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 - Parthasarathy, Thiyagaraj
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Ghosh, Soumyajit
T1 - Design of mechanically flexible photoresponsive cyanostilbene molecular crystals
N2 - Photoresponsive molecular crystals have sparked interest owing to their potential application prospects. In this study, we achieved dual mechanical responses of a cyanostilbene-based crystal BN. The crystal exhibited both stress-induced mechanical flexibility and light-induced photomechanical bending. Two distinct mechanical responses are related to different underlying phenomena and were not interlinked. While elasticity is attributed to criss-cross packing arrangement in the isotropic structure, photomechanical bending is attributed to the formation of heterogeneous phase distribution due to monomer to dimer cycloaddition product formation. The crystal did not demonstrate photoswitching activity. However, it exhibited thermal reversibility, highlighting reversible dimer to monomer conversion.
KW - Flexible
KW - Molecular crystals
PY - 2024
DO - https://doi.org/10.1039/D4CE00571F
VL - 26
SP - 4634
EP - 4642
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60888
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Parthasarathy, Thiyagaraj
A1 - Mishra, Manish Kumar
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Ghosh, Soumyajit
T1 - Simultaneously Mechanically Flexible, Photobending, and Acidochromic Cyanostilbene Molecular Crystals
N2 - Molecular crystals that respond to multiple stimuli are gaining significant attention for their potential in smart materials like actuators and sensors. However, imparting multiple stimuli-responsive properties to a single crystal remains a major challenge. Herein, we report two cyanostilbene derivative-based crystals 1 and 2, with various responses to stimuli such as mechanical stress, light, acid vapors, etc. Both crystals 1 and 2 demonstrated mechanical flexibility and reversible acidochromism. Additionally, crystal 1 also exhibited light-induced photobending, which is ascribed to Z to E photoisomerization. Detailed structure–property correlation was established to unravel distinct mechanical responses. The development of these multitasking crystals may find applications in multitasking actuators, anticounterfeiting materials, and more.
KW - Absorption
KW - Crystals
KW - Mechanical flexiblity
KW - Photoisomerization
PY - 2025
DO - https://doi.org/10.1021/acs.cgd.4c01341
VL - 25
IS - 2
SP - 309
EP - 318
PB - American Chemical Society (ACS)
AN - OPUS4-62568
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paul, Sagar
A1 - Dolai, Malay
A1 - Nanda Goswami, Juli
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Drew, Michael G. B.
A1 - Chattopadhyay, Shouvik
A1 - Sarkar, Rabi Sankar
A1 - Sunil, Appu
A1 - Novitchi, Ghenadie
A1 - Moreno-Pineda, Eufemio
A1 - Wernsdorfer, Wolfgang
T1 - From strong to weak interaction: Reconciling SQUID and μSQUID-EPR data in anomalous Co(ii) dimers
N2 - Magnetic molecules have been proposed as scaffolds for novel quantum technologies, ranging from quantum sensing and quantum memory to multilevel quantum bits (qudits) and fault-tolerant quantum computation. Integration of magnetic molecules into cutting-edge applications hinges on a deep understanding and tunability of their spin states. To date, the strategic manipulation of the local environment of the ion and careful selection of the magnetic core have enabled the desired tunability and scalability of the spin states. For such goals, however, extracting the anisotropic parameters that dictate the characteristics of the Spin Hamiltonian is challenging, especially for molecules consisting of multiple magnetic cores. We address these challenges by studying two cobalt(II) dinuclear systems, complicated by inherent spin–orbit coupling. We explore the magnetic properties of these systems in two temperature regimes: (i) at sub-Kelvin temperatures employing single crystals at 30 mK using a unique μSQUID-EPR technique that examines the microwave absorption peaks in the magnetisation data and their variation with field angle and frequency; and (ii) in bulk employing convectional SQUID magnetometry above 2 K i.e., χMT(T) and M(H). Unexpectedly, sub-Kelvin temperature investigations reveal a negligible interaction, whereas the SQUID data reveal a much stronger interaction between the Co(II) ions. An understanding of these data is developed based on a strong coupling model and the coupling of two moieties with a spin-effective ground state.
KW - cOBALT(II)-complex
KW - In situ complex formation
KW - Magnetic property
KW - Crystal structure
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641421
DO - https://doi.org/10.1039/D5QI01387A
SN - 2052-1553
SP - 1
EP - 13
PB - Royal Society of Chemistry (RSC)
CY - Cambridge
AN - OPUS4-64142
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pavlidis, Sotirios
A1 - Fischer, Eric W.
