TY - JOUR
A1 - Emmerling, Franziska
A1 - Hoch, C.
T1 - Laudatio Prof. Dr.-Ing. Caroline Röhr
N2 - It is a laudatio on the ocations of Prof. Dr.-Ing. Caroline Röhrs 60th birthday.
KW - Metal-oxides
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561877
DO - https://doi.org/10.1002/zaac.202200159
SN - 0044-2313
VL - 648
IS - 10
SP - 1
EP - 2
PB - John Wiley & Sons, Ltd
AN - OPUS4-56187
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Abed, Jehad
A1 - Bai, Yanh
A1 - Persaud, Daniel
A1 - Kim, Jiheon
A1 - Witt, Julia
A1 - Hattrick.Simpers, Jason
A1 - Sargent, Edward
T1 - AMPERE: automated modular platform for expedited and reproducible electrochemical testing
N2 - Rapid and reliable electrochemical screening is critical to accelerate the development of catalysts for sustainable energy generation and storage. This paper introduces an automated and modular platform for expedited and reproducible electrochemical testing (AMPERE), designed to enhance the efficiency and reliability of multivariate optimization. The platform integrates a liquid-handling robot with custommade modular array reactors, offering sample preparation and electrochemical testing in the same platform. Additionally, we use offline inductively coupled plasma optical emission spectroscopy (ICPOES) to measure metal concentrations in the electrolyte after the reaction, which serves as a proxy for assessing the electrochemical stability. We use the platform to conduct 168 experiments continuously in less than 40 hours to examine the influence of catalyst ink formulation on the performance of Ir, Ru, IrO2, and RuO2 for the oxygen evolution reaction (OER) in acid. We specifically investigate the role of solvent type and concentration, catalyst concentration, and binder content on the performance. We find that Ru/RuO2 catalysts show improvements in activity that are not directly linked to improvements in the electrochemical surface area or inversely correlated to Ru dissolution. This suggests a complex interplay between the catalytic performance of the drop-casted catalyst film and ink formulation. AMPERE simplifies catalyst preparation and testing at large scale, making it faster, more reliable, and accessible for
widespread use.
KW - Electrochemical screening
KW - Automated platform
KW - Catalysis
KW - Energy generation and storage
KW - Oxygen evolution reaction (OER)
KW - MAPz@BAM
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614724
DO - https://doi.org/10.1039/d4dd00203b
SP - 1
EP - 10
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-61472
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Li, Guiping
A1 - Liu, Ye
A1 - Schultz, Thorsten
A1 - Exner, Moritz
A1 - Muydinov, Ruslan
A1 - Wang, Hui
A1 - Scheurell, Kerstin
A1 - Huang, Jieyang
A1 - Szymoniak, Paulina
A1 - Pinna, Nicola
A1 - Koch, Norbert
A1 - Adelhelm, Philipp
A1 - Bojdys, Michael J.
T1 - One‐Pot Synthesis of High‐Capacity Sulfur Cathodes via In‐Situ Polymerization of a Porous Imine‐Based Polymer
N2 - AbstractLithium‐ion batteries, essential for electronics and electric vehicles, predominantly use cathodes made from critical materials like cobalt. Sulfur‐based cathodes, offering a high theoretical capacity of 1675 mAh g−1 and environmental advantages due to sulfur's abundance and lower toxicity, present a more sustainable alternative. However, state‐of‐the‐art sulfur‐based electrodes do not reach the theoretical capacities, mainly because conventional electrode production relies on mixing of components into weakly coordinated slurries. Consequently, sulfur‘s mobility leads to battery degradation—an effect known as the “sulfur‐shuttle”. This study introduces a solution by developing a microporous, covalently‐bonded, imine‐based polymer network grown in situ around sulfur particles on the current collector. The polymer network (i) enables selective transport of electrolyte and Li‐ions through pores of defined size, and (ii) acts as a robust host to retain the active component of the electrode (sulfur species). The resulting cathode has superior rate performance from 0.1 C (1360 mAh g−1) to 3 C (807 mAh g−1). Demonstrating a high‐performance, sustainable sulfur cathode produced via a simple one‐pot process, our research underlines the potential of microporous polymers in addressing sulfur diffusion issues, paving the way for sulfur electrodes as viable alternatives to traditional metal‐based cathodes.
