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In this study, we report the results of continuous rotation electron diffraction studies of single DyPO4·nH2O (rhabdophane) nanocrystals. The diffraction patterns can be fit to a trigonal lattice (P3121) with lattice parameters a = 7.019 (5) and c = 6.417 (5) Å. However, there is also a set of diffuse background scattering features present that are associated with a disordered superstructure that is double these lattice parameters and fits with an arrangement of water molecules present in the structure pore. Pair distribution function (PDF) maps based on the diffuse background allowed the extent of the water correlation to be estimated, with 2–3 nm correlation along the c axis and ∼5 nm along the a/b axis. [ABSTRACT FROM AUTHOR]

Herein we report for the first time the synthesis of a high entropy (CuZnCoInGa)S metal sulfide thin film deposited by AACVD using molecular precursors. [ABSTRACT FROM AUTHOR]

High-frequency hysteresis measurements were performed on two different types of hydrosois of iron oxide particles: fully dispersed and highly clustered. The fully dispersed sol showed superparamagnetic behavior across the frequency range investigated, while the clustered sample exhibited significant hysteresis. The hysteretic losses were then directly related to magnetic hyperthermia measurements in a sinusoidal field of amplitude 10 mT at 140 kHz, where the clustered sample heated by up to 25[degrees]C in 1000 s while the dispersed sample at similar concentration showed no measurable heating. Index Terms--Frequency response, hysteresis, magnetic particles.

Silica–silver core-shell nanoparticles were produced using colloidal chemistry methods. Surface plasmon resonances in the silver shells were investigated using optical absorption measurements in ultraviolet-to-visible (UV-vis) spectroscopy and the effect of shell thickness on the wavelength of the resonance was noted. Further studies of the resonances were performed using electron-energy-loss spectroscopy (EELS) and energy-filtered transmission electron microscope (EFTEM) imaging. The plasmon resonance was seen in an EELS spectrum at an energy corresponding to the wavelengths measured in an UV-vis spectrophotometer, and EFTEM images confirmed that the resonance was indeed localized at the surface of the silver shell. Further features were seen in the EELS spectrum and confirmed as bulk-plasmon features of silica and the carbon support film in the TEM specimen. [ABSTRACT FROM AUTHOR]

In this study, we report the results of continuous rotation electron diffraction studies of single DyPO 4 ·nH 2 O (rhabdophane) nanocrystals. The diffraction patterns can be fit to a trigonal lattice (P3 1 21) with lattice parameters a = 7.019 (5) and c = 6.417 (5) Å. However, there is also a set of diffuse background scattering features present that are associated with a disordered superstructure that is double these lattice parameters and fits with an arrangement of water molecules present in the structure pore. Pair distribution function (PDF) maps based on the diffuse background allowed the extent of the water correlation to be estimated, with 2-3 nm correlation along the c axis and ∼5 nm along the a/b axis., (open access.)

We report the modulation of reactivity of nitrogen dioxide (NO 2 ) in a charged metal-organic framework (MOF) material, MFM-305-CH 3 in which unbound N-centres are methylated and the cationic charge counter-balanced by Cl - ions in the pores. Uptake of NO 2 into MFM-305-CH 3 leads to reaction between NO 2 and Cl - to give nitrosyl chloride (NOCl) and NO 3 - anions. A high dynamic uptake of 6.58 mmol g -1 at 298 K is observed for MFM-305-CH 3 as measured using a flow of 500 ppm NO 2 in He. In contrast, the analogous neutral material, MFM-305, shows a much lower uptake of 2.38 mmol g -1 . The binding domains and reactivity of adsorbed NO 2 molecules within MFM-305-CH 3 and MFM-305 have been probed using in situ synchrotron X-ray diffraction, inelastic neutron scattering and by electron paramagnetic resonance, high-field solid-state nuclear magnetic resonance and UV/Vis spectroscopies. The design of charged porous sorbents provides a new platform to control the reactivity of corrosive air pollutants., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Nanostructuring is recognized as an efficient route for enhancing thermoelectric response. Here, we report a new synthesis strategy for nanostructuring oxide ceramics and demonstrate its effectiveness on an important n-type thermoelectric SrTiO 3 . Ceramics of Sr 0.9 La 0.1 TiO 3 with additions of B 2 O 3 were synthesized by the mixed oxide route. Samples were sintered in air followed by annealing in a reducing atmosphere. Crystallographic data from X-ray and electron diffraction showed Pm 3̅ m cubic symmetry for all the samples. High-resolution transmission electron microscopy (HRTEM) showed the formation of a core-shell type structure within the grains for the annealed ceramics. The cores contain nanosize features comprising pairs of nanosize voids and particles; the feature sizes depend on annealing time. Atomic-resolution, high-angle annular-dark-field imaging and electron energy loss spectroscopy in the scanning transmission electron microscopy (STEM-HAADF-EELS) showed the particles to be rich in Ti and the areas around the voids to contain high concentrations of Ti 3+ . Additionally, dislocations were observed, with significantly higher densities in the shell areas. The observed dislocations are combined (100) and (110) edge dislocations. The major impact of the core-shell type microstructures, with nanosize inclusions, is the reduction of the thermal conductivity. Sr 0.9 La 0.1 TiO 3 ceramics containing grain boundary shells of size ≈ 1 μm and inclusions in the core of 60-80 nm exhibit a peak power factor of 1600 μW/m·K 2 at 540 K; at 1000 K, they exhibit a low thermal conductivity (2.75 W/m·K) and a power factor of 1050 μW/m·K 2 leading to a high of ZT of 0.39 ± 0.03. This is the highest ZT reported so far for Sr 0.9 La 0.1 TiO 3 based-compositions. This nanostructuring strategy should be readily applicable to other functional oxides.

A new metric is proposed to improve the fidelity of structures refined against precession electron diffraction data. The inherent dynamical nature of electron diffraction ensures that direct refinement of recorded intensities against structure-factor amplitudes can be prone to systematic errors. Here it is shown that the relative intensity of precessed reflections, their rank, can be used as an alternative metric for refinement. Experimental data from erbium pyrogermanate show that applying precession reduces the dynamical transfer of intensity between reflections and hence stabilizes their rank, enabling accurate and reliable structural refinements. This approach is then applied successfully to an unknown structure of an oxygen-deficient bismuth manganite resulting in a refined structural model that is similar to a calcium analogue., (© 2012 International Union of Crystallography)