Abstract: Silver compounds share a rich history in technical applications including photography, catalysis, photocatalysis, cloud seeding and as antimicrobial agents. Here we present a class of silver compounds (Ag2B10H10 and Ag2B12H12) that are semiconductors with a bandgap at 2.3 eV in the green visible light spectrum. The silver boranes have extremely high ion conductivity and dynamic-anion facilitated Ag+migration is suggested based on the structural model. The ion conductivity is enhanced more than two orders of magnitude at room temperature (up to 3.2 mS cm−1) by substitution with AgI to form new compounds. Furthermore, the closo-boranes show extremely fast silver nano-filament growth when excited by electrons during transmission electron microscope investigations. Ag nano-filaments can also be reabsorbed back into Ag2B12H12. These interesting properties demonstrate the multifunctionality of silver closo-boranes and open up avenues in a wide range of fields including photocatalysis, solid state ionics and nano-wire production.

Abstract: The work reports the preparation of diatomite-supported manganese catalysts by deposition-precipitation method, and their application for toluene oxidation. Microstructure and morphology of catalysts were investigated by Powder X-ray diffraction pattern (PXRD), thermogravimetric (TG), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen (N2) adsorption-desorption isotherms. Temperature-programmed reduction (TPR) and temperature-programmed surface reaction (TPSR) were used to analyze the reducibility of Mn species and the reactivity of surface oxygen species, respectively. The characterization results reveal that the manganese species were mainly in the phase of amorphous MnO2 and Mn2O3 on the diatomite, and the manganese species were successfully loaded on diatomite surface and filled in pores. With the increase of Mn content, the catalytic activity enhanced, due to the increase of surface oxygen species as adsorption-reaction sites. The Mn⁴⁺ played an important role in the superior catalytic activity towards toluene. The catalyst also displays high stability and superior activity towards toluene oxidation, which presents an applied interest. The effect of Mn content on the catalytic activity of catalysts was discussed in view of reaction mechanism and variations of physicochemistry properties.

Abstract: Wurtzite Zinc-gallium oxynitrides (ZnGaNO) particles were synthesized by nitridation of Zn/Ga/CO3 layered double hydroxides (LDHs) using three different coprecipitation methods, called Decreasing-pH method, Constant-pH method, and Increasing-pH Method, respectively. The obtained particles were found to be a ZnO/ZnGaNO composite, a single-phase ZnGaNO, and a porous ZnGaNO/ZnGa2O4 composite, respectively, as characterized by X-ray diffraction, scanning electron microscope, scanning and transmission electron microscope, Raman Spectroscopy, UV–vis diffuse refection spectra, and room temperature photoluminescence (PL). Photocatalytic activities of the obtained particles were evaluated under visible-light irradiation against the photodegradation of methylene blue (MB) and phenol. The ZnO/ZnGaNO heterostructure, which was formed due to sequential precipitation of Zn and Ga ions in the Decreasing-pH method, exhibited significant advance in the photocatalytic activity compared to other ZnGaNO particles. The enhanced photoactivity of ZnO/ZnGaNO particles was attributed to efficient separation of photogenerated electron-hole pairs driven by the matched band edges. The predominant active species for the phenol photodegradation over the ZnO/ZnGaNO particles were determined to be superoxide radicals and holes. The facile synthesis of the ZnO/ZnGaNO heterostructure makes it as a potential efficient visible-light responsive photocatalyst for water pollutant degradation.

Abstract: Thin film resistive switching devices based on perovskite SrTiO3 (STO) are the subject of recent studies focused on defect kinetics [1] and electrochemical switching mechanisms [2]—work which has addressed critical aspects of material performance and device design [3]. However, nano- and atomic-scale understanding of switching mechanisms, and the role of device fabrication parameters on switching behavior and device performance is an ongoing area of research [2]. Further, multi-bit architectures offer higher device density, so guidelines for design, fabrication and characterization of these devices is desired. We investigate nano- and atomic-scale aspects of single- and stacked multi-bit thin film resistive switching devices with varying electrode materials and thin film stacking schemes. From a materials perspective, we focus on oxide microstructure, potential highly defective zones, and their interfaces with the different electrodes employed.

