A1 - Martins, Ines
A1 - Van Wüllen, L.
T1 - In-situ reaction monitoring of a mechanochemical ball mill reaction with solid state NMR
N2 - We present an approach towards the in situ solid state NMR monitoring of mechanochemical reactions in a ball mill. A miniaturized vibration ball mill is integrated into the measuring coil of a home-built solid state NMR probe, allowing for static solid state NMR measurements during the mechanochemical reaction within the vessel. The setup allows to quantitatively follow the product evolution of a prototypical mechanochemical reaction, the formation of zinc phenylphosphonate from zinc acetate and phenylphosphonic acid. MAS NMR investigations on the final reaction mixture confirmed a reaction yield of 89% in a typical example. Thus, NMR spectroscopy may in the future provide complementary information about reaction mechanisms of mechanochemical reactions and team up with other analytical methods which have been employed to follow reactions in situ, such as Raman spectroscopy or X-ray diffraction.
KW - Mechanochemistry
KW - Solid state NMR
KW - NMR probe Development
PY - 2020
DO - https://doi.org/10.1016/j.ssnmr.2020.101687
VL - 109
SP - 101687
PB - Elsevier Inc.
AN - OPUS4-51283
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlegel, M.C.
A1 - Stroh, Julia
A1 - Malaga, K.
A1 - Meng, Birgit
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - Pathway of a damaging mechanism - Analyzing chloride attack by synchrotron based X-ray diffraction
N2 - Typically, the changes of the phase compositions due to the chemical attack are studied in-situ only by chemical analysis or microscopy. In this study, the chloride transport and binding in the cement matrix in different cementitious materials was analyzed by synchrotron based X-ray diffraction (SyXRD) and energy dispersive X-ray spectroscopy (EDX). Sample materials consisting of cement paste were embedded in high concentrated sodium chloride solution over different time spans. Afterwards, the phase and chemical compositions were determined. The high spatial resolution and the information about the chloride distribution offer a detailed view of chloride binding in the cement matrix and allow the conclusions about the degradation mechanisms. The results are discussed related to the influence of different supplementary cementitious materials on the damaging mechanism.
KW - Portland cement
KW - In-situ
KW - X-Ray diffraction
KW - EDX
KW - Durability
KW - Chloride attack
PY - 2015
DO - https://doi.org/10.1016/j.solidstatesciences.2015.03.021
SN - 1293-2558
SN - 1873-3085
VL - 44
SP - 45
EP - 54
PB - Elsevier Masson SAS
CY - Amsterdam
AN - OPUS4-33171
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlegel, Moritz-Caspar
A1 - Müller, Urs
A1 - Malaga, Katarina
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - Spatially resolved investigation of complex multi-phase systems using muXRF, SEM-EDX and high resolution SyXRD
N2 - Spatially resolved analysis of complex multi-phase systems can be validated through different analytical methods. This study compares investigations by scanning electron microscopy coupled with energy dispersive X-ray fluorescence analysis and high resolution X-ray diffraction. The studied sulfate attacked cement paste containing fly ashes consists of different interacting crystalline and amorphous phases. The complementary methods revealed in detail changes in phase composition due to the chemical attack. The advantages and disadvantages of both methods are discussed and suggestions are given for combining them with additional methods to maximize the information content.
KW - EDX-SEM
KW - SyXRD
KW - Spatial investigations
KW - Comparison
KW - High resolution
KW - Cement paste
KW - Sulfate attack
KW - Damaging mechanism
PY - 2013
DO - https://doi.org/10.1016/j.cemconcomp.2012.08.018
SN - 0958-9465
SN - 1873-393X
VL - 37
SP - 241
EP - 245
PB - Elsevier Ltd.
CY - Barking, Essex
AN - OPUS4-29111
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlegel, Moritz-Caspar
A1 - Müller, Urs
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - Deciphering the sulfate attack of cementitious materials by high-resolution micro-x-ray diffraction
N2 - The durability of cementitious materials depends, among others, on their resistance against chemical attack during the service life of a building. Here, we present an approach to analyze changes in the phase composition due to chemical attack in the form of sulfate ingress within the microstructure. Micro-X-ray (µX-ray) diffraction using synchrotron radiation in Debye–Scherrer (transmission) geometry allowed a spatial resolution of 10 µm. Phase transformations in the wake of damaging processes were observed in a detailed high-resolution imaging study. In comparison, samples containing supplementary cementitious materials were investigated and used to reconstruct the influence of different degeneration processes in detail. Additionally, reaction fronts within the bulk were localized by micro-X-ray fluorescence analysis. The experimental setup provided the possibility for analyzing the phase assemblage of a given sample without destroying the microstructure. The specimens for phase analysis are thick sections of the primary material and can be used for further microscopic analysis of the microstructure and microchemistry, e.g., scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDX) or Raman spectroscopy.
PY - 2011
DO - https://doi.org/10.1021/ac200181g
SN - 0003-2700
SN - 1520-6882
VL - 83
IS - 10
SP - 3744
EP - 3749
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-23669
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlegel, Moritz-Caspar
A1 - Sarfraz, Adnan
A1 - Müller, Urs
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - Erste Sekunden im Leben eines Bauwerks - In-situ-Synchrotron-Röntgenbeugungsuntersuchungen der Zementhydratation mit Millisekunden-Auflösung
N2 - Höchst dynamische Hydratationsprozesse in den ersten Sekunden bei der Entstehung eines Bauwerkes lassen sich mithilfe von Synchrotron-Röntgenbeugung mit einer sehr hohen Zeitauflösung nachverfolgen. Der Schwerpunkt lag dabei auf der Beeinflussung der Bildung erster kristalliner Hydratationsprodukte während des Frühstadiums der Zementhydratation.
KW - SyXRD
KW - High resolution
KW - In-situ
KW - Colloidal suspension
KW - Cement hydration
KW - In-situ-Analyse
KW - Kolloidale Suspensionen
KW - Röntgenbeugung
KW - Zementhydratation
PY - 2012
DO - https://doi.org/10.1002/ange.201200993
SN - 0044-8249
SN - 0932-2140
SN - 1521-3757
VL - 124
IS - 20
SP - 5078
EP - 5081
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-26284
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlegel, Moritz-Caspar
A1 - Sarfraz, Adnan
A1 - Müller, Urs
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - First seconds in a building's life - In situ synchrotron X-ray diffraction study of cement hydration on the millisecond timescale
N2 - Setting cement: Highly dynamic hydration processes that occur during the first seconds of cement hydration were studied by time-resolved synchrotron X-ray diffraction. Polycarboxylate ether additives were found to influence the formation of the initial crystalline hydration products on a molecular level.
KW - Cement hydration
KW - Colloidal suspensions
KW - In situ analysis
KW - X-ray diffraction
KW - SyXRD
KW - High resolution
KW - In-situ
PY - 2012
DO - https://doi.org/10.1002/anie.201200993
SN - 1433-7851
SN - 1521-3773
SN - 0570-0833
VL - 51
IS - 20
SP - 4993
EP - 4996
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-26287
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlegel, Moritz-Caspar
A1 - Wenzel, Klaus-Jürgen
A1 - Sarfraz, Adnan
A1 - Panne, Ulrich
A1 - Emmerling, Franziska
T1 - A wall-free climate unit for acoustic levitators
N2 - Acoustic levitation represents the physical background of trapping a sample in a standing acoustic wave with no contact to the wave generating device. For the last three decades, sample holders based on this effect have been commonly used for contact free handling of samples coupled with a number of analytical techniques. In this study, a wall-free climate unit is presented, which allows the control of the environmental conditions of suspended samples. The insulation is based on a continuous cold/hot gas flow around the sample and thus does not require any additional isolation material. This provides a direct access to the levitated sample and circumvents any influence of the climate unit material to the running analyses.
KW - Acoustic levition
PY - 2012
DO - https://doi.org/10.1063/1.4705968
SN - 0034-6748
SN - 1089-7623
VL - 83
IS - 5
SP - 055101-1 - 055101-3
PB - American Institute of Physics
CY - Melville, NY
AN - OPUS4-25881
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlögl, Johanna
A1 - Goldammer, Ole
A1 - Bader, Julia
A1 - Emmerling, Franziska
A1 - Riedel, Sebastian
T1 - Introducing AFS ([Al(SO3F)3]x) – a thermally stable, readily available, and catalytically active solid Lewis superacid
N2 - This paper introduces the thermally stable, solid Lewis superacid aluminium tris(fluorosulfate) (AFS), that is easy-to-synthesize from commercially available starting materials. Its applicability, e.g. in catalytic C–F bond activations, is shown.
