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Ni nanoparticles (NiNPs) were prepared by thermal decomposition of nickel acetylacetonate in the presence of a third generation polypyridylphenylene dendrimer (G3) which acts both as a coordinating ligand due to presence of pyridine groups and as a stabilizing agent due to highly branched architecture. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), and X‐ray photoelectron spectroscopy (XPS) were used to extensively evaluate structure and morphology of the synthesized NiNPs@G3. The selected area electron diffraction (SAED) allowed us to conclude about fcc structure of NiNPs while STEM EDS analysis demonstrated a formation of core‐shell NiO@Ni NPs. Further, the catalyst was tested in selected Suzuki‐Miyaura cross‐coupling reactions at mild conditions and demonstrated a high efficiency at low Ni loading with negligible content of Ni0 on the NP surface. The functional hyperbranched dendrimer macromolecule provided an excellent stabilization for NiNPs@G3 while allowing an easy access for reactants to catalytic sites. The high activity of the catalyst in the recycling experiments was maintained by the absence of Ni leaching from the NiNPs@G3. [ABSTRACT FROM AUTHOR]

Mechanical stirring of bulk Te in N‐methyl‐2‐pyrrolidone (NMP) solution at room temperature resulted in the formation of free‐standing few‐layer (∼1.2–2.8 nm) crystalline ultrathin nanosheets of tellurene with a large lateral thickness (∼1–1.6 μm) as confirmed by atomic force microscopy (AFM). High‐resolution transmission electron microscopy (HRTEM) confirms the presence of α‐ and β‐phases of tellurene. First‐principle density functional theoretical (DFT) based electronic structure calculations demonstrate the indirect band gap of bi‐layer β‐tellurene. The band gap decreases with increasing number of layers in the tellurene nanosheet. [ABSTRACT FROM AUTHOR]

Herein we report a facile approach for the preparation of a magnetically separable Fe3O4@poly(m‐phenylenediamine)@Cu2O nanocatalyst and its catalytic efficiency in the synthesis of 5‐phenyl‐[1,2,3]triazolo[1,5‐c]quinazolines from (E)‐1‐bromo‐2‐(2‐nitrovinyl)benzenes, aldehydes, and sodium azide under mild reaction condition is described. The morphology, chemical composition, interior structure and magnetic properties of the Fe3O4@PmPDs@Cu2O nanocomposites were studied using powder X‐ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray photoelectron microscopy, vibrating sample magnetometer and nitrogen adsorption‐desorption technique. The as‐prepared Fe3O4@PmPDs@Cu2O nanocatalyst was simply recovered using external magnet and reused up to successive six runs with no obvious loss in its catalytic efficiency and structural integrity (confirmed by powder X‐ray diffraction and transmission electron microscopy of recycled nanocatalyst) along with low leaching of copper (2.32 ppm) and iron (0.008 ppm) ions. The present protocol has a broad substrate scope with high yield in shorter reaction time and it does not require any additive or base. Overall, it has better green chemistry metrices like low E‐factor (0.93), process mass intensity (1.93), high reaction mass efficiency (51.9 %) and carbon efficiency (95 %). [ABSTRACT FROM AUTHOR]