KW - In-situ polymerization
KW - Sulfur cathodes
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604215
DO - https://doi.org/10.1002/anie.202400382
SN - 1433-7851
SP - 1
EP - 11
PB - Wiley VHC-Verlag
AN - OPUS4-60421
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 - Li, Yue
A1 - Colnaghi, Timoteo
A1 - Gong, Yilun
A1 - Zhang, Huaide
A1 - Yu, Yuan
A1 - Wei, Ye
A1 - Gan, Bin
A1 - Song, Min
A1 - Marek, Andreas
A1 - Rampp, Markus
A1 - Zhang, Siyuan
A1 - Pei, Zongrui
A1 - Wuttig, Matthias
A1 - Ghosh, Sheuly
A1 - Körmann, Fritz
A1 - Neugebauer, Jörg
A1 - Wang, Zhangwei
A1 - Gault, Baptiste
T1 - Machine learning‐enabled tomographic imaging of chemical short‐range atomic ordering
N2 - In solids, chemical short‐range order (CSRO) refers to the self‐organization of atoms of certain species occupying specific crystal sites. CSRO is increasingly being envisaged as a lever to tailor the mechanical and functional properties of materials. Yet quantitative relationships between properties and the morphology, number density, and atomic configurations of CSRO domains remain elusive. Herein, it is showcased how machine learning‐enhanced atom probe tomography (APT) can mine the near‐atomically resolved APT data and jointly exploit the technique's high elemental sensitivity to provide a 3D quantitative analysis of CSRO in a CoCrNi medium‐entropy alloy. Multiple CSRO configurations are revealed, with their formation supported by state‐of‐the‐art Monte‐Carlo simulations. Quantitative analysis of these CSROs allows establishing relationships between processing parameters and physical properties. The unambiguous characterization of CSRO will help refine strategies for designing advanced materials by manipulating atomic‐scale architectures.
KW - Chemical short-range order (CSRO)
KW - Atom probe tomography (APT)
KW - Machine learning
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623777
DO - https://doi.org/10.1002/adma.202407564
SN - 1521-4095
VL - 36
IS - 44
SP - 1
EP - 9
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-62377
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schneider, Mike
A1 - Couzinié, Jean-Philippe
A1 - Shalabi, Amin
A1 - Ibrahimkhel, Farhad
A1 - Ferrari, Alberto
A1 - Körmann, Fritz
A1 - Laplanche, Guillaume
T1 - Effect of stacking fault energy on the thickness and density of annealing twins in recrystallized FCC medium and high-entropy alloys
N2 - This work aims to predict the microstructure of recrystallized medium and high-entropy alloys (MEAs and HEAs) with a face-centered cubic structure, in particular the density of annealing twins and their thickness. Eight MEAs and five HEAs from the Cr-Mn-Fe-Co-Ni system are considered, which have been cast, homogenized, cold-worked and recrystallized to obtain different grain sizes. This work thus provides a database that could be used for data mining to take twin boundary engineering for alloy development to the next level. Since the stacking fault energy is known to strongly affect recrystallized microstructures, the latter was determined at 293 K using the weak beam dark-field technique and compared with ab initio simulations, which additionally allowed to calculate its temperature dependence. Finally, we show that all these data can be rationalized based on theories and empirical relationships that were proposed for pure metals and binary Cu-based alloys.