KW - Lewis Acid
KW - C-F activation
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601001
DO - https://doi.org/10.1039/D4SC01753F
SN - 2041-6520
SP - 1
EP - 7
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60100
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scholz, G.
A1 - Emmerling, Franziska
A1 - Dreger, M.
A1 - Kemnitz, E.
T1 - Mechanochemical synthesis and characterization of hydrated and dehydrated crystalline strontium terephtalates
N2 - A successful mechanochemical synthesis of strontium terephthalate trihydrate is described for the first time. The dehydration of Sr(C8H4O4)·3H2O occurs at about 100 °C and results in a well-defined strontium terephtalate, Sr(C8H4O4), thermally stable up to 550 °C. Both compounds are not described so far in the literature. Their structures were solved by ab initio structure determination and subsequent Rietveld refinement of the powder diffraction data. Further methods like DTA-TG, MAS NMR and FT-IR spectroscopy, and BET measurements were used to characterize these compounds.
KW - Mechanochemical synthesis
KW - Ab initio structure determination
KW - MAS NMR spectroscopy
KW - Strontium
PY - 2013
DO - https://doi.org/10.1002/zaac.201200550
SN - 0044-2313
SN - 1521-3749
SN - 0372-7874
SN - 0863-1786
SN - 0863-1778
VL - 639
IS - 5
SP - 689
EP - 693
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-29117
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schulz, K.
A1 - Schmack, R.
A1 - Klemm, H. W.
A1 - Kabelitz, Anke
A1 - Schmidt, T.
A1 - Emmerling, Franziska
A1 - Kraehnert, R.
T1 - Mechanism and kinetics of hematite crystallization in air: Linking bulk and surface models via mesoporous films with defined nanostructure
N2 - Iron can form numerous oxides, hydroxides, and oxide−hydroxides. Despite their relevance, many of the transformation processes between these phases are still poorly understood. In particular the crystallization of quasi-amorphous hydroxides and oxide−hydroxides is difficult to assess, since typical diffraction and scattering methods provide only sampleaveraged information about the crystallized phases. We report a new approach for the investigation of the crystallization of oxide−hydroxides. The approach relies on model-type films that comprise a defined homogeneous nanostructure. The nanostructure allows quantitative linking of Information obtained by bulk-averaging diffraction techniques (XRD, SAXS) with locally resolved information, i.e., Domain sizes (SEM, TEM, LEEM) and phase composition (SAED). Using time-resolved imaging and diffraction we deduce mechanism and kinetics for the crystallization of ferrihydrite into hematite. Hematite forms via nucleation of hematite domains and subsequent Domain growth that terminates only upon complete transformation. A Johnson−Mehl−Avrami−Kolmogorov model describes the kinetics over a wide temperature range. The derived understanding enables the first synthesis of ferrihydrite films with ordered mesoporosity and quantitative control over the films’ hematite and ferrihydrite content.
KW - Iron oxide
KW - Crystallization
KW - Mesoporous films
KW - Nanostructure
PY - 2017
DO - https://doi.org/10.1021/acs.chemmater.6b05185
SN - 0897-4756
SN - 1520-5002
VL - 29
IS - 4
SP - 1724
EP - 1734
AN - OPUS4-39690
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Seidel, R.
A1 - Kraffert, K.
A1 - Kabelitz, Anke
A1 - Pohl, M.N.
A1 - Kraehnert, R.
A1 - Emmerling, Franziska
A1 - Winter, B.
T1 - Detection of the electronic structure of iron-(III)-oxo oligomers forming in aqueous solutions
N2 - The nature of the small iron-oxo oligomers in iron-(III) aqueous solutions has a determining effect on the chemical processes that govern the formation of nanoparticles in aqueous phase. Here we report on a liquid-Jet photoelectron-spectroscopy experiment for the investigation of the electronic structure of the occurring iron-oxo oligomers in FeCl3 aqueous solutions. The only iron species in the as-prepared 0.75 M solution are Fe3+ monomers. Addition of NaOH initiates Fe3+ hydrolysis which is followed by the formation of iron-oxo oligomers. At small enough NaOH concentrations, corresponding to approximately [OH]/[Fe] = 0.2–0.25 ratio, the iron oligomers can be stabilized for several hours without engaging in further aggregation. Here, we apply a combination of non-resonant as well as iron 2p and Oxygen 1s resonant photoelectron spectroscopy from a liquid microjet to detect the electronic structure of the occurring species. Specifically, the oxygen 1s partial electron yield X-ray absorption (PEY-XA) spectra are found to exhibit a peak well below the onset of liquid water and OH (aq) absorption. The iron 2p absorption gives rise to signal centered between the main absorption bands typical for aqueous Fe3+. Absorption bands in both PEY-XA spectra are found to correlate with an enhanced photoelectron Peak near 20 eV binding energy, which demonstrates the sensitivity of resonant photoelectron (RPE) spectroscopy to mixing between iron and ligand orbitals. These various signals from the iron-oxo oligomers exhibit Maximum intensity at [OH]/[Fe] = 0.25 ratio. For the same ratio, we observe changes in the pH as well as in complementary Raman spectra, which can be assigned to the Transition from monomeric to oligomeric species. At approximately [OH]/[Fe] = 0.3 we begin to observe particles larger than 1 nm in radius, detected by small-angle X-ray scattering.
KW - Iron-oxo oligomers
KW - XPS
KW - Electronic structure
PY - 2017
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-433468
DO - https://doi.org/10.1039/c7cp06945f
SN - 1463-9076
SN - 1463-9084
VL - 19
IS - 48
SP - 32226
EP - 32234
AN - OPUS4-43346
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Siegel, David
A1 - Blaske, Franziska
A1 - Koch, Matthias
A1 - Emmerling, Franziska
A1 - Nehls, Irene
T1 - Deacetyl tenuazonic acid p-toluenesulfonylhydrazone
KW - Deacetyl tenuazonic acid
KW - Toluenesulfonylhydrazine
KW - Hydrazone
KW - Crystal structure
PY - 2009
DO - https://doi.org/10.1107/S1600536809048958
SN - 1600-5368
VL - E65
IS - 12
SP - o3136 Sup-1 - o3136 Sup-8
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-20608
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Siegel, David
A1 - Koch, Matthias
A1 - Emmerling, Franziska
A1 - Nehls, Irene
T1 - Deacetyl tenuazonic acid
KW - Deacetyl tenuazonic acid
KW - X-ray single crystal diffraction
KW - Crystal structure
PY - 2009
DO - https://doi.org/10.1107/S1600536809015372
SN - 1600-5368
VL - 65
IS - 6
SP - o1201
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-19429
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Siegel, David
A1 - Merkel, Stefan
A1 - Koch, Matthias
A1 - Emmerling, Franziska
A1 - Nehls, Irene
T1 - 3-{1-[(2,4-Dinitrophenyl)hydrazino]ethylidene}-5-(1-methylpropyl)pyrrolidine-2,4-dione
KW - Tenuazonic acid 2,4-dinitrophenylhydrazone
KW - X-ray single crystal diffraction
KW - Crystal structure
PY - 2009
DO - https://doi.org/10.1107/S1600536809012458
SN - 1600-5368
VL - 65
IS - 5
SP - o988
EP - o989
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-19736
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Siegel, David
A1 - Troyanov, S.
A1 - Noack, J.
A1 - Emmerling, Franziska
A1 - Nehls, Irene
T1 - Alternariol
N2 - In the title compound (systematic name: 3,7,9-trihydroxy-1-methyl-6H-benzo[c]chromen-6-one), C14H10O5, the methyl group is shifted out of the molecular plane due to a steric collision, thus causing a slight twist of the benzene rings. The molecular structure is stabilized by an intramolecular O-H...O hydrogen bond, generating an S(6) ring. In the crystal, molecules are connected by intermolecular O-H...O hydrogen bonds into a three-dimensional network.
KW - Alternariol
KW - Kristallstruktur
PY - 2010
DO - https://doi.org/10.1107/S1600536810017502
SN - 1600-5368
VL - 66
IS - 6
SP - o1366
PB - Munksgaard
CY - Copenhagen
AN - OPUS4-21400
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simo, A.
A1 - Polte, Jörg
A1 - Pfänder, N.
A1 - Vainio, U.
A1 - Emmerling, Franziska
A1 - Rademann, K.
