Developing efficient, sustainable thermoelectric (TE) devices to harness waste heat is challenging due to the reliance on rare elements in conventional materials. Recently, conducting polymers, particularly Poly(3,4-methylenedioxy thiophene): poly(styrene sulfonate) (PEDOT: PSS) blends, have shown promising TE performance improvements [1]. However, PEDOT has limitations, such as sensitivity to...
In aqueous solution, amphiphilic block copolymers consisting of a short permanently hydrophobic poly(methyl methacrylate) (PMMA) and a long thermoresponsive poly(N-isopropyl acrylamide) (PNIPAM) block self-assemble into spherical core-shell micelles. At atmospheric pressure, the micellar shell of PMMA-b-PNIPAM strongly dehydrates and shrinks above the cloud point Tcp of PNIPAM. However,...
As space technologies and space missions develop rapidly, the demand for solar cells dedicated to space applications is increasing. Space solar cells face more critical challenges than before. Higher gravimetric Power Density and better radiation resistance are the primary keys. This project aims to investigate the degradation of organic solar cells in the space environment. Based on previous...
Our group operates and/or develops in-situ 3He polarizers/analyzers for the following instruments: MARIA, KWS1, KWS2, TOPAS, POLI (2x), DREAM (ESS), and TREX (ESS). We are also active in developing polarized neutron beam components and testing. We will present a summary of the status and performance of the various devices.
Perovskite Quantum Dot Solar Cells (PQDSC) are very promising in contributing to the renewable energy mix of the future. Perovskite Quantum Dot Layers are used as active layer within solar cells due to the quantum confinement which occurs at crystales size below the Bohr radius.[1] Therefore they provide high power conversion efficiencies, high photoluminescence quantum yield (PLQY), a narrow...
Strongly correlated electron systems (SCES) summarizes phenomena, which cannot be reconciled with the theory of the free electron gas. Instead, significant interactions between electrons are integral to understand these phenomena, mostly at very low temperatures when the impact of thermal fluctuations is low. On the atomic scale, properties like, e.g. spin orbit coupling, reduced magnetic...
Organic-inorganic halide perovskites have gained a huge interest in the scientific community owing to their favorable optoelectronic properties combined with their ease of production and abundance of raw materials. [1] In many cases, polycrystalline thin films are used for which thin film crystallinity and morphology are key factors affecting the perovskite’s properties. Various methods have...
Magnetic dipole traps have demonstrated good confinement properties for both non-neutral and quasi-neutral plasmas, making this a highly suitable type of trap for the creation and study of low-temperature, long-lived electron-positron pair plasmas. To generate such a plasma, the APEX (A Positron-Electron eXperiment) Collaboration is planning to inject positrons (supplied by the reactor-based...
Ordered magnetic hybrid thin films composed of a diblock copolymer (DBC) and magnetic nanoparticles (MNPs) are interesting due to the mixing of properties from the organic and inorganic precursors. The unique attributes of these hybrid films make them attractive for use in applications ranging from magnetic sensors to magnetic data storage devices. In this study, thin DBC films of...
The last pandemic highlighted the importance of understanding the interaction between external sources and eukaryotic membranes. Membrane models have been widely studied, but our knowledge of the interaction between them and external sources is far from fully understood. This gap limits the ability to achieve the next level of selectivity, efficiency, and targeting. Target of respiratory...
Plasmonic nanostructures have attracted extensive research interest due to their enhanced light-matter interactions. Plasmonic induced surface plasmon resonance properties enable strong, size- and shape-dependent light absorption and scattering, as well as near-field amplification. Hybrid nanostructures containing self-assembled gold nanoparticles (Au NPs) embedded in a solid matrix of PbS...
Magnetic systems are a fertile ground for the design of novel quantum and topologically non-trivial states characterized by exotic excitations. Examples include spin chain and square-lattice low-dimensional antiferromagnets, quantum spin liquid candidates, spin-ice compounds, and unusual spin textures. Key features of the ground state and finite-temperature behavior of such magnetic systems...
Metal insulation technology is one of the solutions employed to enhance the quench stability of high-temperature superconductor (HTS) coils. This approach offers several advantages for quench stability. Metal substrate facilitates the detection of quenches by allowing electrical voltage signals to be easily measured across the substrate. This feature is crucial for promptly identifying...
