Since the first suite of neutron scattering instruments was commissioned in 2008 the Australian Nuclear Science and Technology Organisation (ANSTO) has invested in instrumentation for the analysis of thin interfacial films. The horizontal time-of-flight reflectometer, Platypus, has now been joined by an X-ray reflectometer and a variable angle spectroscopic imaging ellipsometer. The high...
Ultra-small and small and angle neutron scattering (USANS and SANS) are versatile techniques for investigating the micro and nanoscale structure of materials such as food, surfactants, polymers, colloids, metals, minerals, and emulsions. These techniques have been exceptionally useful for studying complex materials of industrial importance in recent years. Various examples have emerged where...
We report the completion of the deployment project to incorporate neutron polarisation analysis capabilities on 6 ANSTO instruments. The instruments include high-intensity diffractometer WOMBAT, SANS QUOKKA, thermal triple-axis spectrometer TAIPAN, cold triple-axis spectrometer SIKA, cold neutron chopper spectrometer PELICAN, and reflectometer PLATYPUS (for off-specular scattering). We can now...
5% Co-TiO2 film has been deposited using pulsed laser deposition. By delicately controlling deposition parameters, nanoclusters of Co are formed in the interface, confirmed by transmission electron microscopy, energy dispersive spectroscopy and X-ray absorption near edge spectroscopy. The film exhibits a very high saturation magnetization measured by magnetometer, equivalent to 6.54 μB/Co,...
In soft matter and life science neutron scattering experiments, access to full or partially deuterated materials is critical. Such molecules may include proteins, lipids, fatty acids, small molecules, membranes and so on. These classes of molecules are of intense interest to the neutron research community, however they are often not used due to various reasons, including: deuterated molecles...
Li-rich xLi2MnO3·(1−x)Li[NiaCobMnc]O2 (a+b+c=1) cathode materials are promising candidates for lithium-ion batteries owing to their high practical capacity (250-280 mAh/g). But its practicality is hindered due to the intrinsic voltage fade, large irreversible capacity loss, low rate capability, and structural instability issues. Elemental doping strategies are already shown to be effective in...
Nanostructured gold electrodes have attracted immense interest for a broad range of applications, especially in biosensing due to their unique biocompatibility, stability, sequence dependent adsorption of nucleic acids, and high throughput optical and electrochemical responses. Integration of tuneable mesopores into gold electrodes offers high surface area with voluminous active sites for...
EMU, the high-resolution neutron spectrometer installed at the OPAL reactor, ANSTO [1] delivers 1 μeV FWHM energy transfer resolution for an accessible ± 31 μeV energy transfer range. The spectral resolution is achieved by neutron backscattering from Si (111) on the primary and second flight paths, which also determines the accessible 0.35 to 1.95 Å^-1 momentum transfer range.
Two years of...
Layered RT2X2 compounds (R = rare-earth, T = 3d, 4d transition metal, X = Si, Ge) of tetragonal body centred ThCr2Si2 –type structure (I4/mmm) are among the most widely studied systems in condensed matter science [e.g. 1]. Yb- and Eu-based intermetallics are of particular interest due to their intermediate valence character and unusual physical and magnetic properties [e.g. 2, 3]. While...
Mixed conductors – materials that exhibit significant mobility of more than one type of charge carrier such as oxide ions, protons and electrons – have a range of important applications including solid oxide fuel cell membranes, electrodes, batteries and sensors. We recently studied the behaviour of hydrogen in the mixed ionic-electronic conductors γ-Ba$_4$Nb$_2$O$_9$ and 6H-Ba$_4$Ta$_2$O$_9$,...
Research on thermoelectric (TE) materials have been an active field for the past decade as TE material can potentially be used to capture and recycle waste-heat into electricity. Significant developments have been achieved in the search for the next-generation of advanced thermoelectrics that could play an increasing role in sustainable technology. One of the strategies in improving the...
Antimicrobial peptides (AMPs) have been widely investigated because of their potential solution to the encroaching ‘antibiotic crisis but information about mechanism of action of the peptides is still scarce [1]. Bacterial cell membranes will always be the initial point of contact for AMPs due to electrostatic interactions between the anionic molecules on the bacterial cell surface and the...