A1 - Opis-Basilio, Amanda
A1 - Bera, Ayan
A1 - Guilherme Buzanich, Ana
A1 - Álvarez-Sánchez, María
A1 - Wittek, Severin
A1 - Emmerling, Franziska
A1 - Ray, Kallol
A1 - Roemelt, Michael
A1 - Abbenseth, Josh
T1 - Ambiphilic Reactivity and Switchable Methyl Transfer at a T-Shaped Bi(NNN) Complex Enabled by a Redox-Active Pincer Ligand
N2 - We report the transition-metal-like reactivity of a geometrically constrained, ambiphilic bismuth(III) trisamide. Planarization of the Bi(III) center unlocks Bi−C bond formation when reacted with mild electrophiles (alkyl iodides and triflates) accompanied by two-electron oxidation of the utilized NNN pincer nligand. The preservation of the bismuth oxidation state is confirmed by single-crystal X-ray diffraction and X-ray absorption spectroscopy and corroborated by theoretical calculations. Sequential reduction of the oxidized ligand framework alters the reactivity of a generated Bi−Me unit, enabling controlled access to methyl cation, radical, and anion equivalents. The full [Bi(Me)(NNN)]+/•/− redox series was comprehensively characterized using NMR and EPR spectroscopy as well as spectro-electrochemistry. This work represents the first example of ligand-assisted, redox-neutral C−X bond splitting at bismuth, establishing a new paradigm for synthetic bismuth chemistry.
KW - Pincer ligand
KW - XAS
KW - Redox
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654948
DO - https://doi.org/10.1021/jacs.5c18955
SN - 0002-7863
VL - 148
IS - 2
SP - 2683
EP - 2692
PB - American Chemical Society (ACS)
AN - OPUS4-65494
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pavlidis, Sotirios
A1 - Teutloff, Christian
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Krause, Konstantin B.
A1 - Emmerling, Franziska
A1 - Bittl, Robert
A1 - Abbenseth, Josh
T1 - A Crystalline Bismuth(II) Radical Anion: Synthesis, Characterization, and Reactivity
N2 - AbstractWe report the synthesis of a planarized tris‐amidobismuthane supported by a rigid, bulky NNN pincer ligand, which enforces a T‐shaped geometry at the bismuth center. The Bi(NNN) complex features a low‐lying LUMO with distinct Bi(6p) orbital character as shown by DFT calculations. Cyclic voltammetry reveals a fully reversible one‐electron reduction at E1/2 = –1.85 V versus Fc0/+ in THF. Chemical reduction with KC8 in the presence of 4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane (222‐crypt) enables the isolation of an unprecedented Bi(II) radical anion in high isolated yields. Multi‐frequency EPR, X‐ray absorption spectroscopy and SQUID magnetometry complemented by theoretical calculations confirm localization of the unpaired electron on the bismuth center. Preliminary reactivity studies display radical reactivity as shown by single‐electron transfer chemistry and radical coupling reactions.
KW - Bi(III)
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644143
DO - https://doi.org/10.1002/anie.202515545
SN - 1433-7851
VL - 64
IS - 49
SP - 1
EP - 6
PB - Wiley VHC-Verlag
AN - OPUS4-64414
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 - de Oliveira 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, Akash M
A1 - Patel, Rishi I
A1 - Bhatt, Vidhi
A1 - Mosaffa, Elias
A1 - Bhattacharya, Biswajit
A1 - Manna, Arun K
A1 - Iyer, Bragadish
A1 - Emmerling, Franziska
A1 - Banerjee, Atanu
T1 - Solvent induced ligand transmuted substituted pyrazole housed copper complexes: Synthesis, characterization, DFT and anti-microbial performance
N2 - Pyrazole-based ligand systems 3,5-dimethylpyrazole (L1) and 1-hydroxymethyl-3,5-dimethylpyrazole (L2OH) were synthesized and utilized to form copper complexes in various solvent environments. The ligand L2OH exhibits significant solvent-induced ligand transformation in polar protic solvent. The structural and electronic characteristics of the synthesized complexes were elucidated by X-ray single crystallography, Fourier Transform Infrared (FTIR) and electronic spectroscopy (UV-VIS). Whereas the ligand transformation has been evidenced from FTIR and Nuclear Magnetic Resonance (NMR) spectroscopic techniques. Furthermore, Density Functional Theory (DFT) highlights the pivotal role of solvent effects in modulating ligand transformations and complex formation, contributing to the rational design of metal-based bioactive compounds. Electronic transitions of the metal complexes have been analysed by time-dependent DFT (TD-DFT) calculations. The findings reinforce the significance of transition metal complexes in the development of antimicrobial agents and metallo-pharmaceuticals. The synthesized pyrazole compounds showed 100% inhibition against bacterial strains Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis and the yeast Candida albicans at a concentration ranging from 3.9 to 62.5 µg/ml depending upon the strain tested.