Cellulose, a well-known natural biopolymer, possesses numerous advantages such as cost-effectiveness, renewability, ease of processing, and biodegradability [1]. Due to these inherent merits, cellulose has emerged as a promising bio-based substrate capable of synergistically combining with conductive materials (e.g., metals or carbon-based materials) for diverse applications including sensors,...
Metal oxide interfaces, especially nanostructured titania, play a key role in various energy applications. Achieving controlled morphology at different scales is critical for optimal performance. Nanostructured titania with a high surface-to-volume ratio improves device efficiency. Industrial methods such as spray coating are effective, but often involve unsustainable organic solvents. To...
STRESS-SPEC is the dedicated diffractometer for materials science applications at MLZ. It offers high thermal neutron flux and is mainly used for fast residual strain and texture (bulk, local or gradient) measurements [1, 2]. Recent upgrades include a new detector system developed in-house, a new fully automatic slit system for gauge volume definition of the monochromatic beam, and a quenching...
Biotemplating is an effective method of nanostructuring hybrid
inorganic-organic materials. This approach allows the tuning of material properties like porosity or domain sizes. Therefore, parameters like
the electronic conductivity can be adjusted for different applications.
In this work, differently structured Titania thin films are investigated
for application in thermoelectric...
In this presentation, we will give an overview of the current status of the powder diffractometer SPODI, its performance in user service together with future perspectives. In particular, an overview on the research areas and outcome in user service will be provided.
Poly(N-isopropylacrylamide) based microgels are interesting colloidal systems to probe cooperative phenomena such as structural ordering, crystal nucleation, glass formation, etc. They can be packed to effective volume fractions(eff) beyond the hard-sphere close-packing (cp) and their average interparticle distance, as can be smaller than the particle diameter, d[1]. Here, we report the...
The RESEDA instrument, situated at the FRM II facility, operates as a resonant spin-echo spectrometer utilizing the MIEZE (Modulated Intensity with Zero Effort) technique in a longitudinal geometry. While RESEDA offers access to a broad range of energy scales, its optimal resolution for momentum-transfer vectors is primarily concentrated at small scattering angles. Recent advancements have...
It is crucial to suppress the non-radiation recombination in the hole-blocking layer (HBL) and at the interface between the HBL and active layer for performance improvement. Herein, TiOx layers are deposited onto a SnO2 layer via sputter deposition at room temperature, forming a bilayer HBL. The structure evolution of TiOx during sputter deposition is investigated via in situ grazing-incidence...
The third generation β-solidifying TNM alloys with (α2+γ) lamellar microstructures have been considered excellent candidates for modern turbine blades due to their low density, high specific strength and stiffness, excellent creep resistance, and good corrosion resistance. It has been proved that orienting the γ lamellae to the direction of the load can significantly increase the mechanical...
Properties of Gd3+ rare earth ion incorporated MgFe2-xGdxO4 (0 =< x =< 0.16) ceramics prepared from powders using combustion technique with DL- alanine fuel are investigated. Re-arrangement of cations in the unit cell due to Gd3+ substitution for Fe3+ in MgFe2O4, and the consequent effects on the electrical and magnetic properties are discussed. Improvements in electrical resistivity with...
The small-angle neutron scattering (SANS) diffractometer KWS-2, operated by the Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum in Garching, is equipped with an in-line size exclusion chromatography (SEC) followed by the multi-angle light scattering (MALS) machine. The established SEC-SANS-MALS setup facilitates the in-situ fractionation of the sample solution, the...
We propose to implement a new modulation technique at NREX adding time resolution to polarized neutron reflectometry (PNR). The new technique is based on intensity modulation by a radio-frequency (RF) spin flipper, and shares some basic concepts with the MIEZE spin-echo technique. The aim is to resolve the kinetics of the nuclear and magnetic scattering length densities in periodic processes...
We propose to significantly increase the efficiency of TRSIP for high-resolution spectroscopy and Larmor diffraction. Through optimized beam geometry and development of a spin-echo multi-detector, gain factors of 5-50 in counting time are possible. Shorter spin-echo units in combination with new radio-frequency (RF) spin-flippers will provide a larger flux on the sample. The proposed spin-echo...
Robots and cobots (collaborative robots) were designed to change manufacturing and production processes at factories. Typical application of an industrial robot would be to replace a human on repetitive tasks, which involve endurance, speed, and precision. Industrial robots usually operate in environments isolated from human contact. Instead, cobots are designed to provide human robot...