KW - CoCrFeMnNi HEAs and MEAs
KW - Recrystallization
KW - Transmission electron microscopy (TEM)
KW - Electron backscatter diffraction
KW - Grain boundary engineering
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629346
DO - https://doi.org/10.1016/j.scriptamat.2023.115844
SN - 1359-6462
VL - 240
SP - 1
EP - 6
PB - Elsevier
CY - Amsterdam
AN - OPUS4-62934
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reigl, Selina
A1 - Van Driessche, Alexander
A1 - Stawski, Tomasz
A1 - Koltzenburg, Sebastian
A1 - Kunz, Werner
A1 - Kellermeier, Matthias
T1 - Sustainable Pathways for the Synthesis of Calcium Sulfate Hemihydrate
N2 - Calcium sulfate, and especially its hemihydrate form (bassanite), is crucial in the construction industry, primarily used as a hydraulic binder in cements, mortars, and wallboards. Because of the rapid transformation of bassanite into thermodynamically stable gypsum (calcium sulfate dihydrate) upon contact with water, natural deposits are scarce, rendering it one of the most extensively produced inorganic materials worldwide. Currently, bassanite is derived from mined or waste gypsum through a thermal dehydration process, which is energy-intensive and costly. As sustainability has become a key target for industrial processes and products, a series of studies aiming to increase the energy efficiency and reduce the carbon footprint of bassanite production was published recently. Two primary approaches are pursued: conversion of gypsum and direct precipitation of bassanite from solution. In both cases, organic solvents, (specific) additives and/or elevated temperatures have been used to control the activity/availability of water in the reaction medium and thus direct phase selection towards bassanite. This review offers a comprehensive overview of alternative bassanite production methods, critically examining their benefits, potential downsides, and overall impact on
the sustainability of industrial-scale use.
KW - Calcium sulfate
KW - Gypsum
KW - Bassanite
KW - Recycling
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630657
DO - https://doi.org/10.1002/anie.202415161
SN - 1521-3773
SP - 1
EP - 20
PB - Wiley VHC-Verlag
AN - OPUS4-63065
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Omar, Hassan
A1 - Ahmadi, Shayan
A1 - Szymoniak, Paulina
A1 - Schönhals, Andreas
T1 - Molecular Mobility of Thin Films of Poly (bisphenol-A carbonate) Capped and with one Free Surface: From Bulk-like Samples down to the Adsorbed Layer
N2 - The molecular mobility of thin films of poly(bisphenol A carbonate) (PBAC) was systematically investigated using broadband dielectric spectroscopy, employing two distinct electrode configurations. First, films were prepared in a capped geometry between aluminum electrodes employing a crossed electrode capacitor (CEC) configuration, down to film thicknesses of 40 nm. The Vogel temperature, derived from the temperature dependence of relaxation rate of the α-relaxation, increases with decreasing film thickness characterized by an onset thickness. The onset thickness depends on the annealing conditions, with less intense annealing yielding a lower onset thickness. Additionally, a broadening of the β-relaxation peak was observed with decreasing thickness, attributed to the interaction of phenyl groups with thermally evaporated aluminum, resulting in a shift of certain relaxation modes to higher temperatures relative to the bulk material. A novel phenomenon, termed the slow Arrhenius process (SAP), was also identified in proximity to the α-relaxation temperature.
For films with thicknesses below 40 nm, nanostructured electrodes (NSE) were utilized, incorporating nanostructured silica spacers to establish a free surface with air. This free surface causes an enhancement in the molecular mobility for the 40 nm sample, preserving the β-relaxation as a distinct peak. The α-relaxation was detectable in the dielectric loss down to 18 nm, shifting to higher temperatures as film thickness is decreased. Notably, the onset thickness for the increase in Vogel temperature was lower in the NSE configuration compared to the CEC setup, attributed to the presence of the polymer-air interface.