T1 - Formation mechanism of silver nanoparticles stabilized in glassy matrices
N2 - In any given matrix control over the final particle size distribution requires a constitutive understanding of the mechanisms and kinetics of the particle evolution. In this contribution we report on the formation mechanism of silver nanoparticles embedded in a soda-lime silicate glass matrix. For the silver ion-exchanged glass it is shown that at temperatures below 410 °C only molecular clusters (diameter <1 nm) are forming which are most likely silver dimers. These clusters grow to nanoparticles (diameter >1 nm) by annealing above this threshold temperature of 410 °C. It is evidenced that the growth and thus the final silver nanoparticle size are determined by matrix-assisted reduction mechanisms. As a consequence, particle growth proceeds after the initial formation of stable clusters by addition of silver monomers which diffuse from the glass matrix. This is in contrast to the widely accepted concept of particle growth in metal–glass systems, in which it is assumed that the nanoparticle formation is predominantly governed by Ostwald ripening processes.
PY - 2012
DO - https://doi.org/10.1021/ja309034n
SN - 0002-7863
SN - 1520-5126
VL - 134
IS - 45
SP - 18824
EP - 18833
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-27539
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simoes, R.
A1 - Bernades, C.
A1 - Joseph, A.
A1 - Piedade, F.
A1 - Kraus, Werner
A1 - Emmerling, Franziska
A1 - Diogo, H.
A1 - da Piedade, M.
T1 - Polymorphism in simvastatin: Twinning, disorder, and enantiotropic phase transitions
N2 - : Simvastatin is one of the most widely used active pharmaceutical ingredients for the treatment of hyperlipidemias. Because the compound is employed as a solid in drug formulations, particular attention should be given to the characterization of different polymorphs, their stability domains, and the nature of the phase transitions that relate them. In this work, the phase transitions delimiting the stability domains of three previously reported simvastatin forms were investigated from structural, energetics, and dynamical points of view based on single crystal X-ray diffraction (SCXRD), hot stage microscopy (HSM), and differential scanning calorimetry (DSC) experiments (conventional scans and heat capacity measurements), complemented with molecular dynamics (MD) simulations. Previous assignments of the crystal forms were confirmed by SCXRD: forms I and II were found to be orthorhombic (P212121, Z′/Z = 1/4) and form III was monoclinic (P21, Z′/Z = 2/4). The obtained results further indicated that (i) the transitions between different forms are observed at 235.9 ± 0.1 K (form III → form II) and at 275.2 ± 0.2 K (form II → form I) in DSC runs carried out at 10 K min−1 and close to these values when other types of techniques are used (e.g., HSM). (ii) They are enantiotropic (i.e., there is a transition temperature relating the two phases before fusion at which the stability order is reversed), fast, reversible, with very little hysteresis between heating and cooling modes, and occur under single crystal to single crystal conditions. (iii) A nucleation and growth mechanism seems to be followed since HSM experiments on single crystals evidenced the propagation of an interface, accompanied by a change of birefringence and crystal contraction or expansion (more subtle in the case of form III → form II), when the phase transitions are triggered. (iv) Consistent with the reversible and small hysteresis nature of the phase transitions, the SCXRD results indicated that the molecular packing is very similar in all forms and the main structural differences are associated with conformational changes of the “ester tail”. (v) The MD simulations further suggested that the tail is essentially “frozen” in two conformations below the III → II transition temperature, becomes progressively less hindered throughout the stability domain of form II, and acquires a large conformational freedom above the II → I transition. Finally, the fact that these transitions were found to be fast and reversible suggests that polymorphism is unlikely to be a problem for pharmaceutical formulations employing crystalline simvastatin because, if present, the III and II forms will readily convert to form I at ambient temperature.
KW - Polymorphism
KW - Twinning
KW - Disorder
KW - Simvastatine
PY - 2018
DO - https://doi.org/10.1021/acs.molpharmaceut.8b00818
SN - 1543-8384
SN - 1543-8392
VL - 15
IS - 11
SP - 5349
EP - 5360
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-46927
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simões, R. G.
A1 - Melo, P. L. T.
A1 - Bernardes, C. E. S.
A1 - Heilmann, Maria
A1 - Emmerling, Franziska
A1 - Minas da Piedade, M. E.
T1 - Linking Aggregation in Solution, Solvation, and Solubility of Simvastatin: An Experimental and MD Simulation Study
N2 - The solubility is generally thought to be higher if the solvent effectively solvates solute molecules that are well-separated from each other. The present work suggests, however, that the formation of large solute aggregates does not necessarily imply less effective solvation and lower solubility. Measurements of the solubility of simvastatin (one of the most commonly prescribed antihyperlipidemic drugs) in three solvents with different polarities and protic characters, led to the solubility order acetone > ethyl acetate > ethanol, in the full temperature range covered by the experiments (283–308 K). An analysis of the structures of the different solutions on the basis of molecular dynamics simulation results indicated that this trend seems to be determined by a balance between the solute tendency toward aggregation and the ability of the solvent to efficiently solvate it, by integrating the cluster structures, regardless of their size, and effectively establishing solvent–solute interactions.
KW - Simvastatin
KW - Solubility
KW - API
KW - Aggregation
PY - 2021
DO - https://doi.org/10.1021/acs.cgd.0c01325
VL - 21
IS - 1
SP - 544
EP - 551
AN - OPUS4-52185
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sobina, E.
A1 - Zimathies, Annett
A1 - Prinz, Carsten
A1 - Emmerling, Franziska
A1 - de Santis Neves, R.
A1 - Wang, H.
A1 - Mizuno, K.
A1 - Devoille, L.
A1 - Steel, E.
A1 - Ceyhan, A.
A1 - Sadak, E.
ED - Sobina, E.
T1 - Final report of CCQM-K153 Measurement of Specific Adsorption A [mol/kg] of N-2 and Kr on nonporous SiO2 at LN temperature (to enable a traceable determination of the Specific Surface Area (BET) following ISO 9277)
N2 - CCQM key comparison K-153 Measurement of Specific Adsorption A [mol/kg] of N-2 and Kr on nonporous SiO2 at LN temperature (to enable a traceable determination of the Specific Surface Area (BET) following ISO 9277) has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The objective of this key comparison is to compare the equivalency of the National Metrology Institutes (NMIs) and Designated Institutes (DIs) for the measurement of specific adsorption, BET specific surface area) of nonporous substances (sorbents, ceramics, catalytic agents, etc) used in advanced technology.
In this key comparison, a commercial nonporous silicon dioxide was supplied as a sample. Eight NMIs participated in this key comparison, but only five NMI's have reported in time. All participants used a gas adsorption method, here nitrogen and (or) krypton adsorption at 77.3 K, for analysis according to the international standards ISO 15901-2 and 9277.
In this key comparison, the degrees of equivalence uncertainties for specific adsorption nitrogen and krypton, BET specific surface area were established.
KW - Nonporous SiO2
KW - Specific Adsorption of N-2 and Kr
KW - BET specific surface area
PY - 2019
DO - https://doi.org/10.1088/0026-1394/56/1A/08013
VL - 56
IS - 1A
SP - 08013
PB - IOP publishing Ltd
CY - Bristol, UK
AN - OPUS4-50358
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 - Sobisch, T.
A1 - Emmerling, Franziska
A1 - Girod, Matthias
A1 - Menzel, Michael
A1 - Lerche, D.
T1 - Advantages of dual wavelength detection for size determination of nanoparticles with analytical centrifugation
KW - Particle size distributions
KW - Dual wavelength detection
KW - Analytical centrifugation
KW - Nanoparticle separation
PY - 2013
SN - 978-3-944261-28-7
SN - 978-3-944261-36-2
SN - 978-3-944261-52-2
VL - 4
SP - 9
EP - 11
AN - OPUS4-30802
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Som, T.
A1 - Simo, A.
A1 - Fenger, R.
A1 - Troppenz, G.V.
A1 - Bansen, R.
A1 - Pfänder, N.
A1 - Emmerling, Franziska
A1 - Rappich, J.
A1 - Boeck, T.
A1 - Rademann, K.