Cuboid‐shaped anatase TiO2 nanocrystals with co‐exposed {101} and [111]‐facets (or {101} and {100} facets), diamond‐shaped, rod‐like and irregular anatase TiO2 nanocrystals with dominant {010} facets were controllably synthesized from titanium (IV) ethoxide (TEOT) using HF as a capping agent via a facile sol‐gel procedure, and characterized by X‐ray powderdiffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), nitrogen adsorption, photoluminescence (PL) spectra, UV‐vis diffuse reflectance spectra,and electrochemical impedance spectroscopy (EIS). For the as‐prepared anatase TiO2 nanocrystals, the 0.5HF‐TiO2 revealed the best photocatalytic efficiency under UV light irradiation: 94.1 % of methylene blue (MB) was photodegraded within 90 min. The reaction rate constant k(min−1) was 1.39, 1.47, 1.59, 1.66, 1.92, 2.75, and 30.5 times higher than that of 2.0HF‐TiO2 (2.20×10−2 min−1), 1.5HF‐TiO2 (2.07×10−2 min−1), 1.0HF‐TiO2 (1.92×10−2 min−1), 2.5HF‐TiO2 (1.84×10−2 min−1), 3.0HF‐TiO2 (1.59×10−2 min−1), Bodi‐TiO2 (1.11×10−2 min−1), and the blank sample (0.10×10−2 min−1), respectively. Compared to other as‐prepared anatase TiO2 nanocrystals with the similar co‐exposed crystal facets, the highest efficiency of 0.5HF‐TiO2 could be attributed to the minimum crystal size,narrower pore size distribution, the maximum specific surface area, the lowest PL intensity and charge‐transfer resistance, andthe smallestrecombination resistance. [ABSTRACT FROM AUTHOR]

In a sample with nominal composition BiCr2S5 a new misfit layer compound has been synthesized and studied via transmission electron microscopy (TEM). It presents a composite modulated structure with a composition that can be formulated as (BiS)1.19[(CrS2)‐Bi1/3‐(CrS2)]. It consists of the periodic stacking of a Q layer (BiS) with two H layers (CrS2), ...QHHQHH..., with additional bismuth atoms inserted between the H layers. Selected area electron diffraction (SAED) patterns show an almost commensurate fit between the pseudo‐tetragonal Q (BiS) and the pseudo‐orthohexagonal H (Bi1/3Cr2S4) subcells along the misfit direction a, being b the same for both sublattices and c the layers stacking direction. In addition to the characteristic misfit modulation between the two sub‐structures, a second modulation is observed in the H sub‐structure produced by the ordering of bismuth atoms within the Van der Waals gap that occurs between consecutive H layers. High resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) images show ordered stacking sequences between the (BiS) and (Bi1/3Cr2S4) layers. Besides, disordered intergrowths have been occasionally found as well as different kinds of twinning defects. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (NPs) in a transparent dielectric matrix represent a very intriguing system due to the plasmonic absorption tunable in the range of visible wavelengths. Herein, the preparation and physical characterization of plasmonic titania–silver dots thin films are reported. The synthesis parameter that leads to making a TiO2 matrix in which the Ag NPs are actually incorporated is carefully analyzed and controlled. Morphological (scanning electron microscopy, transmission electron microscopy, high resolution electron microscopy), structural (selected area diffraction, X‐ray diffraction), and spectroscopic (Raman spectroscopy) characterization techniques attest that the Ag NPs are spherical and homogeneously distributed into the TiO2 dielectric matrix in the structural modification of anatase. The study of the optical properties of films concludes the work. Plasmonic resonance is analyzed according to the light scattering theory. [ABSTRACT FROM AUTHOR]

Summary: Geometrical phase analysis (GPA) is typically a powerful tool to investigate the deformation in high resolution transmission electron microscopy images and has been used in various fields. During GPA, strain components are calculated relative to an undistorted reference region. In the present work, the effect of reference region size on strain measurements has been investigated. Experimental measurements on a locally distorted gold nanoparticle exhibited that a small reference region below the GPA spatial resolution can introduce an inaccuracy in the measured displacement field, which appears as a significant increase in measured strains and severe fluctuation in phase images. The inaccuracy may be ascribed to an error of insufficient sampling. Our results suggest that a small reference region below the GPA spatial resolution should be avoided during GPA. This prerequisite should be paid more attention to during strain measurement on nanoparticles. [ABSTRACT FROM AUTHOR]