KW - Pyrazole derivatives
KW - Antibacterial and antifungal activity
KW - Solvent induced ligand transformation Copper complexes
KW - DFT study
PY - 2025
DO - https://doi.org/10.1016/j.molstruc.2025.143001
SN - 0022-2860
VL - 1345
SP - 1
EP - 12
PB - Elsevier B.V.
AN - OPUS4-63746
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 - Rodríguez-Sánchez, Noelia
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Prinz, Carsten
A1 - Prieto-Laria, P.
A1 - Ruiz-Salvador, A.R.
A1 - Ballesteros, M.
T1 - Engineering a multivariate cobalt metal–organic framework for high photocatalytic activity: the impact of mixed ligands and metal incorporation in a visible light-driven heterogeneous photo-Fenton reaction for water treatment
N2 - Metal–organic frameworks (MOFs) have attracted increasing attention for the removal of organic pollutants in wastewater via photocatalysis. Here, we design a multivariate modification of ZIF-9 to tune its electronic properties for use in visible light photocatalysis. A controllable synthesis of ZIF-9 and its multivariate forms with the incorporation of copper and the 2-imidazolecarboxaldehyde (ica) ligand was carried out. The materials are tested for the removal of the model dye methylene blue (MB) by a heterogeneous photo-Fenton-like reaction at neutral pH and room temperature. Cu-ZIF-9-ica (UPO-3) shows high photocatalytic activity under both visible and ultraviolet A (UVA) light, achieving 94% MB degradation in 45 min, compared to 65% MB degradation in 120 min using bare ZIF-9. The study revealed a first-order rate constant of 0.0475 min−1 for Cu-ZIF-9-ica compared to 0.0088 min−1 for ZIF-9 under visible light. The improvement of the catalyst was clearly attributed to the co-incorporation of Cu and the ica ligand in the MOF, which reduces the band gap, in agreement with DFT calculations. Reproducibility and recyclability tests proved that Cu-ZIF-9-ica can be used for at least 3 cycles without a significant loss of efficiency, making it a promising material for the study and application of wastewater treatment.
KW - Metal-Organic Framework (MOF)
KW - Heterogeneous photo-Fenton
KW - ZIF-9
KW - Methylene Blue
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630797
DO - https://doi.org/10.1039/d4na00954a
SN - 2516-0230
VL - 7
IS - 8
SP - 2255
EP - 2265
PB - Royal Society of Chemistry
AN - OPUS4-63079
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rodríguez-Sánchez, Noelia
A1 - Domínguez-Santos, J. Enrique
A1 - Bhattacharya, Biswajit
A1 - Prinz, Carsten
A1 - Canosa, Inés
A1 - Flores, Amando
A1 - Jiménez-Rodríguez, Antonia
A1 - Ruiz-Salvador, A. Rabdel
A1 - Emmerling, Franziska
A1 - Ballesteros, Menta
T1 - Mechanochemical synthesis of multivariate UPO-3 (Cu-ZIF-9-ica) MOF for inactivation of antibiotic-resistant bacteria and irrigation-quality water production via heterogeneous photo-Fenton catalysis
N2 - Water scarcity and pollution are critical global challenges, particularly in agriculture, the largest consumer of water. The development of sustainable, effective, and environmentally friendly disinfection methods is essential to address the risks posed by antibiotic-resistant bacteria and to ensure safe reuse of water for irrigation. In this study, we report the synthesis of the metal-organic framework (MOF) Universidad Pablo de Olavide-3 (UPO-3) via a mechanochemical approach, a scalable and sustainable method compared to traditional solvothermal synthesis. The resulting UPO-3/H2O2 system exhibits robust photocatalytic properties under visible light, achieving effective and broad-spectrum antibacterial activity. The disinfection efficiency of the catalyst was evaluated against Escherichia coli as a model of microbial pathogen in two saline matrices, considering the key parameters of the heterogeneous photo-Fenton process, including catalyst dosage, initial H2O2 concentration, and light irradiation. Notably, it inactivated two important virulent and antibiotic-resistant bacterial pathogens (Staphylococcus aureus and Pseudomonas aeruginosa). Furthermore, UPO-3 shows exceptional performance under real-world conditions, such as river water disinfection, achieving >5-log reduction of E. coli, fulfilling a critical criterion for Class A water reuse under Regulation (EU) 2020/741. These results highlight UPO-3 as a versatile and sustainable solution for water reuse, addressing water scarcity and advancing efforts to achieve United Nations Sustainable Development Goal 6.