T1 - Bismuth hexagons: facile mass synthesis, stability and applications
N2 - A unique direct electrodeposition technique involving very high current densities, high voltages and high electrolyte concentrations is applied for highly selective mass synthesis of stable, isolable, surfactant-free, single-crystalline Bi hexagons on a Cu wire at room temperature. A formation mechanism of the hexagons is proposed. The morphology, phase purity, and crystallinity of the material are well characterized by FESEM, AFM, TEM, SAED, EDX, XRD, and Raman spectroscopy. The thermal stability of the material under intense electron beam and intense laser light irradiation is studied. The chemical stability of elemental Bi in nitric acid shows different dissolution rates for different morphologies. This effect enables a second way for the selective fabrication of Bi hexagons. Bi hexagons can be oxidized exclusively to α-Bi2O3 hexagons. The Bi hexagons are found to be promising for thermoelectric applications. They are also catalytically active, inducing the reduction of 4-nitrophenol to 4-aminophenol. This electrodeposition methodology has also been demonstrated to be applicable for synthesis of bismuth-based bimetallic hybrid composites for advanced applications.
KW - Bismuth
KW - Hexagons
KW - Dendrites
KW - Single-crystal
KW - Thermoelectric applications
KW - Catalytic applications
PY - 2012
DO - https://doi.org/10.1002/cphc.201101009
SN - 1439-4235
VL - 13
IS - 8
SP - 2162
EP - 2169
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-26278
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Som, Tirtha
A1 - Troppenz, G.V.
A1 - Wendt, R. R.
A1 - Wollgarten, M.
A1 - Rappich, J.
A1 - Emmerling, Franziska
A1 - Rademann, Klaus
T1 - Graphene oxide/alpha-Bi2O3 composites for visible-light photocatalysis, chemical catalysis, and solar energy conversion
N2 - The growing challenges of environmental purification by solar photocatalysis, precious-metal-free catalysis, and photocurrent generation in photovoltaic cells receive the utmost global attention. Here we demonstrate a one-pot, green chemical synthesis of a new stable heterostructured, ecofriendly, multifunctional microcomposite that consists of α-Bi2O3 microneedles intercalated with anchored graphene oxide (GO) microsheets (1.0 wt?%) for the above-mentioned applications on a large economical scale. The bare α-Bi2O3 microneedles display two times better photocatalytic activities than commercial TiO2 (Degussa-P25), whereas the GO-hybridized composite exhibits approximately four to six times enhanced photocatalytic activities than the neat TiO2 photocatalyst in the degradation of colored aromatic organic dyes (crystal violet and rhodamine 6G) under visible-light irradiation (300 W tungsten lamp). The highly efficient activity is associated with the strong surface adsorption ability of GO for aromatic dye molecules, the high carrier acceptability, and the efficient electron–hole pair separation in Bi2O3 by individual adjoining GO sheets. The introduction of Ag nanoparticles (2.0 wt?%) further enhances the photocatalytic performance of the composite over eightfold because of a plasmon-induced electron-transfer process from Ag nanoparticles through the GO sheets into the conduction band of Bi2O3. The new composites are also catalytically active and catalyze the reduction of 4-nitrophenol to 4-aminophenol in the presence of borohydride ions. Photoanodes assembled from GO/α-Bi2O3 and Ag/GO/α-Bi2O3 composites display an improved photocurrent response (power conversion efficiency ~20?% higher) over those prepared without GO in dye-sensitized solar cells.
KW - Bismuth
KW - Dyes/pigments
KW - Environmental chemistry
KW - Graphene
KW - Photochemistry
PY - 2014
DO - https://doi.org/10.1002/cssc.201300990
SN - 1864-5631
SN - 1864-564X
VL - 7
IS - 3
SP - 854
EP - 865
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-30390
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Somasundaram, S. K.
A1 - Buzanich, Ana
A1 - Emmerling, Franziska
A1 - Krishnan, S.
A1 - Senthilkumar, K.
A1 - Joseyphus, R.J.
T1 - New insights into pertinent Fe-complexes for the synthesis of iron via the instant polyol process
N2 - Chemically synthesized iron is in demand for biomedical applications due to its large saturation magnetization compared to iron oxides. The polyol process, suitable for obtaining Co and Ni particles and their alloys, is laborious in synthesizing Fe. The reaction yields iron oxides, and the reaction pathway remains unexplored. This study shows that a vicinal polyol, such as 1,2-propanediol, is suitable for obtaining Fe rather than 1,3-propanediol owing to the formation of a reducible Fe intermediate complex. X-ray absorption spectroscopy analysis reveals the ferric octahedral geometry and tetrahedral geometry in the ferrous state of the reaction intermediates in 1,2-propanediol and 1,3-propanediol, respectively. The final product obtained using a vicinal polyol is Fe with a γ-Fe2O3 shell, while the terminal polyol is favourable for Fe3O4. The distinct Fe–Fe and Fe–O bond lengths suggest the presence of a carboxylate group and a terminal alkoxide ligand in the intermediate of 1,2-propanediol. A large Fe–Fe bond distance suggests diiron complexes with bidentate carboxylate bridges. Prominent high-spin and low-spin states indicate the possibility of transition, which favors the reduction of iron ions in the reaction using 1,2-propanediol.
KW - XAS
KW - Nanoparticle
PY - 2023
DO - https://doi.org/10.1039/D3CP01969A
SN - 1463-9076
VL - 25
IS - 33
SP - 21970
EP - 21980
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58073
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Souza, B.
A1 - Chauque, S.
A1 - de Oliveira, P.
A1 - Emmerling, Franziska
A1 - Torresi, R.
T1 - Mechanochemical optimization of ZIF-8/Carbon/S8 composites for lithium-sulfur batteries positive electrodes
N2 - The application of lithium-sulfur (Li-S) batteries is still limited by their rapid capacity fading. The pulverization of the sulfur positive electrode after the lithiation and the consequence dissolution of long chain polysulfides in organic solvents lead to the shuttle effect. To address these issues, here we report the mechanochemical preparation of ZIF-8 (Zeolitic Imidazole Framework-8)-based composites as sulfur hosts for positive electrodes in Li-S batteries. We studied different methods for the incorporation of conductive carbon. Also, the replacement of Zn2+ metal centers by other bivalent metals (Cu2+, Co2+ and Ni2+), enabled the preparation of other ZIF-8-based materials. The positive electrode ZIF-8/C/S8 showed initial discharges of 772 mA h g−1 while the pristine one, ZIF-8/S8, displayed 502 mA h g−1. The enhanced performance of 54% for ZIF-8/C/S8 indicates that the direct mechanochemical synthesis of ZIF-8 with conductive carbon is beneficial at initials charge/discharge process in comparison to traditional slurry preparation (ZIF-8/S8). Also, the Li2S6 absorption tests shows 87% of discoloration with ZIF-8/C/S8, confirming the better polysulfides absorption.
KW - Lithium-sulfur battery
KW - Metal organic frameworks
KW - ZIF-8
KW - Mechanochemistry
PY - 2021
DO - https://doi.org/10.1016/j.jelechem.2021.115459
VL - 896
SP - 115459
PB - Elsevier B.V.
AN - OPUS4-53542
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stawski, Tomasz
A1 - Karafiludis, Stephanos
A1 - Pimentel, Carlos
A1 - Montes-Hernández, German
A1 - Kochovski, Zdravko
A1 - Bienert, Ralf
A1 - Weimann, Karin
A1 - Emmerling, Franziska
A1 - Scoppola, Ernesto
A1 - Van Driessche, Alexander E.S.
T1 - Solution-driven processing of calcium sulfate: The mechanism of the reversible transformation of gypsum to bassanite in brines
N2 - Here, we show that calcium sulfate dihydrate (gypsum) can be directly, rapidly and reversibly converted to calcium sulfate hemihydrate (bassanite) in high salinity solutions (brines). The optimum conditions for the efficient production of bassanite in a short time (<5 min) involve the use of brines with c(NaCl) > 4 M and maintaining a temperature, T > 80 °C. When the solution containing bassanite crystals is cooled down to around room temperature, eventually gypsum is formed. When the temperature is raised again to T > 80 °C, bassanite is rapidly re-precipitated. This contrasts with the better-known behaviour of the bassanite phase in low-salt environments. In low-salinity aqueous solutions, bassanite is considered to be metastable with respect to gypsum and anhydrite, and therefore gypsum-to-bassanite conversion does not occur in pure water. Interestingly, the high-salinity transformation of gypsum-to-bassanite has been reported by many authors and used in practice for several decades, although its very occurrence actually contradicts numerical thermodynamic predictions regarding solubility of calcium sulfate phases. By following the evolution of crystalline phases with in situ and time-resolved X-ray diffraction/scattering and Raman spectroscopy, we demonstrated that the phase stability in brines at elevated temperatures was inaccurately represented in the thermodynamic databases. Most notably for c(NaCl) > 4 M, and T > 80 °C gypsum becomes readily more soluble than bassanite, which induces the direct precipitation of the latter from gypsum. The fact that these transformations are controlled by the solution provides extensive opportunities for precise manipulation of crystal formation. Our experiments confirmed that bassanite remained the sole crystalline phase for many hours before reverting into gypsum. This property is extremely advantageous for practical processing and efficient crystal extraction in industrial scenarios.