The interaction of cinnamic acid (CA) and its analogues viz. p-coumaric acid (PCA) and caffeic acid (CFA) with core-shell micelles of a moderately hydrophobic Pluronic® P123 has been investigated using cloud point (CP), viscosity, dynamic light scattering (DLS), small-angle neutron scattering (SANS) and steady-state fluorescence measurements. These solubilizates alter micellar behaviour of...
Over the last decade layered-honeycomb oxides have come to increasing prominence as materials that exhibit an array of interesting properties, including use as electrodes for Li-ion batteries, high electrical conductivity, low temperature magnetic phases, and spin-glass transitions. Layered oxides with the general formula AxM2XO6 (A = Li, Na; M = transition metals eg. Co, Cu, Ni; X = Bi, Sb,...
Key words: lithium ion batteries, battery safety, output voltage, LiNi0.5Mn1.5O4//Li4Ti5O12 full battery, AlF3 coating, in-operando, neutron powder diffraction, electrochemical performance
Lithium ion batteries (LIBs) with graphite anodes and LiCoO2 cathodes have been widely used in our daily life. Since the operating voltage of graphite is close to that of the metal lithium dendrite...
Residual stresses induced in the fabrication of steel components may lead to distortion and a significant loss of strength in a steel structure. Accordingly, research on the residual stress distribution in steel sections is becoming an important consideration in steel structural analysis. The characteristics of residual stresses in hot-rolled and welded mild steel sections have been...
Magnetite (Fe3O4), the oldest known magnet, is still a hotly debated material in scientific research, due to its complex magnetic, electronic and transport properties. One of the most interesting physical phenomena associated with Fe3O4 is the occurrence of a metal-insulator transition at ~120 K (TV), the so-called Verwey transition, which is associated to a charge ordering below TV,...
Inelastic neutron scattering experiments have been performed on a series of vanadates, in particular TbVO3 and CeVO3, to categorise the crystal field and magnetic excitations. The vanadates possess a configuration with corner sharing, distorted VO6 octahedra (space group Pbnm) with a collinear C-type antiferromagnetic structure occurring below Néel temperatures of TN = 110 K and 124 K...
The double-crystal ultra-small-angle neutron scattering (USANS) diffractometer KOOKABURRA at ANSTO was made available for user experiments in 2014. KOOKABURRA allows the characterization of microstructures covering length scales in the range of 0.1–10 µm. Use of the first- and second-order reflections coming off a doubly curved highly oriented mosaic pyrolytic graphite pre-monochromator at a...
Sodium-ion batteries (NIB) are of intense current interest as alternatives to lithium-ion batteries for large-scale applications in which kinetics and weight are not the primary consideration. However, the jury is still out on the ultimate competitiveness of NIB versus other energy storage solutions, with one major uncertainty being a lack of Na electrode materials. [1] Monoclinic Na4Ni7(PO4)6...
The structural and magnetic properties of MnCoGe-based alloys have been studied extensively in recent years due to their potential application as magnetic cooling materials based on the magnetocaloric effect (MCE). The Mn(Co$_{1-x}$Ni$_x$)Ge series is of particular interest as magnetic transitions in the range 275 K to 345 K generally coincide with a martensitic structural transition...
Artificially grown thin film heterostructures of transition metal oxides by far exceed the capabilities of current semiconducting technology as they offer additional functionalities such as metal-insulator transitions, magnetism, superconductivity, or multiferroicity. Bismuth ferrite (BiFeO3) is the rare case of a room temperature multiferroic material and offers as such the most promising...
Apart from the specialised but important application to phase determination, multiple scattering in single-crystal neutron diffraction is usually an undesirable source of error. The presence of multiple scattering for a particular Bragg reflection can be verified by performing an azimuthal scan, if the diffractometer offers that possibility, or by varying the wavelength. Either of these checks...
Lamellar liquid crystals consisting of water, para-xylene, and Triton X-100 were formulated and were examined as silica nanoparticles of differing size and surface chemistry were doped in. The particles, regardless of size, were found to likely migrate to the liquid crystal domain boundaries, where they influence the structural and rheological properties of the mesophase. Consequently, phases...