QtiSAS [1, 2] is an open-source cross-platform software designed for the graphical visualization, reduction, analysis, and fit of data. At Jülich Centre for Neutron Science (JCNS) it is designed particularly to work on data produced by small-angle neutron scattering (SANS) instruments, however it could also be an alternative to proprietary scientific software like Origin or Igor...
The author will present the actual status of the work at the MEPHISTO beamline. The installation of the neutron guide shielding in the reactor building is progressing and the cooling plant await its compressor housing construction.
Milk and dairy products are common food systems. One of their important constituents is casein micelles (CM) (~10-100 nm) that form extended aggregates, and further develop into a network by the process of gelation. A key structural parameter is the fractal dimension (Df) of this network[1-3]. Scattering and rheology have been explored in the past to access the relevant length scales and Df of...
The high-intensity reflectometer MARIA of JCNS is installed at the neutron guide hall of the FRM II reactor in Garching and it is a state of the art reflectometer at a constant flux reactor. It gives the opportunity to investigate specular reflectivity curves in a broad dynamic range including off-specular scattering and GISANS measurements. The availability of a polarised neutron beam and the...
Hydrogel films made from responsive polymers are able to switch between a swollen (extended polymer chains) and a contracted film state (coiled polymer chains) in response to slight changes in their surroundings. In recent studies, we demonstrated the versatility of a multi-responsive diblock copolymer, containing a zwitterionic poly(sulfobetaine) and a nonionic poly(N-isopropyl acrylamide)...
Hydrogen is one of innovative fuels which storage is a challenge so far. One of options is hydrogen storage in complex-hydride systems, where it is chemically bonded unless a sufficient heating is applied. Main virtues of a hydrogen storage system are: storage capacity, safety of use, reversibility, fast reaction rate and a moderate operation temperature. Amide-hydride mixtures, where...
Single chain nanoparticles are soft nano-objects made from individual polymer chains crosslinked intramolecularly. Due to the internal random crosslinking between functional groups of the same chain, a sparse conformation is usually achieved which displays many common structural features with intrinsically disordered proteins (IDPs). Lately, there has been great interest in expanding SCNPs to...
The PERC facility is currently under construction at the FRM II in Garching, Germany. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to improve the measurements of the properties of weak interaction by one order of magnitude and to search for new physics via new effective couplings.
PERC's central component is a 12...
Ordered porous gold/titanium dioxide (Au/TiO2) hybrid nanostructured films are specifically interesting in large-scale applications using localized surface plasmon resonances (LSPRs) and surface-enhanced Raman scattering (SERS). In this work, we investigate the optical response of sputter-deposited Au/TiO2 nanohybrid thin films with a focus on the plasmonic response and application as...
Located at the SR10 at the FRM II, NECTAR is a versatile instrument and designed for the non-destructive inspection of various objects by means of fission neutron radiography and tomography. Compared to the Z-dependency of X-ray and gamma imaging, fission neutrons have the strong advantage of often providing similar contrast for heavy and light materials. Only few facilities around the world...
Modulation of intensity with zero effort (MIEZE) is a neutron spectroscopy technique with high energy resolution, closely related to the established neutron spin echo (NSE) method. The essential feature of MIEZE is an intensity modulated neutron beam with a focal point (echo point) several meters downstream the sample.
Successful employment of the MIEZE technique requires careful preparation...
Three-axes spectrometers (TAS) are considered one of the most flexible and versatile instruments for inelastic neutron scattering measuring fundamental excitations (phonons, magnons, and crystalline electric field) in materials with sub-meV energy resolution. However, the limitation of a three-axes spectrometer usually comes from the restriction of a point-by-point measurement strategy in the...
HEiDi is a versatile single crystal diffractometer using unpolarized thermal and hot neutrons to provide users worldwide with high quality structure data. The applications range from studies on various magnetic compounds [Maity2021, Dutta2023, Zobkalo2023] and new battery materials [Redhammer2021] to complex framework structures [Lotti2023].
Heidi’s high neutron flux allows both studies up...
Superalloys are key materials of our modern society. They are not only used in harsh environments of power plants for energy conversion but also in aerospace or marine applications, as they combine excellent mechanical properties at high homologous temperatures with very good oxidation and corrosion resistance. To further improve the efficiency of engines, advanced superalloys with improved...