KW - Industrial and Manufacturing Engineering
KW - Strategy and Management
KW - General Environmental Science
KW - Renewable Energy, Sustainability and the Environment
KW - Building and Construction
KW - Calcium sulfate
KW - Gypsum
KW - Bassanite
KW - Scattering
KW - Raman
KW - In situ
KW - Synchrotron
KW - BESSY
KW - MySpot
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594698
UR - https://www.sciencedirect.com/science/article/pii/S0959652624004591#appsec1
DO - https://doi.org/10.1016/j.jclepro.2024.141012
SN - 0959-6526
VL - 440
SP - 1
EP - 12
PB - Elsevier B.V.
AN - OPUS4-59469
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stawski, Tomasz
A1 - Smales, Glen Jacob
A1 - Scoppola, E.
A1 - Jha, D.
A1 - Morales, L. F. G.
A1 - Moya, A.
A1 - Wirth, R.
A1 - Pauw, Brian Richard
A1 - Emmerling, Franziska
A1 - Van Driessche, A. E. S.
T1 - Seeds of imperfection rule the mesocrystalline disorder in natural anhydrite single crystals
N2 - In recent years, we have come to appreciate the astounding intricacies associated with the formation of minerals from ions in aqueous solutions. In this context, a number of studies have revealed that the nucleation of calcium sulfate systems occurs nonclassically, involving the aggregation and reorganization of nanosized prenucleation species. In recent work, we have shown that this particle-mediated nucleation pathway is actually imprinted in the resultant micrometer-sized CaSO4 crystals. This property of CaSO4 minerals provides us with the unique opportunity to search for evidence of nonclassical nucleation pathways in geological environments.
In particular, we focused on large anhydrite Crystals extracted from the Naica Mine in Mexico. We were able to shed light on this mineral's growth history by mapping defects at different length scales. Based on this, we argue that the nanoscale misalignment of the structural subunits, observed in the initial calcium sulfate crystal seeds, propagates through different length scales both in morphological, as well as in strictly crystallographic aspects, eventually causing the formation of large mesostructured single crystals of anhydrite. Hence, the nonclassical nucleation mechanism introduces a “seed of imperfection,” which leads to a macroscopic “single” crystal whose fragments do not fit together at different length scales in a self-similar manner. Consequently, anisotropic voids of various sizes are formed with very welldefined walls/edges. However, at the same time, the material retains in part its single crystal nature.
KW - Calcium sulfate
KW - Anhydrite
KW - Mesocrystal
KW - Nucleation
KW - Naica
PY - 2021
DO - https://doi.org/10.1073/pnas.2111213118
SN - 0027-8424
VL - 118
IS - 48
SP - 1
EP - 11
PB - National Academy of Sciences (USA)
CY - Washington
AN - OPUS4-53820
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stephan, H.
A1 - Kubeil, M.
A1 - Emmerling, Franziska
A1 - Müller, C.E.
T1 - Polyoxometalates as versatile enzyme inhibitors
N2 - Polyoxometalates (POMs) are inorganic cluster compounds that have been shown to possess a number of pharmacological properties, including antidiabetic, antibacterial, antiprotozoal, antiviral and anticancer activities. Their molecular mechanism of action is largely unknown. However, several studies indicate that many of their activities may be due to the inhibition of enzymes, in particular, of those enzymes that are accessible from the extracellular space and do not require the penetration of cell membranes. In this review, we describe the recent progress in the preparation and optimization of POMs, and an evaluation of their use as inhibitors of different families of enzymes. The next important steps in this area of research will be to gain a better understanding of the interactions of POMs with enzymes on a structural level through an X-ray crystallographic study of enzyme–POM complexes and the analysis of structure–activity relationships. Furthermore, POMs with increased stability and in vivo half-lives have to be prepared. Surface modification may allow the targeting of POM drugs at their sites of action.
KW - Cluster compounds
KW - Polyoxometalates
KW - Metalloprotein mimics
KW - Enzymes
KW - Inhibitors
KW - Bioinorganic chemistry
PY - 2013
DO - https://doi.org/10.1002/ejic.201201224
SN - 1434-1948
SN - 1099-0682
VL - 2013
IS - 10-11
SP - 1585
EP - 1594
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-28076
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stroh, Julia
A1 - Ali, Naveed Zafar
A1 - Maierhofer, Christiane
A1 - Emmerling, Franziska
T1 - Ettringite via Mechanochemistry: A Green and Rapid Approach for Industrial Application
N2 - Here, we report on a first mechanochemical synthesis of ettringite, an important cement hydrate phase. The mineral compound ettringite ([Ca3Al(OH)6]2·(SO4)3·26H2O) occurs rarely in nature, but is common for cement-based materials. Ettringite has wide technical application in the ceramic and paper industry. However, its typical wet-chemical synthesis is cumbersome and produces waste water and CO2 emissions. Here, we investigate the first mechanochemical synthesis of ettringite for developing an easy and sustainable alternative for industrial application. The mechanosynthesis was monitored in situ by coupled synchrotron X-ray diffraction (XRD) and infrared thermography (IRT). The consumption of the reactants and the formation of the reaction product were monitored with time-resolved XRD. IRT showed the temperature increase based on the exothermic reaction. The reaction conversion was significantly improved changing the strategy of the mechanosynthesis from a one- to a two-step process. The latter included neat pregrinding of solid reactants followed by a delayed addition of the stoichiometric amount of water. Thus, an increase of reaction conversion from 34 to 94% of ettringite could be achieved.
KW - XRD
KW - Mechanochemistry
KW - Ettringite
KW - In situ
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-479016
DO - https://doi.org/10.1021/acsomega.9b00560
SN - 2470-1343
VL - 4
IS - 4
SP - 7734
EP - 7737
PB - ACS Publications
CY - Washington, DC
AN - OPUS4-47901
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stroh, Julia
A1 - Feiler, Torvid
A1 - Ali, N. Z.
A1 - Minas da Piedade, M. E.
A1 - Emmerling, Franziska
T1 - Mechanistic Insights into a Sustainable Mechanochemical Synthesis of Ettringite
N2 - Mechanochemistry offers an environmentally benign and facile synthesis method for a variety of cement paste constituents. In addition, these methods can be used to selectively tune the properties of cement components. The mineral ettringite is an important component of cementitious materials and has additional technological potential due to its ion exchange properties.
Synthesis of ettringite via mechanochemistry is an environmentally friendly alternative to conventional wet-chemical synthesis established in industry. This contribution explores the mechanism of a two-step mechanochemical synthesis of ettringite, which was previously found to greatly improve the reaction conversion as compared with one-pot synthesis. The crystallinity of Al(OH)3 was found to decrease during the first stage of this mechanochemical synthesis. This was correlated to a significant decrease in the particle size of Al(OH)3 in this stage. No other significant changes were found for the other components, suggesting that mechanochemical activation of Al(OH)3 is responsible for the enhanced formation of ettringite by the two-step approach. The environmentally friendly approach developed for ettringite synthesis offers a versatile synthetic strategy, which can be applied to synthesise further cementitious materials.
KW - Ettringite
KW - Mechanochemistry
KW - Sustainability
KW - X-ray diffraction
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-489172
DO - https://doi.org/10.1002/open.201900215
VL - 8
IS - 7
SP - 1012
EP - 1019
PB - ChemPubSoc
AN - OPUS4-48917
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stroh, Julia
A1 - Meng, Birgit
A1 - Emmerling, Franziska
T1 - Deterioration of hardened cement paste under combined sulphatechloride attack investigated by synchrotron XRD
N2 - The exact mechanisms of the phase transitions caused by a combined sulphate-chloride attack are discussed controversially. The main points concern the mutual influences of sulphate and chloride ions during the secondary binding processes of these anions within cement hydrate phases. We simulated combined sulphate-chloride attack under laboratory conditions using solutions containing NaCl and Na2SO4 in different concentrations. Three sample compositions were used for the preparation of the specimens. In two of them, 30% of Portland cement was replaced by supplementary cementitious materials (fly ash, slag). The phase distribution in the samples was determined using synchrotron X-ray diffraction. The analysis with high spatial resolution allows the localisation of the secondary phase formation in the microstructural profile of the sample. A mechanism of the phase developments under combined sulphate-chloride attack is derived.