As a potential remedy for addressing water scarcity challenges, advanced oxidation processes (AOP) present the opportunity of alleviating the water demand in water scarce regions. In this study appropriate doping of N and Pt into the titanium dioxide (TiO2) lattice using different dendrimers as templates and sources of nitrogen was demonstrated. The resulting N, Pt co‐doped TiO2 with small particle sizes was synthesized through a simple modified sol‐gel method. The N, Pt co‐doped TiO2 photocalysts were characterized through High Resolution Scanning Electron Microscopy (HR‐SEM) coupled with Energy Dispersive Spectroscopy (EDS), Transmission Electron Microscopy (TEM), Brunauer‐Emmett‐Teller  (BET), Raman Spectroscopy (RS), X‐ Ray Diffraction (XRD), Fourier‐transform Infrared Spectroscopy (FTIR), Thermo‐gravimetric analysis (TGA), Ultraviolet and visible (UV‐Vis) absorption spectroscopy  (UV‐Vis) and Photoluminescence (PL). The band gap reduction was more pronounced for the Poly (amidoamine) generation 1 (PAMAM G1) templated N, Pt co‐doped TiO2 (Eg=3.149 eV) compared to Poly (amidoamine) generation 0 (PAMAM G0) and Hyperbranched polyethylenimine (HPEI) templated N, Pt co‐doped TiO2. Co‐doping led to an enhancement in the photocatalytic activity of the photocatalysts for the degradation of brilliant black (99.83%) after 3 hours of visible light irradiation. Therefore, the synthesized photocatalysts can find applications in wastewater treatment using solar light. [ABSTRACT FROM AUTHOR]

There were contradictory results about the effect of clay on polycarbonate (PC) thermal stability in previous reported papers. For ascertainment of the actual role of clay, PC nanocomposites were prepared by direct melt-mixing PC with hexadecyl trimethyl ammonium chloride modified montmorillonite (OMT). The results of X-ray diffractometry, transmission electron microscopy, and high-resolution electron microscopy experiments present the formation of uniformly intercalated structure. Thermogravimetric analyses show the onset decomposition temperature of PC/OMT nanocomposites is earlier 65°C than neat PC. The mechanism of PC thermal decomposition effected by OMT was discussed in detail. It reveals that OMT can catalyze thermal degradation of PC macromolecular chains and decrease thermal stability of the nanocomposites. POLYM. COMPOS., 37:2301-2305, 2016. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Fe-Bi nanoparticles were prepared in the gas-phase by DC magnetron sputtering and in-fight annealing. The morphological, structural and compositional properties were investigated by High-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy and scanning transmission electron microscopy. High-resolution microscopy studies show that primary particles produced without in-flight annealing are spherical with a diameter of about 50 nm. Particles sintered at 773 K acquire a dumbbell structure with Fe-FeO and Bi sections. [ABSTRACT FROM AUTHOR]

Cross-sectional transmission electron microscopy and X-ray phase analysis were used to study the structure of a layer formed during nitriding the AISI 316L stainless steel at temperature 440°C. It was found that the applied treatment led to the formation of 6-μm-thick layer of the S-phase. There is no evidence of CrN precipitation. The X-ray diffraction experiments proved that the occurred austenite lattice expansion – due to nitrogen atoms – depended on the crystallographic direction. The cross-sectional transmission electron microscopy studies showed that the layer consisted of a single cubic phase that contained a lot of defects such as dislocations, stacking faults, slip bands and twins. The high-resolution electron microscopy observations were applied to study the defect formation due to the nitriding process. It was shown that the presence of great number of stacking faults leads to formation of nanotwins. Weak, forbidden {100} reflections were still another characteristic feature of the S-phase. These were not detected in the X-ray spectra of the phase. Basing on the high-resolution electron microscopy studies it can be suggested that the short-range ordering of the nitrogen atoms in the octahedral sites inside the f.c.c. matrix lattice takes place and gives rise to appearance of these spots. It is suggested that the cubic lattice undergoes not only expansion but also slight rombohedral distortion that explains differences in the lattice expansion for different crystallographic directions. [ABSTRACT FROM AUTHOR]