KW - Water reuse
KW - Antibiotic-resistant bacteria
KW - Water disinfection
KW - Mechanochemical synthesis
KW - Metal organic framework
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639766
DO - https://doi.org/10.1016/j.chemosphere.2025.144610
SN - 0045-6535
VL - 386
SP - 1
EP - 11
PB - Elsevier Ltd.
AN - OPUS4-63976
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rodríguez-Sánchez, Noelia
A1 - Prinz, Carsten
A1 - Bienert, Ralf
A1 - Ballesteros, Menta
A1 - Ruiz Salvador, A. Rabdel
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Mechanochemical ZIF-9 formation: in situ analysis and photocatalytic enhancement evaluation
N2 - Efficient treatment of persistent pollutants in wastewater is crucial for sustainable water management and environmental protection. This study addresses this challenge by investigating the mechanochemical synthesis and photocatalytic performance of ZIF-9, a cobalt-based zeolitic imidazolate framework. Using synchrotron-based powder X-ray diffraction, we provide real-time insights into the formation dynamics of ZIF-9 during mechanosynthesis. Our results show that mechanochemically synthesised ZIF-9 exhibits superior photocatalytic activity compared to its solvothermally prepared counterpart, achieving a 2-fold increase in methylene blue degradation rate. This research not only advances our understanding of the synthesis and properties of ZIF-9, but also demonstrates the potential of mechanochemical approaches in the development of high-performance, sustainably produced materials for water treatment and other environmental applications.
KW - MOFs
KW - ZIF
KW - Time-resolved in situ investigation
KW - Photocatalysis synchrotron X-ray powder diffraction
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641416
DO - https://doi.org/10.1039/D4MR00114A
SN - 2976-8683
VL - 2
IS - 1
SP - 116
EP - 126
PB - Royal Society of Chemistry (RSC)
CY - Cambridge
AN - OPUS4-64141
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Roy, Arkendu
A1 - Kumar, Sourabh
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Prinz, Carsten
A1 - Götz, Emilia
A1 - Retzmann, Anika
A1 - Hickel, Tilmann
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Synergistic Catalytic Sites in High‐Entropy Metal Hydroxide Organic Framework for Oxygen Evolution Reaction
N2 - AbstractThe integration of multiple elements in a high‐entropy state is crucial in the design of high‐performance, durable electrocatalysts. High‐entropy metal hydroxide organic frameworks (HE‐MHOFs) are synthesized under mild solvothermal conditions. This novel crystalline metal–organic framework (MOF) features a random, homogeneous distribution of cations within high‐entropy hydroxide layers. HE‐MHOF exhibits excellent electrocatalytic performance for the oxygen evolution reaction (OER), reaching a current density of 100 mA cm−2 at ≈1.64 VRHE, and demonstrates remarkable durability, maintaining a current density of 10 mA cm−2 for over 100 h. Notably, HE‐MHOF outperforms precious metal‐based electrocatalysts despite containing only ≈60% OER active metals. Ab initio calculations and operando X‐ray absorption spectroscopy (XAS) demonstrate that the high‐entropy catalyst contains active sites that facilitate a multifaceted OER mechanism. This study highlights the benefits of high‐entropy MOFs in developing noble metal‐free electrocatalysts, reducing reliance on precious metals, lowering metal loading (especially for Ni, Co, and Mn), and ultimately reducing costs for sustainable water electrolysis technologies.
KW - Electrocatalysis
KW - Green Hydrogen
PY - 2024
DO - https://doi.org/10.1002/adma.202408114
SP - 1
EP - 14
PB - Wiley
AN - OPUS4-61739
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
EP - 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 -