KW - Cement paste
KW - Sulphate-chloride attack
KW - Portland cement
KW - Mineral additions
PY - 2016
DO - https://doi.org/10.1016/j.solidstatesciences.2016.04.002
IS - 56
SP - 29
EP - 44
PB - Elsevier Masson SAS
CY - Issy les Moulineaux cedex; France
AN - OPUS4-35936
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stroh, Julia
A1 - Meng, Birgit
A1 - Emmerling, Franziska
T1 - Monitoring of sulphate attack on hardened cement paste studied by synchrotron XRD
N2 - The complex matter of external sulphate attack on cement-based construction materials is still not completely understood. The concentration of sulphate is a crucial factor for the formation of secondary phases and phase transitions of cement hydrates due to sulphate ingress into the microstructure. The sulphate attack on building materials for high and low sulphate concentrations was monitored by laboratory experiments. Hardened cement paste consisting of ordinary Portland cement (CEM I) were exposed to aqueous solutions of sodium sulphate for 18 months. Three sample compositions were used for this research, including different supplementary cementitious materials (SCM). The phase composition was determined for different time spans by high resolution synchrotron X-ray diffraction. Cross sections of exposed cement prisms were investigated as a representation of the microstructural profile. Based on the data, a temporal and spatial determination of the stages of the sulphate attack and the deterioration course was possible. Cement matrices blended with slag showed the highest resistance against sulphate attack.
KW - Cement paste
KW - Sulphate attack
KW - Mineral additions
KW - Concentration
KW - Monitoring
PY - 2015
DO - https://doi.org/10.1016/j.solidstatesciences.2015.08.006
SN - 1293-2558
SN - 1873-3085
VL - 48
SP - 278
EP - 285
PB - Elsevier Masson SAS
CY - Amsterdam
AN - OPUS4-34281
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stroh, Julia
A1 - Schlegel, Moritz-Caspar
A1 - Irassar, E.F.
A1 - Meng, Birgit
A1 - Emmerling, Franziska
T1 - Applying high resolution SyXRD analysis on sulfate attacked concrete field samples
N2 - High resolution synchrotron X-ray diffraction (SyXRD) was applied for a microstructural profile analysis of concrete deterioration after sulfate attack. The cement matrices consist of ordinary Portland cement and different amounts of supplementary cementitious materials, such as fly ash, natural pozzolana and granulated blast furnace slag. The changes of the phase composition were determined along the direction of sulfate ingress. This approach allows the identification of reaction fronts and zones of different phase compositions and conclusions about the mechanisms of sulfate attack. Two reaction fronts were localized in the initial 4 mm from the sample surface. The mechanism of deterioration caused by the exposition in the sulfate-bearing soil is discussed. SyXRD is shown to be a reliable method for investigation of cementitious materials with aggregates embedded in natural environments.
KW - X-ray diffraction (B)
KW - High resolution
KW - Degradation (C)
KW - Sulfate attack (C)
KW - Concrete (E)
PY - 2014
DO - https://doi.org/10.1016/j.cemconres.2014.07.015
SN - 0008-8846
SN - 1873-3948
VL - 66
SP - 19
EP - 26
PB - Pergamon Press
CY - New York, NY
AN - OPUS4-31253
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stroh, Julia
A1 - Schlegel, Moritz-Caspar
A1 - Schmidt, Wolfram
A1 - Nguyen, Thi Yen
A1 - Meng, Birgit
A1 - Emmerling, Franziska
T1 - Time-resolved in situ investigation of Portland cement hydration influenced by chemical admixtures
N2 - Numerous admixtures are used in the building practice to customize the properties of the cement paste during application. The influences of admixtures on the course of cement hydration and formation of hydrate phases have to be considered. Polycarboxylate ether (PCE) based polymeric superplasticizers (SPs) are known to retard the setting of the cement paste. The extent of the retardation differs depending on the molecular structure of the SP. Additionally, the presence of a stabilizing agent (SA) in the cement paste has a retarding side effect on the setting. The initial cement hydration processes and the detailed mechanisms of the retardation influenced by PCEs, as well as their interactions with particular SAs, are insufficiently understood. Up to now, only the results of phenomenological studies were taken into account to describe this retardation process. A detailed structure analysis monitoring the change of the phase composition during the hydration was never applied. Both SP and SA affect the adsorption of the sulphate ions on the clinker particles, causing changes in the formation of ettringite during the initial hydration, and are therefore a crucial part of the setting process itself. Here, the initial hydration of cement influenced by the interaction of SP and SA was monitored in situ by synchrotron X-ray diffraction. The high time resolution of the measurements allowed a continuous detection of the hydrates formed. The hydration was followed from the starting point of water addition and for couple of hours afterwards. The hydration of the levitated cement pellets containing starch as SA was initialized by adding aqueous solutions of different commercial SPs. Changes in the ettringite formation were detected in comparison to the reference hydration of pure cement.
KW - Synchrotron
KW - Portland cement Initial hydration
KW - Superplasticizer
KW - Stabilizer
KW - XRD
PY - 2016
DO - https://doi.org/http://dx.doi.org/10.1016/j.conbuildmat.2015.12.097
IS - 106
SP - 18
EP - 26
PB - Elsevier
AN - OPUS4-35467
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stößer, R.
A1 - Feist, M.
A1 - Patzwaldt, K.
A1 - Menzel, Michael
A1 - Emmerling, Franziska
ED - Brooks, H.
T1 - Redox reactions of K3[Fe(CN)6] during mechanochemically stimulated phase transitions of AlOOH
N2 - Thermally induced redox reactions of K3[Fe(CN)6] (1) were investigated for a broad temperature range by thermal methods and structure analytical methods (ESR and Mößbauer spectroscopy, X-ray Powder diffraction and XANES). Based on the influence of the mechanically activated and transforming matrices 2 and 3, redox processes can be tuned to form doped Al2O3 systems which contain either isolated Fe3+ centres or redox active phases and precursors like (Al1-xFex)2O3 (4), (Al3-xFex)O4 (5), Fe3O4, Fe2O3 and Fe0. The phase Fe3C and the chemically reactive C-species were detected during the reaction of 1. The final composition of the doped products of α-Al2O3 is mainly influenced by the chemical nature of the Fe doping component, the applied temperature and time regime, and the composition of the gas phase (N2, N2/O2 or N2/H2). From the solid state chemistry point of view it is interesting that the transforming matrix (2 and 3) possesses both oxidative and protective properties and that the incorporation of the Fe species can be performed systematically.
KW - A. Inorganic compounds
KW - C. Mössbauer spectroscopy
KW - C. Thermogravimetric analysis
KW - D. Electron paramagnetic resonance
KW - ESR-Spektroskopie
KW - Kaliumhexacyanoferrat(III)
KW - Mechanische Aktivierung
KW - Mößbauer-Spektroskopie
KW - Redoxreaktionen
KW - TA-MS-Messungen
PY - 2011
DO - https://doi.org/10.1016/j.jpcs.2011.03.016
SN - 0022-3697
VL - 72
IS - 6
SP - 794
EP - 799
PB - Pergamon Press
CY - New York, NY
AN - OPUS4-23685
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stößer, R.
A1 - Feist, M.
A1 - Willgeroth, Carola
A1 - Emmerling, Franziska
A1 - Menzel, Michael
A1 - Reuther, H.
T1 - The 'quiet Goldschmidt' - a mechanochemical, thermoanalytical, and spectroscopic study of selected steps of the aluminothermic reaction
N2 - The Goldschmidt reaction (2Al+α-Fe2O3) was investigated both under mechanical and thermal activation by employing a combination of analytical methods such as ESR and Mössbauer spectroscopy, magnetic susceptibility, X-ray powder diffraction, and thermal analysis (TA). Both the mechanical treatment and the TA runs under air caused the reaction conditions of 'quiet redox reactions' due to a retarding effect and enabled a reaction study in a 'slow motion mode'. This allowed to establish distinct partial steps of the integral reaction process depending on the intensity of the mechanical impact, the educt composition, the gas phase composition, and, finally, the thermal excitation in the TA runs. Particular attention was payed to the role of the gas phase and to the reaction of aluminum with differently activated oxygen species. The phlegmatizing effect was traced back to the formation of Al2O3 coverages of the Al particles.