Neutron single crystal diffraction provides an experimental method for the direct location of hydrogen and deuterium atoms in biological macromolecules. At the FRM II neutron source the neutron single crystal diffractometer BIODIFF, a joint project of the Forschungszentrum Jülich and the FRM II, is mainly dedicated to the structure determination of enzymes. Typical scientific questions address...
Kagome magnet RMn6Sn6, [R=Gd-Er] are extensively studied in search of nontrivial magnetic and topological states [1,2]. The strong magnetic coupling in between the metal ion Mn in pristine Kagome bilayers and the rare earth R in triangular lattice framework generates the complex magnetic phases which are favorable for correlated topological states [3,4]. Here in this work, the pressure...
Mesoporous transition metal oxide has attracted a lot of interest due to its excellent properties. Block copolymers with sol-gel is one of the popular approaches to fabricate mesoporous transition metal oxides. In this work, titania thin films are synthesized with the sol-gel method templated by a diblock copolymer. A similar morphology transition, from worm-shaped mesopores to ordered...
The lithium garnet Li7La3Zr2O12 (LLZO) is a leading solid state electrolyte candidate for an All-solid-state battery (ASSB) containing Li as anode because of its high ionic conductivity, high toughness and wide electrochemical stability. Undoped LLZO exists in two polymorphic phases; a low conductivity tetragonal phase and a high conductivity cubic phase. Dopants in LLZO play a critical role...
The Data Evaluation Group DEVA at MLZ is a team of scientists with many years of experience in selected neutron and X-ray methods. DEVA was established in 2022 with the goal of guiding and actively supporting the user community, with a focus on new users. This includes data analysis and data reduction, assistance in extracting further knowledge from the acquired data, and support in the...
Within the DAPHNE4NFDI project the MLZ is enganged in establishing a datacalougue to foster FAIR access to the data produced at the MLZ.
We will give an overview over the technical aspects of the implementation of such a catalogue at MLZ.
KWS-3 is a very small angle neutron scattering diffractometer operated by JCNS at Heinz Maier-Leibnitz Zentrum (MLZ) in Garching, Germany. The principle of this instrument is one-to-one imaging of an entrance aperture onto a 2D position sensitive detector by neutron reflection from a double-focusing toroidal mirror. In current state, KWS-3 is covering Q-range between 3·10-5 and 2·10-2 Å-1 and...
Binders play an important role in multi-component electrodes for rechargeable batteries, which suffer from poor electronic and ionic conductivity. Binder-free electrodes provide another way to resolve problems, where sophisticated structure construction is required. A new concept of electrode processing alternative to binder-containing and binder-free electrodes was established. A...
Hydrated proteins undergo a dynamical transition (DT) at Td ≈ 200 K. The transition is associated with the activation of protein dynamics on the ps-ns time scale, suitably detected by Elastic Incoherent Neutron Scattering (EINS). The DT has been also observed in other biomolecules and is deemed necessary for biological functionality. Surprisingly, a DT has been recently found in a...
Over the past several years, the Sample Environmental group at Julich Centre for Neutron Science (JCNS) at MLZ has made remarkable progress in updating and maintenance of the old cryogenic equipment and introducing the new ones. In addition to the tradition Orange-type wet cryostats, several cryogen-free closed cycle cryostats are in use. MLZ offers a wide range of dry and wet magnets with...
High-precision measurements of angular correlations in neutron beta decay address a number of questions which are at the forefront of particle physics. For a new generation of beta decay experiments, like the PERC (Proton Electron Decay Channel) experiment currently under construction in Munich, frequency-based beta spectroscopy methods using the cyclotron radiation emitted by electrons in a...
In addition to state-of-the-art neutron scattering instrumentation, sample environment is another important pillar to attract the user community.
On this occasion, new devices and developments will be presented such as closed cycle refrigerators with temperature extension up to 1.5K, development of high-pressure equipment for SANS, progress in automatic sample exchange systems and the new...
A low-energy monoenergetic positron beam can be used to implant positrons near the surface of materials. In polymers and in particular in porous materials positrons can form positronium (Ps). Even at greater implantation depths Ps can diffuse back to the surface and be emitted if the material has an open porous structure, i.e., the pores create a path to the outside. Therefore, we can...
BornAgain [1,2] is an open-source software package to model and fit SAS, GISAS, off-specular scattering, and reflectometry. It was designed to fully reproduce the functionality of the standard software IsGisaxs [3], allow for hierarchical sample models of arbitrary complexity, and support neutron polarization and magnetic scattering. It can be used either through a graphical user interface or...