Abstract: A key challenge in wire-shaped energy storage devices is their complete encapsulation for practical applications.Hence it is of great importance to design and fabricate an all-inclusive structure in which inner and outercurrent collectors, active materials, electrolyte and separator are all enclosed in a single wire structure.However, due to the surface area differences between the shell and core electrodes, the matching of thecapacitance on both electrodes become a challenging task. We solved this problem by using multiple thin Niwires with three-dimensional MnO2-carbon nanotubes (CNTs)-graphene hybrids as the core electrode and a Nitube as the shell electrode in a coaxial-cable supercapacitors structure. Within the seamless tubular electrode,all the necessary components are included and protected by the metal tube shell. The fully encapsulated singlewire devices show a high area-normalized capacitance of 31 mF cm−2 at a current density of 0.29 mA cm−2,comparable to the best cable devices with more exposed structures. Such devices are more suitable forapplications by providing more mechanical stability and avoiding exposure and loss of electrolytes duringoperation.

Abstract: iAl/Ti2AlC composites were successfully synthesized by vacuum arc melting with TiC, graphite powder, and carbon nanotubes (CNTs) as carbon sources. As the amount of Ti2AlC ceramic increased, the microhardness and compressive strength of the TiAl/Ti2AlC composites improved linearly. Importantly, the TiAl/Ti2AlC prepared with TiC as the carbon source exhibited higher microhardness and compressive strength than that composites prepared with graphite powder or CNTs. During vacuum arc melting, three reactions occur successively: Ti+Al→TiAl, Ti+C→TiC, and TiAl+TiC→Ti2AlC. Ti2AlC was formed by peritectic reaction between the TiAl melt and TiC particles. A large amount of TiC was left in the TiAl matrix, which acted to improve the hardness and strength of the composites. The fracture behavior of the composite was mainly transgranular fracture. The pinning, pulling out, and the effect of crack deflecting of TiC particles, together with the interlayer tearing, plastic shearing, folding, and crimping of Ti2AlC played a key role in the improvement of the strength and plasticity of the composites.

Abstract: A simple method for introducing ZrB2 using sol-gel processing into a SiBCN matrix is presented in this paper. Zirconium n-propoxide (ZNP), boric acid and furfuryl alcohol (C5H6O2) (FA) were added as the precursors of zirconia, boron oxide and carbon forming ZrB2 dispersed in a SiBCN matrix. SiBCN/ZrB2 composites with different contents of ZrB2 (5, 10, 15, and 20 wt%) were formed at 2000 °C for 5 min by spark plasma sintering (SPS). The microstructures were carefully studied. TEM analysis showed that the as formed ZrB2 grains were typically 100–500 nm in size and had uniform distribution. HRTEM revealed clean grain boundaries between ZrB2 and SiC, however, a separation of C near the SiC boundary was observed. The flexural strength, fracture toughness, Young's modulus and Vicker's hardness of composites all improved with the ZrB2 contents and SiBCN matrix containing 20 wt% of ZrB2 could reach 351±18 MPa, 4.5±0.2 MPa·m1/2, 172±8 GPa and 7.2±0.2 GPa, respectively. The improvement in fracture toughness can be attributed to the tortuous crack paths due to the presence of reinforcing particles.

Abstract: The chemical-diffusion and surface-exchange coefficients of a proton-conducting oxide, i.e., Ba(Zr0.84Y0.15Cu0.01)O3−δ upon a sudden change of water-vapor pressure at a fixed oxygen partial pressure are investigated via a conductivity relaxation technique. Conductivity relaxation during the hydration/dehydration process follows typical two-fold non-monotonic behavior that can be explained by decoupled chemical diffusion of H and O. However, the temperature dependence of the measured chemical-diffusion and surface-exchange coefficients is significantly different depending on the direction of the temperature change. In this study, we attempt to identify the origin of these unusual behaviors during the conductivity relaxation experiment via thorough microstructural and compositional analyses on sample surface.

Abstract: Abstract Novel Nextel™ 440 aluminosilicate fiber reinforced SiC matrix composites, with/without chemical vapor deposited carbon interphase were fabricated by polymer derived ceramic process, and they were studied by a combination of micro- and macro- mechanical techniques such as nanoindentation, micropillar splitting, fiber push-in, digital image correction and high temperature three point bend tests. Specifically, micropillar splitting test was firstly employed to measure in-situ the localized fracture toughness. The results revealed that the carbon interphase can effectively hinder the interfacial reactions between Nextel™ 440 fiber and SiC matrix, thus remarkably weakening the composite interfacial shear strength from ∼293 MPa to ∼42 MPa, and enhance the composite fracture toughness from ∼1.8 MPa√m to ∼6.3 MPa√m, respectively. This is mainly a consequence of weak interface that triggers crack deflection at the fiber/interphase interface. Finally, this novel composite showed stable mechanical properties in vacuum at temperature range from 25 °C to 1000 °C.