KW - Thermite reaction
KW - Iron ESR and Mössbauer spectroscopy
KW - Mechanochemical activation
KW - Magnetic moments
KW - DTA-TG
KW - XRD
PY - 2013
DO - https://doi.org/10.1016/j.jssc.2013.02.032
SN - 0022-4596
SN - 1095-726X
VL - 202
SP - 173
EP - 190
PB - Elsevier
CY - San Diego, Calif.
AN - OPUS4-29528
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Surov, A.
A1 - Vasilev, N.
A1 - Voronin, A.
A1 - Churakov, A.
A1 - Emmerling, Franziska
A1 - Perlovich, G.
T1 - Ciprofloxacin salts with benzoic acid derivatives: structural aspects, solid-state properties and solubility performance
N2 - n this work, three new pharmaceutical hydrated salts of ciprofloxacin with selected derivatives of benzoic acid, namely 4-hydroxybenzoic acid, 4-aminobenzoic acid and gallic acid, were obtained and systematically investigated by several solid-state analytical techniques. In situ Raman spectroscopy was applied to elucidate the alternative pathways of the solid forms' formation under mechanochemical conditions. Crystal structure analysis and a CSD survey allowed us to establish a distinct supramolecular motif formed by infinite columnar stacks of ciprofloxacin dimers arranged in the “head-to-tail” manner. An alternative “head-to-head” packing arrangement was only observed in the crystal of the hydrated ciprofloxacin salt with 4-aminobenzoic acid. In addition, the pH-solubility behavior of the solid forms was thoroughly investigated. Furthermore, a distinct structure–property relationship between the specific features of the supramolecular organization of the hydrated salts and their solubility was observed and discussed.
KW - Mechanochemistry
KW - XRD
PY - 2020
DO - https://doi.org/10.1039/D0CE00514B
VL - 22
IS - 25
SP - 4238
EP - 4249
AN - OPUS4-51818
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Surov, Artem O.
A1 - Vasilev, Nikita A.
A1 - Churakov, Andrei V.
A1 - Stroh, Julia
A1 - Emmerling, Franziska
A1 - Perlovich, German L.
T1 - Solid Forms of Ciprofloxacin Salicylate: Polymorphism, Formation Pathways, and Thermodynamic Stability
N2 - The crystallization of ciprofloxacin - an antibacterial fluoroquinolone compound - with salicylic acid resulted in the isolation of five distinct solid forms of the drug, namely, an anhydrous salt, two polymorphic forms of the salt monohydrate, methanol and acetonitrile solvates, and the salt-cocrystal hydrate. The salicylate salts were investigated by different analytical techniques ranging from powder and single crystal X-ray diffractometry, differential scanning calorimetry, thermogravimetric analysis, variable temperature powder X-ray diffraction, dynamic vapor sorption analysis, dissolution, and solubility investigations. Real-time in situ Raman spectroscopy was used to investigate the mechanochemical formation pathways of the different solid polymorphs of ciprofloxacin salicylate. The mechanism of the phase transformation between the crystalline forms was evaluated under mechanochemical conditions. It was found that the formation pathway and kinetics of the grinding process depend on the form of the starting material and reaction conditions. The analysis of the solid-state thermal evolution of the hydrated salts revealed the two-step mechanism of dehydration process, which proceeds through a formation of the distinct intermediate crystalline products.
KW - Cocrystal
KW - Polymorphism
KW - Ciprofloxacin
KW - XRD
KW - DSC
PY - 2019
DO - https://doi.org/10.1021/acs.cgd.9b00185
SN - 1528-7483
VL - 19
IS - 5
SP - 2979
EP - 2990
PB - American Chemical Society
AN - OPUS4-47903
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Takao, S.
A1 - Takao, K.
A1 - Kraus, Werner
A1 - Emmerling, Franziska
A1 - Scheinost, A.C.
A1 - Bernhard, G.
A1 - Hennig, C.
T1 - First hexanuclear U IV and Th IV formate complexes - Structure and stability range in aqueous solution
KW - Actinides
KW - Polynuclear species
KW - Formic acid
KW - Bridging ligands
PY - 2009
DO - https://doi.org/10.1002/ejic.200900899
SN - 1434-1948
SN - 1099-0682
VL - 2009
IS - 32
SP - 4771
EP - 4775
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-20329
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Thünemann, Andreas
A1 - Kegel, Jenny
A1 - Polte, Jörg
A1 - Emmerling, Franziska
T1 - Superparamagnetic Maghemite Nanorods: Analysis by Coupling Field-Flow Fractionation and Small-Angle X-ray Scattering
N2 - We report on the online coupling of asymmetrical flow field-flow fractionation (A4F) with small-angle X-ray scattering (SAXS) for the detection of nanoparticles. The A4F was used to fractionate superparamagnetic maghemite nanoparticles, which were prepared continuously with a micromixer. The outlet of the A4F was directly coupled to a flow capillary of a SAXSess instrument (Kratky type of camera). SAXS curves were recorded in a 1 s time interval. This was possible by using intense synchrotron radiation. The radii of gyration of the nanoparticles, as determined from Guinier plots, increased from 2 to 6 nm with increasing fractionation time of the A4F. A more detailed analysis of the scattering curves revealed that the particles were cylindrical in shape (nanorods), which we attributed to the micromixing preparation technique. The radii of the nanorods increased only slightly from 1.2 to 1.7 nm with increasing fractionation time, while the lengths increased strongly from 7.0 to 30.0 nm. The volume distribution of the nanorods was determined and described by Schultz-Zimm and log-normal distributions. Nanorod volumes increased from 45 to 263 nm³, corresponding to molar masses of 140 × 10³ to 820 × 10³ g mol-1. We propose A4F-SAXS coupling as a new method for analysis of nanoparticles of complex composition in solution. It allows precise online determination of the particles shape and size distributions. This method can be applied to mixtures of nanoparticles of arbitrary shapes and sizes (1-100 nm). Moreover, the total time needed for fractionation and online SAXS data recording is usually only 20 min.
PY - 2008
DO - https://doi.org/10.1021/ac8004814
SN - 0003-2700
SN - 1520-6882
VL - 80
IS - 15
SP - 5905
EP - 5911
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-17813
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Trowitzsch-Kienast, W.
A1 - Rühl, M.
A1 - Kim, K.Y.
A1 - Emmerling, Franziska
A1 - Erben, U.
A1 - Somasundaram, R.
A1 - Freise, C.
T1 - Absolute configuration of antifibrotic (+)-episesamin isolated from Lindera obtusiloba BLUME
N2 - Fractionation of a 70% ethanolic extract from twigs of Lindera obtusiloba BLUME (Japanese spicebush, Tohaku) yielded fi ve fractions of different polarity. The antifi brotic activity within the chloroform phase was best assessed by an in vitro bioassay using rat hepatic stellate cell (HSC) proliferation and their autocrine transforming growth factor beta (TGF-β) expression as sensitive fibrosis-associated read out. Chromatography of the chloroform extract on Sephadex LH-20 or liquid-liquid extractions yielded a crystalline compound as an active principle, which was identifi ed from NMR and ESI-MS analyses, its melting point, and its optical rotation as (7S,7'S,8S,8'S)-3,4:3',4'-bis(methylenedioxy) -7,9':7',9-diepoxy-lignane [(+)-episesamin]. X-Ray diffraction confirmed the structure and provided, for the fi rst time, directly its absolute confi guration. (+)-Episesamin blocked proliferation and the profi brotic autocrine TGF-β expression HSC without signifi cant cytotoxicity.
KW - TGF-beta
KW - Liver Fibrosis
KW - X-Ray Structure
PY - 2011
SN - 0939-5075
SN - 0341-0382
SN - 0341-0471
VL - 66c
IS - 9/10
SP - 460
EP - 464
PB - Verl. d. Zeitschrift für Naturforschung
CY - Tübingen
AN - OPUS4-24716
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tuchalski, G.
A1 - Emmerling, Franziska
A1 - Gröger, K.
A1 - Hänsicke, A.
A1 - Nagel, T.
A1 - Reck, Günter
T1 - X-ray investigations of nebivolol and its isomers
N2 - The molecular and crystal structures of the hydrochlorides of d-nebivolol, dl-nebivolol, and seven nebivolol isomers have been determined by X-ray structure analysis. The absolute configuration of all the compounds could be determined unambiguously using anomal dispersion effects. Two compounds, dl-nebivolol (NEB-1d,l) and the (S,R,S,R) nebivolol isomer (NEB-6), crystallize as racemic mixtures in the centrosymmetric space group P-1. d-Nebivolol and six nebivolol isomers crystallize in space group P212121. The d- and l-nebivolol molecules in NEB-1d and NEB-1d,l adopt a conformation which is significantly different compared with that of all nebivolol isomers. With the exception of dl-nebivolol (NEB-1d,l) numerous intermolecular hydrogen bonds connect the molecules forming molecular layers.