Cation ordering and domain boundaries in perovskite Ca[(Mg1/3Ta2/3)1− xTi x]O3 ( x=0.1, 0.2, 0.3) microwave dielectric ceramics were investigated by high-resolution transmission electron microscopy (HRTEM) and Rietveld analysis. The variation of ordering structure with Ti substitution was revealed together with the formation mechanism of ordering domains. When x=0.1, the ceramics were composed of 1:2 and 1:1 ordered domains and a disordered matrix. The 1:2 cation ordering could still exist until x=0.2 but the 1:1 ordering disappeared. Neither 1:2 nor 1:1 cation ordering could exist at x=0.3. The space charge model was used to explain the cation ordering change from 1:2 to 1:1 and then to disorder. A comparison between the space charge model and random layer model was also conducted. HRTEM observations showed an antiphase boundary inclined to the (111) c plane with a projected displacement vector in the 〈001〉 c direction and ferroelastic domain boundaries parallel to the 〈100〉 c direction. [ABSTRACT FROM AUTHOR]

Cover Picture: Direct Synthesis of ZIF-8 on Transmission Electron Microscopy Grids Allows Structure Analysis and 3D Reconstruction (Part. Keywords: chemical composition analysis; electron microscopy; high spatial resolution, layer-by-layer growth; surface-anchored metal-organic frameworks; zeolitic imidazolate framework-8 EN chemical composition analysis electron microscopy high spatial resolution, layer-by-layer growth surface-anchored metal-organic frameworks zeolitic imidazolate framework-8 1 1 1 11/23/20 20201101 NES 201101 In article number 2000209, Milena Hugenschmidt and co-workers report on a ZIF-8 surface-anchored metal-organic framework (SURMOF) synthesized on transmission electron microscopy (TEM) grids, allowing for TEM analysis of samples that are not damaged by further preparation steps. Chemical composition analysis, electron microscopy, high spatial resolution, layer-by-layer growth, surface-anchored metal-organic frameworks, zeolitic imidazolate framework-8. [Extracted from the article]

The structure of Al3Zr precipitates in Al-1.0Mg-0.6Si-0.5Zr (in wt.%) alloy was investigated using conventional transmission electron microscopy (TEM) and high-resolution TEM (HREM). After annealing of the alloy in the temperature range 450–540 °C, spherical precipitates of metastable L12-Al3Zr phase appeared nearly homogeneously within the matrix, and elongated particles were found at grain boundaries. L12-structured Al3Zr were about 20–30 nm in diameter and coherent with the matrix. Inside some of them, planar faults parallel to {100} planes were revealed by use of HREM. Most probably, these faults are an indication of the transition stage of transformation to the stable D023-type Al3Zr phase. The elongated precipitates (about 100 nm) were identified as D022-type Al3Zr. Energy-dispersive X-ray analysis showed that they contain, apart from Al, mainly Zr with small amounts of Si. The substitution of Al by Si increased the stability of the D022-Al3Zr as compared with D023-Al3Zr. [ABSTRACT FROM AUTHOR]

In a boron nitride thin film, grown on a Si (100) substrate by radio frequency magnetron sputtering, a striking nanostructure is observed by high-resolution transmission electron microscopy. It consists of cubic boron nitride nanocrystals with a rather good triangular shape, pointing always to the substrate. The nanocrystals are usually highly defected and present their own interesting internal structure. Texture formation is observed within a nanocrystal, with all the subgrains observed to have a common <011> axis, which is also approximately parallel to a <011> axis of the Si substrate, i.e. the nanocrystals are very well structurally orientated in relation to the Si substrate (self-organized). Dislocations and stacking faults are also found in the nanocrystals. [ABSTRACT FROM AUTHOR]

A Windows-based computer program has been developed for exit-wave reconstruction and experimental high-resolution transmission electron microscopy image alignment. While the exit-wave reconstruction is performed mainly using the maximum-likelihood method, image alignments may be carried out using several algorithms, including the time-consuming but robust genetic algorithm. [ABSTRACT FROM AUTHOR]