The implementation of polarisation analysis on a conventional time-of-flight spectrometer has been a major instrumental goal for some time. Here we present our recent results describing our successful test of the polarisation analysis option on the PELICAN spectrometer. The compact incident neutron polarisation system is an integration of a solid-state C-bender supermirror polariser with a...
Research into the development and understanding of photo-rheological fluid formulations has gained significant momentum in recent years due to their potential for widespread application in fields such as biomedicine, nanotechnology and oil drilling. Imparting of photo-controlled viscosity to a solution can be achieved by formation and destruction of elongated worm-like micelle surfactant...
For many years the triple-axis spectrometer has been utilised by for neutron scatters to study many areas of magnetism and condensed matter physics. With cold neutrons, a triple-axis spectrometer has the capability to investigate physical phenomena with high energy and momentum resolution. Whilst time-of-flight spectrometry, such as PELICAN, is advanced, the cold triple-axis spectrometer has...
Liquid crystals combine the short to medium range order of crystalline structures with the macroscopic flow properties of liquids. They are of interest because of these and other properties, including optical birefringence. The azobenzene functional group readily forms liquid crystalline phases, and is of interest because of its ability to reversibly switch between trans and cis (E/Z)...
Gravity thickeners operate by mixing slurry with polymer to produce flocculated aggregates which settle much faster than isolated particles. Applying low shear rates through rakes and sloped walls, flocculated aggregates densify, making them settle even faster. Direct observations of aggregate densification have been limited to light scattering and video analysis. However, current analysis...
Tethered Bilayer Membranes (TBMs) are a versatile system for studying models of the cell membrane bilayer architecture and form the basis of a number of medical nano-sensing devices. These systems are typically tethered to a conductive substrate to enable the electrical signal, indicating the functionality, of the device to be recorded. The fact that these devices operate fully immersed in...
Protein-polysaccharide complexes have been used in various food applications such as fat replacers, meat analogues [1], encapsulation of bioactive ingredients [2], and for enhancing foam and gel stability [3]. Studying these complexes at the microstructural level is important as a way to understand the origin of their functional and physicochemical characteristics [4]. β-Lactoglobulin (Blg)...
QUOKKA is a versatile small angle neutron scattering (SANS) instrument in operation at the Australian research reactor, OPAL [1]. SANS is a powerful techniques for structural characterisation require a minimum of special preparation. As a conventional 40 m pinhole instrument operating with a neutron velocity selector the instrument1 is capable of providing a statistical and non-destructive...
Here we present some recent developments on sample environment equipment at ACNS, which markedly improve the existing capabilities for a range of beamline instruments, leading to greater scientific outcomes and operational efficiency.
A six-position thermalised sample changer with tumbling capability, which avoids sedimentation and particle size separation in samples suspended in a medium,...
Here we present some recent developments on sample environment equipment at ACNS, which markedly improve the existing capabilities for a range of beamline instruments, leading to greater scientific outcomes and operational efficiency.
A six-position thermalised sample changer with tumbling capability, which avoids sedimentation and particle size separation in samples suspended in a medium,...
Welding is a foundational aspect of all large-construction industries, ensuring strong, sustainable connections. Due to its relative operational simplicity, welding has become the most important industrial process used for manufacturing of metal parts. Also, the insertion of welding in the context of additive manufacturing (AM) make the welding knowledge to be a great importance for the...
In magnetoelectrics (ME) magnetic ordering and electric polarization (EP) coexist. The ME effect is larger, if in these materials EP is of spin origin and the coupling is strong. This coupling can be utilized in applications such as MRAMs. Although technically important, the coupling mechanism is complicated. Two types of materials fulfill this requirement: (i) Type II multiferroics (ii)...
The purpose of the scientific computing support at ANSTO is to aid in the interpretation of both structural and dynamical data from the neutron scattering instruments using atomistic modelling calculations. Most of these calculations are done with ab initio scientific software packages based on Density Functional Theory, including VASP, WIEN2K, ABINIT, SIESTA, PHONON, and QUANTUM ESPRESSO,...
ANSTO successfully operates one Small Angle Neutron Scattering instrument QUOKKA and in January of year 2016 commenced user operation of the second SANS instrument, BILBY. The Bilby is the utilizing both, Time-of-Flight (ToF) and monochromatic capabilities.