Inelastic neutron scattering is very useful experimental method used across all scientific fields. It is mainly used for uncovering the dynamics and excitations in single crystals. Although very powerful method inelastic neutron scattering suffers from low flux scattered from sample. This can be improved by increasing volume of sample.
Traditionally, experimental physicist are coaligning...
The “Stress and TExture CAlculator” (Steca) is a data reduction software tool. It is used to support the analysis of the data from x-ray material diffractometers and neutron strain scanner STRESS-SPEC.
In particular, peak positions, widths and intensities are extracted from the 2D detector data of the instruments. The extracted data can be saved within a Steca project file or exported into...
Tuning hydrostatic pressure up to moderate (P < 1000 bar) pressure values can be crucial for understanding structure-property interplay in different disciplines, including: protein treatment in food processing, biophysics of deep-sea, processing of baroplastic polymers, polymer coating technologies for artificial joints. To the best of our knowledge, the role of pressure and thermodynamic...
The Automatic Laue Sample Aligner (ALSA) uses a robotic arm (Mecademic Meca500 [1]), computer vision [2], and air suction to manipulate small crystal samples.
While controlling the robot arm, operating with the absolute reference frame of the robot would be quite confusing for the end user. Therefore, taking inspiration from Entangle [3] implementation, we have written a control driver using...
The salt effect of KCl on D2O hydration and subsequent thermoresponsive behavior of diblock copolymer (DBC) thin films, which feature a short zwitterionic poly(4-((3-methacrylamidopropyl) dimethylammonio) butane-1-sulfonate)) (PSBP) block and a long nonionic thermo-responsive poly(N-isopropylmethacrylamide) (PNIPMAM) block, is studied by in situ spectral reflectance (SR) and time-of-flight...
Polarized neutron diffraction is a powerful tool for studying condensed matter physics and to probe the spin and orbital properties of unpaired electrons. POLI is a polarized neutron single crystal diffractometer built on the hot neutron source at MLZ. Currently three standard setups are implemented on POLI: 1) zero-field spherical neutron polarimetry using CRYOPAD; 2) polarized neutron...
Poly(2-oxazoline)s are biocompatible polymers featuring high copolymerization versatility and low in-vivo immunogenicity [1]. Thus, the system has potential in biomedical applications. While linear poly(2-oxazoline) homo- and block copolymers have been amply studied, studies on molecular brushes from poly(2-oxazoline)s are still scarce [2, 3]. In the present study, we investigate molecular...
Lithium has a high specific capacity of 3860 mAh g−1 and a low electrochemical potential (-3.04 V), promising a high energy density lithium metal battery (LMB). However, the growth of lithium dendrites during charging and discharging would penetrate the separators in LMBs, which leads to short circuit. To inhibit the growth of lithium dendrites, we focus on optimizing the SEI layer through...
All-solid-state lithium-ion batteries (ASSLIBs) have received extensive attention as one of the most promising power sources for flexible and wearable electronics, mainly because of their high flexibility, high energy density and reliable safety. However, the practical application of ASSLBs has been hindered by the poor interfacial stability and inferior ionic conductivity. Solid polymer...
The integration of sample environment (SE) equipment in a beam line experiment is a complex challenge both in the physical world and in the digital world. Different experiment control software offer different interfaces for the connection of SE equipment. Therefore, it is time-consuming to integrate new SE or to share SE equipment between facilities. To tackle this problem, the International...
Stimuli-responsive diblock copolymers (DBCPs) have gathered considerable interest for uptake, delivery and release processes due to their property tunability upon exposure to external stimuli, such as temperature and light. In this study, DBCPs comprising PNIPAM as the thermoresponsive block and azopyrazole (AzPy) functionalized PNDMAM as the photo-responsive block are expected to feature dual...
In the rapidly evolving landscape of experimental research, the integration of advanced technologies has conducted in a new era of precision and efficiency. Robotic systems, supported by artificial intelligence, have become important tools for conducting experiments with high levels of control and accuracy. Among these rapid developments, the closed-loop approach stands out as a paradigm...
Our work focuses on the development of an Automatic Laue Sample Aligner (ALSA) that allows to increase
the sample size for neutron experiments, by fully automating the co-alignment process [1].
However, the sample manipulation, which utilizes a precise robotic arm (Mecademic Meca500 [2]),
requires also advanced use of computer vision (CV). This poster presents our integration of general...