A modified quenching and deformation dilatometer (TA instruments DIL 805A/
D/T) is now in operation at the Heinz Maier-Leibnitz Zentrum (MLZ, Germany)
neutron center. It is customized for running neutron scattering measurements
during the temperature/deformation treatment of the sample, in particular
neutron diffraction (phase, texture, and lattice strain) and neutron small...
Interfaces based on metal oxides play a major role in functional materials for energy applications. For example, TiO2 can serve as a photocatalyst in the production of hydrogen or as an anode material in emerging solar cell and battery technologies. In most applications, a designed structure is highly de-sired to fulfill performance conditions on different length scales. Moreover, devices...
For the mechanical characterization of the adhesive bond of pressure-sensitive adhesives one has to take into account the geometry of the adherents and the kind of stress applied. We present a technique, which is especially adapted for the measurement of tack for assemblies of fibers coated with pressure-sensitive adhesives using customized cylindrical composite stamps [1]. Key element of the...
The PERC facility is currently under construction at the MEPHISTO beamline of the FRM II. 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...
Au/TiO2 nanohybrid materials have attracted significant attention due to the outstanding optical, photocatalytic and photovoltaic performance. We use customized polymer templating to achieve TiO2 nanostructures with different morphologies. Au/TiO2 hybrid thin films are fabricated by sputter deposition. An in-depth understanding of the Au morphology on the TiO2 templates is achieved with in...
Fast neutrons offer high penetration capabilities for both light and dense materials due to their comparatively low interaction cross-sections, making them ideal for the imaging of large-scale objects such as as-built plane turbines, for which X-rays or thermal neutrons do not provide sufficient penetration. However, inefficient fast neutron detection limits the widespread application of this...
Metal alloys as anode material for lithium ion batteries such as LiAl offer a high theoretical capacity in relation to their low cost. Compared to the conventional graphite anode, aluminium has an almost three times higher specific capacity with 993 mAh/g. During lithiation, aluminium first forms a solid solution with lithium called the alpha-LiAl phase until the solubility limit is reached....
The sodium superionic conductor (NASICON) materials have been a widely studied class of solid electrolytes for Na-ion based all-solid-state batteries due to their high conductivity and facile synthesis conditions. The aim of this work is to elucidate the reason for extremely high conductivity exhibited by some compositions, specifically by $\text{Na}{1+x} \text{Zr}{2} \text{Si}_{x}...
The new VDM® Alloy 780 is a Ni-based superalloy developed for higher service temperatures than the widely used alloy 718, consisting of γ matrix, γ´ hardening phase, and δ & η high-temperature phases. Depending on the respective heat treatment of VDM® Alloy 780, various microstructures with different phase proportions can be obtained, which determine the mechanical properties of the alloy over...
Colloidal quantum dots (CQDs) have generated great interest in various optoelectronic devices because of their size-tunable bandgap, low-temperature solution processability. Lead sulfide (PbS) CQDs, with a strong absorption coefficient and large Bohr radius, enable solar cells to harvest infrared photons of the solar spectrum beyond the absorption edge of crystalline silicon and perovskites....
Perovskite solar cells (PSCs) are one of the most promising photovoltaic technologies and reached a certified 25.2% efficiency owing to their tuneable bandgap, high carrier mobility, long diffusion length and so on. The long-term operational stability of PSCs, however, has been not investigated. Herein, we probe the structure change with grazing-incidence small-angle scattering techniques...
The combination of dimethyl sulfoxide (DMSO)-solvent doping and physical-chemical DMSO/salt de-doping in a sequence has been used to improve the thermoelectric (TE) properties of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) films. A high power factor of ca.105.2 µW m-1 K-2 has been achieved for the PEDOT:PSS film after post-treatment with 10 % sodium sulfite (Na2SO3)...
Gold deposition via high power impuls magnetron sputtering (HiPIMS) allows to coat thin metal layers on heat sensitive materials allowing increased adhesion compared to an evaporated gold layer. In addition, this particular technique allows deposition at a lower deposited thermal energy. However, the low temperature nucleation and growth processes of HiPIMS are not sufficiently known....
In the past few years, perovskite solar cells (PSCs) received a lot of awareness in research due to their low manufacturing cost, high efficiency, and high specific power. For industry, PSCs are very interesting because of their easy solution-based fabrication process and comparable efficiencies with the established c-Si-based solar cells.[1] Thus, the fabrication can be upscaled...
ZnO has received much attention over the past years because it has a wide range of properties, including high transparency, piezoelectricity, wide-bandgap semiconductivity, high electron mobility and low crystallization temperature. To improve the photovoltaic performance of ZnO-based hybrid solar cell devices, an interconnected mesoporous inorganic nanostructure is favorable, which can...
Hybrid plasmonic nanostructures have raised great interest for being used in a variety of optoelectronic devices, due to the surface plasmon resonance (SPR). Charge carriers trapped in colloidal quantum dots (QDs) at localized surface defects is a key issue in photodetectors. Self-assembled hybrid metal/quantum dots can couple plasmonics and quantum properties to photodetectors and modify...
Developing clean energy lies the heart of sustainable development of human society. Triboelectric nanogenerator (TENG) originating from Maxwell’s displacement current is a new type of energy harvester for harnessing ambient mechanical energy based on the coupling of triboelectrification and electrostatic induction effect. Compared with other counterparts, owing to the light-weight, low-cost,...
Rechargeable lithium metal batteries have been recognized one of the most promising energy storage devices due to their superior energy density. However, serious safety concern and poor cyclability are featured originating from uncontrolled lithium dendrite growth and unstable solid electrolyte interface (SEI) layer. One strategy to suppress dendrite growth is surface modification with...