Abstract: The microstructural stability of YeTieO nanoparticles during spot laser beam melting of oxidedispersion-strengthened steel powder is investigated. After the spot laser beam melting, Y2Ti2O7 oxidenanoparticles are successfully retained without dissolution or transformation. However, their particlesize is considerably coarser than typical Y2Ti2O7 nanoparticles due to the active agglomeration of the YeTieO nanoparticles, Cr-carbides, and Ar bubbles. In particular, an unexpectedly large volume of Arbubbles embedded or attached to the Y2Ti2O7 nanoparticles is observed. The Ar gas bubbles seem toaccelerate the particle agglomeration. No other phase is observed than Y2Ti2O7 oxide, Cr-carbide and Arbubble in the sample.

Abstract: A series of nanoindentation tests on both single and polycrystalline specimens of a monazite rare-earth orthophosphate, GdPO4, revealed frequent observation of anomalous unloading behavior with a large degree of recovery, where previously this behavior had only been observed in xenotime-structure rare-earth orthophosphates. An indentation site in the polycrystalline sample was examined using TEM to identify the deformation mechanism responsible for recovery. The presence of a twin along the (100) orientation, along with a series of stacking faults contained within the deformation site, provide evidence that the mechanism of recovery in GdPO4 is the collapse of deformation twins during unloading.

Abstract: Hyper doping Si with up to 6 at.% Ti in solid solution was performed by ion implantation followed by pulsed laser annealing and flash lamp annealing. In both cases, the implanted Si layer can be well recrystallized by liquid phase epitaxy and solid phase epitaxy, respectively. Cross-sectional transmission electron microscopy of Ti-implanted Si after liquid phase epitaxy shows the so-called growth interface breakdown or cellular breakdown owing to the occurrence of constitutional supercooling in the melt. The appearance of cellular breakdown prevents further recrystallization. However, the out-diffusion and cellular breakdown can be effectively suppressed by solid phase epitaxy during flash lamp annealing due to the high velocity of amorphous-crystalline interface and the low diffusion velocity for Ti in the solid phase.

Abstract: Oriented precipitation of Ti3Al in Ti\\Al alloys has been already proposed, however the underlying physicalmechanism behind the specific precipitation behavior is still unclear. Here, we report that the origin is preferredformation of stacking faults on prismatic planes. In other words, stacking faults induced by Al alloying act as nu-cleation sources for the precipitation of Ti3Al phases, and their particularly spatial distributions assist in“orienting” Ti3Al precipitates (oriented precipitation). These findings enrich current understanding of nanoscaleprecipitation behavior, and provide the inspiration ofcontrolling theprecipitation behaviorbytailoringthephys-ical type and spatial distribution of defects.

Abstract: The effect of oxygen and nitrogen content on the microstructure and mechanical behavior of vanadium was investigated. Vanadium specimens containing 40-4536 ppm nitrogen and 624-9092 ppm oxygen, respectively were prepared using diffusion heat treatments. The specimens were characterized with respect to chemical composition, microstructure and mechanical properties. Both V-O specimens and V-N specimens had single phase microstructure with no precipitates. Increase in oxygen and nitrogen content increased hardness and tensile strength and decreased ductility. The specimens were characterized for grain boundary segregation using scanning transmission electron microscopy (STEM) equipped with super-X EDS and high resolution ion microprobe (NanoSIMS). The mechanical properties were discussed in view of the measurements of composition and microstructure.