KW - Thin polymer films
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623422
DO - https://doi.org/10.1039/d4sm01238k
SN - 1744-6848
VL - 21
IS - 2
SP - 241
EP - 254
PB - RSC
AN - OPUS4-62342
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Omar, Hassan
A1 - Hiid, Gundula
A1 - Szymoniak, Paulina
A1 - Hertwig, Andreas
A1 - Schönhals, Andreas
T1 - Growth kinetics of the adsorbed layer of poly(bisphenol A carbonate) and its effect on the glass transition behavior in thin films
N2 - The glass transition behavior of thin films of poly(bisphenol A carbonate) (PBAC) was studied employing ellipsometry. The glass transition temperature increases with the reduction of the film thickness. This result is attributed to the formation of an adsorbed layer with a reduced mobility compared to bulk PBAC. Therefore, for the first time, the growth kinetics of the adsorbed layer of PBAC was investigated, prepared by leaching samples from a 200 nm thin film which were annealed for several times at three different temperatures. The thickness of each prepared adsorbed layer was measured by multiple scans using atomic force microscopy (AFM). Additionally, an unannealed sample was measured. Comparison of the measurements of the unannealed and the annealed samples provides proof of a pre-growth regime for all annealing temperatures which was not observed for other polymers. For the lowest annealing temperature after the pre-growth stage only a growth regime with a linear time dependence is observed. For higher annealing temperatures the growth kinetics changes from a linear to a logarithmic growth regime at a critical time. At the longest annealing times the films showed signs of dewetting where segments of the adsorbed film were removed from the substrate (dewetting by desorption). The dependence of the surface roughness of the PBAC surface on annealing time also confirmed that the films annealed at highest temperatures for the longest times desorbed from the substrate.
KW - Ultra thin polymer films
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574531
DO - https://doi.org/10.1039/D3RA02020G
SN - 2046-2069
VL - 13
IS - 21
SP - 14473
EP - 14483
PB - RSC Publishing
CY - London
AN - OPUS4-57453
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mezera, Marek
A1 - Alamri, S.
A1 - Hendriks, W. A. P. M.
A1 - Hertwig, Andreas
A1 - Elert, Anna Maria
A1 - Bonse, Jörn
A1 - Kunze, T.
A1 - Lasagni, A. F.
A1 - Römer, G. R. B. E.
T1 - Hierarchical micro-/nano-structures on polycarbonate via UV pulsed laser processing
N2 - Hierarchical micro/-nanostructures were produced on polycarbonate polymer surfaces by employing a two-step UV-laser processing strategy based on the combination of Direct Laser Interference Patterning (DLIP) of gratings and pillars on the microscale (3 ns, 266 nm, 2 kHz) and subsequently superimposing Laser-induced Periodic Surface Structures (LIPSS; 7–10 ps, 350 nm, 100 kHz) which adds nanoscale surface features. Particular emphasis was laid on the influence of the direction of the laser beam polarization on the morphology of resulting hierarchical surfaces. Scanning electron and atomic force microscopy methods were used for the characterization of the hybrid surface structures. Finite-difference time-domain (FDTD) calculations of the laser intensity distribution on the DLIP structures allowed to address the specific polarization dependence of the LIPSS formation observed in the second processing step. Complementary chemical analyzes by micro-Raman spectroscopy and attenuated total reflection Fourier-transform infrared spectroscopy provided in-depth information on the chemical and structural material modifications and material degradation imposed by the laser processing. It was found that when the linear laser polarization was set perpendicular to the DLIP ridges, LIPSS could be formed on top of various DLIP structures. FDTD calculations showed enhanced optical intensity at the topographic maxima, which can explain the dependency of the morphology of LIPSS on the polarization with respect to the orientation of the DLIP structures. It was also found that the degradation of the polymer was enhanced for increasing accumulated fluence levels.
KW - Direct laser interference patterning
KW - Laser-induced periodic surface structures (LIPSS)
KW - Polycarbonate
KW - Hierarchical structures
KW - Surface functionalization
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509101
DO - https://doi.org/10.3390/nano10061184
SN - 2079-4991
VL - 10(6)
IS - Special issue "Laser-generated periodic nanostructures"
SP - 1184-1
EP - 1184-19
PB - MDPI
CY - Basel
AN - OPUS4-50910
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -