A5043819152- Nuclear Physics and Applications
- Block Copolymer Self-Assembly
- Advanced Polymer Synthesis and Characterization
- NMR spectroscopy and applications
- Rheology and Fluid Dynamics Studies
- Thin-Film Transistor Technologies
- Material Dynamics and Properties
- Animal Behavior and Reproduction
- Supramolecular Self-Assembly in Materials
- High-pressure geophysics and materials
- Magnetic properties of thin films
- Polymer Surface Interaction Studies
- melanin and skin pigmentation
- Embedded Systems and FPGA Design
- Liquid Crystal Research Advancements
- Insect and Arachnid Ecology and Behavior
- Digital Holography and Microscopy
- Silicon and Solar Cell Technologies
- MXene and MAX Phase Materials
- Silicon Nanostructures and Photoluminescence
- Seaweed-derived Bioactive Compounds
- Reproductive biology and impacts on aquatic species
- Heusler alloys: electronic and magnetic properties
- Nanofabrication and Lithography Techniques
- Dendrimers and Hyperbranched Polymers
Institut Laue-Langevin
2013-2025
Université Grenoble Alpes
2015-2025
Institut de Biologie Structurale
2015-2025
Uppsala University
2013-2021
University of Sheffield
2010-2020
Technische Universität Berlin
2016-2017
Using neutron reflectivity, self-stratification in a model P3HT/PCBM blend is observed. The as-spun and solvent-annealed films show depletion of PCBM near the top surface enrichment at substrate (see figure). Depletion cathode interface photovoltaic device could act as barrier to efficient electron extraction. On thermal annealing, depleted region eliminated; an effect that partially explains improvement devices on annealing.
A new neutron reflectometer SuperADAM has recently been built and commissioned at the Institut Laue-Langevin, Grenoble, France. It replaces previous ADAM. The instrument uses a solid state polarizer/wavelength filter providing highly polarized (up to 98.6%) monochromatic flux of 8 × 104 n cm−2 s−1 with monochromatization Δλ/λ = 0.7% angular divergence Δα 0.2 mrad. includes both single position sensitive detectors. detector allows simultaneous measurement specular reflection off-specular...
Abstract Eurasian Jay ( Garrulus glandarius ) feathers display periodic variations in the reflected colour from white through light blue, dark blue and black. We find structures responsible for are continuous their size spatially controlled by degree of spinodal phase separation corresponding region feather barb. Blue have a well-defined broadband ultra-violet (UV) to wavelength distribution; nanostructure has characteristic morphology with lengthscale order 150 nm. White regions larger 200...
Using isotope contrast, neutron reflectivity was applied to evaluate the amounts of water and ethanol intercalated into a graphene oxide membrane from pure binary vapors selectivity permeation.
Abstract Cyphochilus beetle scales are amongst the brightest structural whites in nature, being highly opacifying whilst extremely thin. However, formation mechanism for voided intra-scale structure is unknown. Here we report 3D x-ray nanotomography data chitin networks of intact white and Lepidiota stigma . Chitin-filling fractions found to be 31 ± 2% 34 1% , indicating previous measurements overestimated their density. Optical simulations using finite-difference time domain morphologies...
The Super ADAM reflectometer—a part of Collaborative Research Group at ILL—is modern competitive neutron research platform which is destined primarily for Swedish use (70% total beam time). Supe...
Abstract Enabling control over macromolecular ordering and the spatial distribution of structures formed via mechanisms molecular self-assembly is a challenge that could yield range new functional materials. In particular, using minimalist peptides, to drive incorporation large complex molecules will allow functionalization strategy for next generation biomaterial engineering. Here, first time, we show co-assembly with increasing concentrations highly charged polysaccharide, fucoidan,...
Neutron scattering techniques offer several unique opportunities in materials research. However, most neutron experiments suffer from the limited flux available at current facilities. This limitation becomes even more severe if time-resolved or kinetic are performed. A new method has been developed which overcomes these limitations when a reversible process is studied, without any compromise on resolution beam intensity. It demonstrated that, by recording absolute time detector events linked...
All-Heusler multilayer structures have been investigated by means of high kinetic x-ray photoelectron spectroscopy and magnetic circular dichroism, aiming to address the amount disorder interface diffusion induced annealing structure. The studied multilayers consist ferromagnetic Co$_2$MnGe non-magnetic Rh$_2$CuSn layers with varying thicknesses. We find that begins already at comparably low temperatures between 200 $^{\circ}$C 250 $^{\circ}$C, where Mn appears be most prone diffusion. also...
Shear responsive surfaces offer potential advances in a number of applications. Surface functionalization using polymer brushes is one route to such properties, particularly the case entangled polymers. We report on neutron reflectometry measurements solutions performed under controlled shear as well coarse-grained computer simulations corresponding these interfaces. Here we show reversible and reproducible collapse brushes, increasing with rate. Using two greatly different chain lengths...
We have applied small angle scattering in grazing incidence beam geometry on a time-of-flight neutron instrument. Due to the broad wavelength distribution provided for specific incident penetration depth of is varied over range single measurement. The near surface structure polymer micelles close silicon substrates with distinct energy resolved. It observed that very near-surface strongly depends coating whereas further away from bulk like ordering found. A more pronounced found surfaces high energy.
Amphiphilic block copolymers within a range of volume fraction spontaneously form vesicles in aqueous solution, where water core is enclosed by polymer bilayer. Thin-film rehydration method used to produce routinely; thin film immersed water, the swells, and are formed which bleb off from surface. We have studied early stages hydration for PEO–PBO copolymer films under controlled vapor conditions understand this formation mechanism so enable more efficient ways encapsulate molecules using...
We apply specular and off-specular neutron reflection at the hydrophobic silicon/water interface to check for evidence of nanoscopic air bubbles whose presence is claimed after an ad hoc procedure solvent exchange. Nanobubbles and/or a depletion layer hydrophobic/water have long been discussed generated plethora controversial scientific results. By combining reflectometry (NR), (OSS) grazing incidence small angle scattering (GISANS), we studied between hydrophobized silicon heavy water...
Neutron reflectometry is a powerful tool used for studies of surfaces and interfaces. The absorption in the typical studied materials neglected this technique limited only to reflectivity measurement. For strongly absorbing nuclei, can be directly measured by using neutron-induced fluorescence which exploits prompt particle emission isotopes. This emerging from soft matter biology where highly very small quantities, are as label buried layers. Nowadays, importance layers rapidly increasing,...
Neutron and X-ray reflectometry were used to determine the layer structure hydrogen content of thin films amorphous silicon (a-Si:H) deposited onto crystalline (Si) wafers for surface passivation in solar cells. The combination these two techniques is well suited non-destructive probing a-Si:H due being able probe buried interfaces having sub-nanometer resolution. also unique its ability allow determination density gradients light elements such as (H). neutron scattering contrast between Si...
Abstract High resolution X-ray nano-tomography experiments are often limited to a few tens of micrometer size volumes due detector size. It is possible, through the use multiple overlapping tomography scans, produce large area scan which can encompass sample in its entirety. Mounting and positioning regions be scanned highly challenging normally requires focused ion beam approaches. In this work we have imaged intact beetle scale cells mounted on tip needle using micromanipulator stage. Here...
Graphite intercalation compounds (GICs) are a group of layered materials that suitable as monochromators for cold neutrons. KC24 is particularly interesting compound in this regard it features large c-axis lattice spacing 8.74 Å, high reflectivity, and the possibility to produce crystals with mosaicity matches beam divergence neutron guides. GICs can be synthesized different levels intercalation, known stage compounds. Each displays specific d-spacing. Impure GIC-monochromators containing...