The design (in particular, set-up of four choppers which uses idea of that for D33 instrument [2] at ILL) opens possibility to vary...
Micellization and microstructure of mixed micelles from mixtures of an anionic fluorocarbon surfactant sodium perflurooctanoate (NaPFO) and conventional anionic surfactant sodium oleate (NaOl) with cationic alkyl methyl-imidazolium based non-amphiphilic and amphiphilic ionic liquids (ILs) with different alkyl chain length (C4, C6, C8 and C10) and anions viz. chloride (Cl-), tetrafluoroborate...
Copper containing oxides hold a widespread research interest in inorganic fields due to the fascinating electronic and magnetic properties the compounds exhibit. In the Cu-Sb-O ternary system, CuSb2O6 is the most intensively studied compound [1], owing to its unusual structural and magnetic behaviour. Jahn-Teller distortions from the Cu2+ cause an axial elongation of the Cu-O octahedra to give...
Membrane formation is often listed as one of the key steps in the origins of life, since this enabled the first organisms control over the environment around their genetic material. Unilamellar liposomes are one of the simplest models available of cellular membranes, and we have used small angle neutron scattering and neutron spectroscopy to characterize their structure and dynamics...
The ability to express and purify insect odorant receptors (OrXs) and reconstitute them into artificial membranes such as liposomes and nanodiscs has paved the way for their use as recognition elements in biosensors and also to aid in structural and functional experiments. In this study, we have used surface characterization techniques including ellipsometry, quartz crystal microbalance with...
Miscibility Gap Alloys (MGA) are a new type of latent heat Thermal Energy Storage (TES) material that takes advantage of a miscibility gap between two elements or compounds, often metals or semi-metals. MGA encapsulate a distributed fusible phase for latent heat storage inside a matrix phase. Their storage capacity is dominated by the included phase but their high thermal conductivity is...
Below TN = 3.0 K, the bi-layered Fe4Si2Sn7O16 possesses a frustrated Kagome lattice of Fe sites within its FeO6/SnO6 oxide layer1. This magnetic structure contains canted AFM chains whose sites are AFM w.r.t. neighbouring chain sites along y and xy (bridged by NM Sn and frustrated Fe sites) and along z (~9 Å apart and through a non-magnetic FeSn6 cluster layer).
DFT calculations of the...
The lithium containing garnet oxides of Li7La3M2O12 (M = Ta, Nb) were reported to have Li+ conducting abilities back in 2003.1 Since then lithium containing garnet oxides have been identified as a electrolyte candidate for lithium ion batteries as they exhibit the physical and chemical properties desired for a solid-state electrolytes.2 The most notable garnet oxide material is the cubic phase...
This poster highlights some recent upgrades to the Kowari instrument. These include: A wireless cable free remote control for the sample stage allowing freer movement of the operator around the stage when positioning samples; A group of lasers for aligning the primary and secondary/radial collimators as well as allowing accurate positioning of the sample with respect to the primary neutron...
A number of different calibration samples are used on the Beryllium Filter Spectrometer on TAIPAN. Normal-octane is used extensively as a calibration sample because of its well known vibrational modes that are clearly and quite regularly spaced apart over the entire energy range that is covered.
On the other hand alkane chemistry presents itself as an interesting solid-state physics problem....
Vibrational spectroscopy using neutrons as a probe, as opposed to electromagnetic radiation, is a relatively new capability in Australia. A number of instruments at the Australian Centre for Neutron Scattering are capable of measuring vibrational density of states. In particular, the so-called Beryllium Filter Spectrometer, BeF, located on TAIPAN, is devoted to the measurement of vibrational...
We have investigated the background scattering from numerous, frequently used sample adhesives to determine the background contribution of these glues when used for inelastic-neutron-scattering measurements. Starting with a bare Cu sheet, we have trialled different glues such as GE-varnish, Teflon tape, Fomblin oil and two-component epoxy glue. Measurements were collected using the...
Wombat is a high intensity neutron diffractometer located in the OPAL Neutron Guide Hall. It is primarily used as a high-speed powder diffractometer, but has also expanded into texture characterisation and single-crystal measurement, particularly diffuse scattering. The high performance comes from the combination of the best area detector ever constructed for neutron diffraction with the...