Abstract: High-performance and cost-effective electrocatalysts are essential for both oxygen evolution reaction(OER) and oxygen reduction reaction (ORR). Herein, we provide the first report about a facile colloidalmethod to fabricate 2D ultrathin ternary FeNiS2 nanosheets (NSs). When serving as an OER catalystunder alkaline conditions, they exhibited superior electrocatalytic performance over RuO2 and achieved acurrent density of 10 mA cmÀ2 with a potential of 1.54 V and a Tafel slope of 46 mV decadeÀ1. Mean-while, an ORR catalytic activity was also achieved with an onset potential of 0.78 V, a Tafel slope of107 mV decadeÀ1, and a high selectivity with electron transfer number of 3.92 and H2O2% of 3.6% at 0.3 Vunder neutral conditions, which were comparable to those of the commercial Pt/C. The ternary FeNiS2-NSs were superior over the binary FeS NSs and Ni9S8 nanorods synthesized via the same routes. Moreimportantly, with the resistance for the corrosion and poison from the alkaline and phosphate buffersolution, the FeNiS2 NSs exhibited superior stability without apparent OER or ORR catalytic activity lossover long-term operation. Their enhanced electrocatalytic performance compared to their binarycounterparts indicate that a new strategy to prepare high performance OER and ORR catalysts was de-veloped. In addition, the as-prepared FeNiS2 NSs could serve as a noble-metal-free catalyst for OER orORR with good electrocatalytic activities and long-term stability for practical applications.

Abstract: A methodology for the creation of 304LSS-CNT metal matrix composites using the mechanical alloying approach is presented. Planetary ball milled powders were both melted and hot pressed and achieved up to 96% theoretical density. High resolution scanning electron microscopy, Scanning Transmission Electron Microscopy, X-ray diffraction, energy dispersive spectroscopy, thermal diffusivity measurements, and Vickers microhardness measurements are used to characterize as processed and heat treated composites. Melted and solidified samples show highly anisotropic austenite/martensite microstructures with the presence of large dendritic carbon agglomerations, while hot-pressed samples show equiaxed austenite/martensite grains with a large number density of carbide precipitates. Grain size and thermal diffusivity decrease while microhardness increases up to 36% with up to 2% carbon nanotube addition for hot-pressed samples. Thus, mechanical alloying has been shown to be a potential option for the production of homogeneous 304LSS-CNT metal matrix composites for applications requiring increased strength.

Abstract: Oriented precipitation of Ti3Al in Ti-Al alloys has been already proposed, however the underlying physical mechanism behind the specific precipitation behavior is still unclear. Here, we report that the origin is preferred formation of stacking faults on prismatic planes. In other words, stacking faults induced by Al alloying act as nu-cleation sources for the precipitation of Ti3Al phases, and their particularly spatial distributions assist in "orienting" Ti3Al precipitates (oriented precipitation). These findings enrich current understanding of nanoscale precipitation behavior, and provide the inspiration of controlling the precipitation behavior by tailoring the physical type and spatial distribution of defects.

Abstract: In situ Cu-TiB2 composites can be synthesized via metallurgical process by mixing Cu-B and Cu-Ti masteralloys before casting. In this paper, La, as a rare earth element was added to the composites to improvethe comprehensive properties and the effects of its addition on the microstructures, mechanical andelectrical characteristics of Cu-TiB2 composites were investigated. Results show that addition of Lasignificantly diminishes the average size and facilitates a homogeneous distribution of TiB2 particles inthe copper matrix. As a result, an improvement in mechanical properties was achieved. In particular, aremarkable change in the conductivity of the composites appears with the variation of La content. Themechanisms of particle refinement and improvements in properties by La alloying were analyzed.

Abstract: The conductive nanomaterials applicable to unconventional printing techniques have attracted a great deal of attention, and in particular, cost-effective copper-based electrode materials have been recognized as viable candidates for replacement of the expensive silver counterpart. In this study, we synthesize newly designed Cu/Cu10Sn3 core/shell nanoparticles, as an additive material for overcoming the critical drawbacks in Cu nanoparticle-based electrodes, in combination with a large-area processable, continuous photonic sintering process on a time scale of 10–3 s. By virtue of the low-melting point nature of the Cu10Sn3 phase, the facile electrode fabrication process is easily triggered, yielding resistivities of 27.8 and 12.2 μΩ cm under energy dose conditions of 0.97 and 1.1 J/cm2, respectively, at which highly conductive electrodes cannot be obtained from phase-pure Cu nanoparticles. The suspension mixture of Cu and Cu/Cu10Sn3 nanoparticles permits roll-to-roll processable, highly uniform Cu-based electrodes (with a sheet resistance and a standard deviation of 1.21 and 0.29 Ω/square, respectively) even on vulnerable polyethylene naphthalate substrate, while the electrodes derived from Cu10Sn3 phase-free Cu nanoparticles suffer from nonuniform characteristics and even a partially insulating nature. The practical applicability of Cu/Cu10Sn3 core/shell nanoparticles is demonstrated with the fabrication of a touch screen panel and an antenna for wireless power transmission.