Nickel manganese spinel LiNi0.5Mn1.5O4 is considered one of the most promising cathode materials for lithium-ion batteries. On the one hand, this is because of its high energy density due to its high voltage plateau at 4.7 V, and the high rate capability due to its three dimensional diffusion network in the cubic crystal system. On the other hand, this material is interesting because...
Thin film samples for neutron investigation can be fabricated with a Molecular Beam Epitaxy (MBE) setup on site. The MBE setup is part of the additional facilities which can be booked in combination with a neutron instrument proposal at MLZ. Discuss your ideas with the thin film lab staff and then write a proposal. There are two options for access: In remote access the thin film staff...
Last years, interest in the Dy/Co system has increased, since it became possible to switch the magnetization of the system without applied magnetic field by means of a femtosecond laser pulses. Important requirements for achieving switchable magnetic films are antiferromagnetic coupling between spins of rare-earth and transition metals and perpendicular magnetic anisotropy (PMA). Therefore, it...
supper mirror(SM) arrays to greatly reduce stray magnetic fields by using self compensation. This yoke is a minor modification to the typical existing magnetic yokes used for polarized SM arrays, often consisting of rows of very strong permanent magnets, such as NbFeB, arranged on either side between a cavity made of a pair of thick (> 1 cm) soft iron plates. Such configurations can produce...
Molecular dynamics simulations are an important tool in evaluating scattering data. They have a high potential, which is even further increasing with the ever increasing computation power and isn't yet fully exploited. For some systems, reliable simulations are already available that are compatible with measured data. For other systems, however, the agreement between simulation and experiment...
The implementation of decommissioning tasks requires accurate radiological characterization to be accomplished. Often, computational codes are used to complement experimental radiological characterization campaigns. These activation codes need accurate knowledge of elemental composition of non-irradiated materials. Besides determination of most nuclides by the well-established Inductively...
Cellulose nanofibrils (CNF), extracted from wood, are sustainable materials par excellence and used to fabricate high-strength materials. A promising route for fabricating porous CNF films on large scale is spray deposition using water-based technologies; the resulting porous CNF templates are excellent candidates to infiltrate conductive polymers and plasmon-active nanoparticles for...
Co-nonsolvency occurs if a mixture of two good solvents causes the collapse or demixing of polymers into a polymer-rich phase in a certain range of compositions of these two solvents. The nonionic thermo-responsive polymer, poly(isopropylmethacrylamide) (PNIPMAM), which features a lower critical solution temperature (LCST) in aqueous solution, has been widely used to investigate its collapse...
Thermoresponsive polymer thin films have gained a lot of attention in the past decades due to their attractiveness for a wide range of applications. A variety of polymer showing LCST- or UCST-type behavior are known, and their transition temperatures can be influenced by various factors such as molar mass, end groups, copolymerization, or by the addition of salts. For polymers in aqueous...
Lately, organic solar cells (OSCs) have gained increasing attention due to their rapidly increas- ing efficiencies as well as the relatively easy scalability in their manufacture. However, their production relies heavily on the use of halogenated solvents, as organic solar cells made with environmentally friendly solvents often suffer from reduced performance, which is associated with the...
Cooperative dehydration is a major driving force for the demixing transition in poly(N-isopropylacrylamide) (PNIPAM), causing the polymer chains to collapse at the cloud point, followed by aggregation in aqueous solution. The motion of the hydration water is slowed down compared to bulk water and it is crucial in the solvation behavior in the presence of a co-solvent such as methanol. QENS...
Nanoscale assemblies in water of novel thermoresponsive and double hydrophilic poly(N-isopropylacrylamide)-block-poly(oligo ethylene glycol methyl ether acrylate) (PNIPAM-b-POEGA) copolymers have been investigated by synergy of Fourier transform infrared (FTIR) spectroscopy and small angle neutron scattering (SANS) experiments. By focusing on the influence of temperature as external stimulus...
In this work, we present a combined analysis of small angle neutron scattering (SANS), linear rheology and neutron spin eco (NSE) spectroscopy experiments on the supramolecular association and chain structure of supramolecular polymer blends. These consist of well-defined hydrogenated (H) polymers with a polyethylene oxide (PEO) backbone carrying the directed homocomplementary hydrogen-bonding...
Functional nanocomposites are an important class of smart and adaptive materials. They offer a broad application range from sensors through stretchable electronics to energy conversion and human health. Especially, responsive materials which are able to perform self-assembly in different environments (e.g. magnetic field) are in the center of interest. Further developments in this area would...
Graphite and materials made of graphite have historically been of huge technological importance due to their manifold interesting properties. High performance lithium-ion batteries (LIBs) typically use graphite-based anode materials. The energy storage is achieved through the reversible reaction of the graphite with lithium ions in an electrochemical intercalation reaction. When the material...
We are investigating the crystal structure and properties of inverse perovskite nitrides with elpasolite-type superstructures. This superstructure is due to a full or partial ordering of nitrogen atoms and defects on the perovskite $B$ site. Since nitrogen scatters neutrons much more strongly than X-rays, neutron diffraction measurements of seven compounds with this superstructure were...
Perovskite solar cells (PSCs) have attracted increasing attention in research and industry due to their high efficiency, low material cost and simple solution-based fabrication process, which allow the manufacture of thin, flexible photovoltaic modules.
In laboratory devices, the efficiency already exceeds 25% and is comparable with c-Si.[1] However, one of the most important steps towards...