KW - X-ray crystal structure
KW - Nebivolol
PY - 2006
DO - https://doi.org/10.1016/j.molstruc.2006.03.086
SN - 0022-2860
SN - 1872-8014
SN - 0377-046X
VL - 800
IS - 1-3
SP - 28
EP - 44
PB - Elsevier
CY - Amsterdam
AN - OPUS4-13800
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tumanova, N.
A1 - Tumanov, N.
A1 - Robeyns, K.
A1 - Fischer, Franziska
A1 - Fusaro, L.
A1 - Morelle, F.
A1 - Ban, V.
A1 - Hautier, G.
A1 - Filinchuk, Y.
A1 - Wouters, J.
A1 - Leyssens, T.
A1 - Emmerling, Franziska
T1 - Opening Pandora’s Box: Chirality, Polymorphism, and Stoichiometric Diversity in Flurbiprofen/Proline Cocrystals
N2 - Proline has been widely used for various cocrystallization applications, including pharmaceutical cocrystals. Combining enantiopure and racemic flurbiprofen and proline, we discovered 18 new crystal structures. Liquid-assisted grinding proved highly efficient to explore all the variety of crystal forms. A unique combination of stateof-the-art characterization techniques, comprising variable temperature in situ X-ray diffraction and in situ ball-milling, along with other physicochemical methods and density functional theory calculations, was indispensable for identifying all the phases. Analyzing the results of in situ ball-milling, we established a stepwise mechanism for the formation of several 1:1 cocrystals via an intermediate 2:1 phase. The nature of the solvent in liquidassisted grinding was found to significantly affect the reaction rate and, in some cases, the reaction pathway.
KW - Mechanochemistry
KW - Polymorphs
KW - In situ
PY - 2018
UR - https://pubs.acs.org/doi/abs/10.1021/acs.cgd.7b01436
DO - https://doi.org/10.1021/acs.cgd.7b01436
VL - 18
IS - 2
SP - 954
EP - 961
PB - American Chemical Society
AN - OPUS4-44365
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Unterlass, M.M.
A1 - Emmerling, Franziska
A1 - Antonietti, M.
A1 - Weber, J.
T1 - From dense monomer salt crystals to CO2 selective microporous polyimides via solid-state polymerization
N2 - Fully aromatic polyimides are synthesized via solid-state polymerization of the corresponding monomer salts. The crystal structure of salts shows strong hydrogen bonding of the reactive groups and thereby paves the way for solid-state transformations. The polycondensation yields copies of the initial salt crystallite habits, accompanied by the development of a porosity especially suited for CO2.
PY - 2014
DO - https://doi.org/10.1039/c3cc47674j
SN - 0022-4936
SN - 0009-241x
SN - 1359-7345
SN - 1364-548x
VL - 50
IS - 4
SP - 430
EP - 432
PB - Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-29813
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Villajos Collado, José Antonio
A1 - Bienert, M.
A1 - Gugin, Nikita
A1 - Emmerling, Franziska
A1 - Maiwald, Michael
T1 - A database to select affordable MOFs for volumetric hydrogen cryoadsorption considering the cost of their linkers
N2 - Physical adsorption at cryogenic temperature (cryoadsorption) is a reversible mechanism that can reduce the pressure of conventional compressed gas storage systems. Metal–organic framework (MOF) materials are remarkable candidates due to the combination of high specific surface area and density which, in some cases, provide a high volumetric storage capacity. However, such extensive use of MOFs for this application requires the selection of affordable structures, easy to produce and made from feasible metallic and organic components. Herein, we introduce a MOF database detailing the crystallographic and porous properties of 3600 existing MOFs made from industrially relevant metals and their organic composition. The comparison of the available minimum costs of linkers allowed the creation of a database to select affordable structures with high potential for volumetric hydrogen storage by cryoadsorption, considering their composition based on individual or mixed building blocks. A user inter� face, available online, facilitates the selection of MOFs based on the properties or names of structures and linkers.
KW - MOF´s
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583619
DO - https://doi.org/10.1039/d3ma00315a
VL - 4
IS - 18
SP - 4226
EP - 4237
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58361
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Walter, Astrid
A1 - Pfeifer, Dietmar
A1 - Kraus, Werner
A1 - Emmerling, Franziska
A1 - Schneider, Rudolf
A1 - Panne, Ulrich
A1 - Weller, Michael G.
T1 - Triacetone Triperoxide (TATP): Hapten design and development of antibodies
N2 - Triacetone triperoxide (TATP), an improvised explosive, is a potential security threat because of its cost-efficient synthesis and the difficulty in detecting it. A highly selective antibody could provide the necessary specificity to the detection process. To obtain antibodies, a hapten made from acetone, hydrogen peroxide, and 7-oxooctanoic acid has been designed, synthesized, and confirmed by NMR that displays the utmost similarity to the analyte. The single-crystal X-ray structures of the solvated species TATP·methanol (1:1) and the TATP derivate were determined. In both compounds, the molecules exhibit D3 symmetry and adopt a twisted boat-chair conformation. The hapten was coupled to bovine serum albumin, and mice were immunized. An immune response against TATP was elicited, and selective antibodies were detected in the mouse serum, which should be very useful for the development of a TATP biosensor system. An ELISA with a limit of detection for TATP of 65 µg L-1 is shown.
KW - TATP
KW - Triacetone triperoxide
KW - Explosive
KW - Antibody
KW - Hapten immunoassay
KW - Structure
PY - 2010
DO - https://doi.org/10.1021/la1018339
SN - 0743-7463
SN - 1520-5827
VL - 26
IS - 19
SP - 15418
EP - 15423
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-22469
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Walther, M.
A1 - Matterna, M.
A1 - Juran, S.
A1 - Fähnemann, S.
A1 - Stephan, H.
A1 - Kraus, Werner
A1 - Emmerling, Franziska
T1 - Imidazole-containing bispidine ligands: synthesis, structure and Cu(II) complexation
N2 - The preparation and characterization of tris-pyridyl bispidine (3,7-diazabicyclo[3.3.1]nonane) derivatives with benzimidazole and imidazole donor groups at the N-3 position of the bispidine Skeleton and their copper(II) complexes are reported. The impact of the hetaryl substituents on the configurational isomerism of piperidones and their corresponding bispidones has been studied by NMR spectroscopy, revealing the exclusive appearance in the enol form for the piperidones in solution and the trans-configuration regarding the two pyridyl substituents, as well as the sole formation of the unsymmetric exo-endo isomers for the corresponding bispidones. Thus, the bispidones are preorganized ligands for building pentacoordinated complexes, confirmed by the preparation and characterization of the corresponding Cu(II) complexes. Of the di-pyridyl piperidones with benzimidazole and imidazole substituents, and of the Cu(II) complex of the benzimidazole-containing bispidone, Crystals have become available for the analysis by X-ray diffraction, showing that the piperidones form the enol tautomers also in the solid state.
KW - Piperidone
KW - Bispidine
KW - Copper(II)
KW - Configuration isomerism
PY - 2011
SN - 0932-0776
SN - 0340-5087
SN - 0044-3174
VL - 66b
SP - 721
EP - 728
PB - Verl. d. Zeitschrift für Naturforschung
CY - Tübingen
AN - OPUS4-24091
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wegner, Karl David
A1 - Häusler, I.
A1 - Knigge, Xenia
A1 - Hodoroaba, Vasile-Dan
A1 - Emmerling, Franziska
A1 - Reiss, P.
A1 - Resch-Genger, Ute
T1 - One-Pot Heat-Up Synthesis of ZnSe Magic-Sized Clusters Using Thiol Ligands
N2 - The synthesis of two new families of ZnSe magic-sized clusters (MSCs) is achieved using the thiol ligand 1-dodecanethiol in a simple one-pot heat-up approach. The sizes of the MSCs are controlled with the thiol ligand concentration and reaction temperature.
KW - ZnSe
KW - Magic-sized cluster
KW - Dodecanethiol
KW - Semiconductor nanocrystals
KW - One-pot synthesis
PY - 2022
DO - https://doi.org/10.1021/acs.inorgchem.2c00041
VL - 61
IS - 19
SP - 7207
EP - 7211
PB - ACS Publications
CY - Washington, DC (USA)
AN - OPUS4-54880
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -