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Design and implementation of advanced membrane formulations for selective transport of ions and molecular species are critical for creating the next generations of fuel cells and separation devices. this website It is necessary to understand the detailed transport mechanisms over time- and length-scales relevant to the device operation, both in laboratory models and in working systems under realistic operational conditions. Neutron scattering techniques including quasi-elastic neutron scattering, reflectivity and imaging are implemented at beamline stations at reactor and spallation source facilities worldwide. With the advent of new and improved instrument design, detector methodology, source characteristics and data analysis protocols, these neutron scattering techniques are emerging as a primary tool for research to design, evaluate and implement advanced membrane technologies for fuel cell and separation devices. Here we describe these techniques and their development and implementation at the ILL reactor source (Institut Laue-Langevin, Grenoble, France) and ISIS Neutron and Muon Spallation source (Harwell Science and Technology Campus, UK) as examples. We also mention similar developments under way at other facilities worldwide, and describe approaches such as combining optical with neutron Raman scattering and x-ray absorption with neutron imaging and tomography, and carrying out such experiments in specialised fuel cells designed to mimic as closely possible actualoperandoconditions. These experiments and research projects will play a key role in enabling and testing new membrane formulations for efficient and sustainable energy production/conversion and separations technologies.Measurements of fluorescence intensity of the hydrophobic pyridinium salt (DTPSH) remaining in the organic phase after partition experiments in the DCM/H2O system allowed an approximate method to be developed to estimate the mean number of molecules (N = 942) on the surface of 22.8 nm gold nanoparticles and the separation (1.89 nm) between these organic molecules. This protocol is based on the ability that the organic molecules possess to coat the surface of the nanoparticle, which can migrate from the organic to the aqueous phase as a result of the driving force of the strong binding of sulfur to gold. To validate our estimation, we used a projection of the results obtained by Wales and Ulker to solve the Thomson problem, a mathematicians' challenge, used as a model to calculate the mean distance (1.82 nm) separating particles on the surface, in excellent agreement with the results obtained by our method. The quality of results, the simplicity of calculations, the low fluorescence detection limit, and the inexpensive materials, recommend this procedure for rapid estimates of the mean number of molecules on the surface of nanoparticles.Hybrid supercapacitors (SCs) made of carbon-metal oxide composites are devices which combine the advantages of electric double layer capacitors and pseudocapacitors viz high energy density, high power density and high cyclability. This is best achieved when the pseudocapacitive components are uniform in size and distribution on the conducting carbon support. Electrodes mats, fabricated from carbonized electrospun fibers generated from solutions of polyacrylonitrile (PAN) as the carbon source, cobalt (III) acetylacetonate as a metal oxide precursor, and polymethacrylic acid (PMAA) as a metal oxide precursor carrier were utilized in coin cell SCs. Fibers without the PMMA carrier were prepared for comparison. XRD and TGA showed conversion of the cobalt precursor to a mixture of cobalt and cobalt oxide (Co3O4). When the PMAA carrier was used, specific capacitance increased from 68 F g-1in PAN-Co3O4to 125 F g-1in PAN-PMAA-Co3O4. The addition of PMAA to the system results in better uniformity, accessibility and dispersion of metal and metal oxide particles. Due to the relatively low surface area of carbonized samples, Co3O4nanoparticles are the primary contributors to charge storage. The fabricated fibers show an energy density of 8.9 at 750 W kg-1, which is twice that of the fibers made without PMAA.Black arsenic phosphorus single crystals were grown using a short-way transport technique resulting in crystals up to 12 x 110 μm and ranging from 200 nm to 2 μm thick. The reaction conditions require tin, tin(IV) iodide, grey arsenic, and red phosphorus placed in an evacuated quartz ampule and ramped up to a maximum temperature of 630 °C. The crystal structure and elemental composition were characterized using Raman spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy, cross-sectional transmission microscopy and electron backscatter diffraction. The data provides valuable insight into the growth mechanism. A previously developed b-P thin film growth technique can be adapted to b-AsP film growth with slight modifications to the reaction duration and reactant mass ratios. Devices fabricated from exfoliated bulk-b-AsP grown in the same reaction condition as the thin film growth process are characterized, showing an on-off current ratio of 102, a threshold voltage of -60 V, and a peak field-effect hole mobility of 23 cm2/V·s at Vd=-0.9 V and Vg=-60 V.Type-I heterostructure, in which electrons and holes are confined in same region, is widely used in light emitting diodes and semiconductor lasers. Type-II heterostructure is widely used in photovoltaic devices because of its excellent spatial separation property of electrons and holes. Can we integrate photovoltaic, photoelectric properties with luminescent property in one device? Here we report a van der Waals heterostructure formed by black phosphorus (BP) and SnS monolayers. It is expected to realize these functions in one device. By first-principles methods, the structural stability, electronic properties and optical properties are investigated. It was found that the BP/SnS bilayer is type-II heterostructure with an indirect bandgap of 0.56 eV. Thep-like character of the band edge in BP/SnS vdW heterostructure makes it to be an excellent optoelectronic material. The type-II stability of the system can be improved by applying a negative electric field. However, when the positive electric field is bigger than 0.