Abstract: Herein, we report a bottom-up solvothermal route to synthesize a flexible, highly efficient MoS2@SWNT electrocatalyst for hydrogen evolution reactions (HER). Characterization revealed that branch-like MoS2 nanosheets containing sulfurrich sites were in situ uniformly dispersed on free-standing single-walled carbon nanotube (SWNT) film, which could expose more unsaturated sulfur atoms, allowing excellent electrical contact with active sites. The flexible catalyst exhibited excellent HER performance with a low overpotential (~150 mV at 10 mA/cm2) and small Tafel slope (41 mV/dec). To further explain the improved performance, the local electronic structure was investigated by X-ray absorption near-edge structure (XANES) analysis, proving the presence of unsaturated sulfur atoms and strong electronic coupling between MoS2 and SWNT. This study provides an in-situ synthetic route to create new multifunctional flexible hybridized catalysts and useful insights into the relationships among the catalyst microstructure, electronic structure, and properties.

Abstract: The electrochemical behavior and surface films of pure magnesium and Mg–xSn (x = 2, 5 wt%) alloys were characterized in detail in an NaCl solution for a better understanding of the role of Sn in the corrosion process and film formation. The cathodic hydrogen evolution rate decreased and the protectiveness of surface film increased with the increase of Sn content. All of the films were nanocrystalline and had a double-layered structure, which mainly consisted of Mg(OH)2 and MgO. The porous outer layer of the film became more compact after the addition of Sn. The laminar inner layer in the Mg–Sn alloys was enriched in metallic Sn, because of the preferential dissolution of Mg atoms and the outward growth of the film. Owing to higher Sn content in the film of the Mg–5Sn alloy compared to the Mg–2Sn alloy, the Sn-rich layer could lead to a lower cathodic hydrogen evolution rate because of the higher hydrogen-evolution overvoltage of Sn than Mg. The decreased hydrogen evolution was beneficial to the deposition of Mg(OH)2, which contributed to the increased compactness and corrosion resistance of the surface film.

Abstract: We report herein on the development of Ni-based catalyst using activated carbon fibres (ACFs) as a structured support and its application for the three‐phase hydrogenation of nitroarenes (T = 353 K; P = 10 bar). It was shown that metallic Ni0 nanoparticles (NPs) with a mean diameter of ∼2.0 nm stabilized by the ACF microporous network were responsible for the catalytic transformation. To obtain optimum catalytic activity, the Ni/ACF catalyst must be freshly prepared and activated in situ by H2 at T > 353 K. Pre-treatment of the ACFs by nitric acid boosted the activity of the Ni/ACF catalyst, which exhibits high performance in hydrogenation of nitrobenzene to aniline (yield, Y ∼100%). The catalyst was tested for the reuse attaining a quasi-steady-state after the sixth reaction thereafter remaining relatively stable over seven consecutive runs. Near-quantitative transformation (Y > 99%) of p-chloronitrobenzene to p‐chloroaniline was achieved under mild conditions over the Ni/ACF catalyst with a ca. 20-fold higher activity than conventional Raney Ni. Thus, new catalyst reported here represents a significant step forward towards a simple, heterogeneous catalytic selective hydrogenation of nitroarenes that employs H2 as the hydrogen source.

Abstract: The effect of high-frequency (HF) electric fields on the crystallization and sintering rates of a lithium aluminum germanium phosphate (LAGP) ion conducting ceramic was investigated. LAGP with the nominal composition Li1.5Al0.5Ge1.5(PO4)3 was crystallized and sintered, both conventionally and under effect of electrical field. Electrical field application, of 300 V/cm at 1 MHz, produced up to a 40% improvement in sintering rate of LAGP that was crystallized and sintered under the HF field. Heat sink effect of the electrodes appears to arrest thermal runaway and subsequent flash behavior. Sintered pellets were characterized using X-ray diffraction, scanning electron microscope, TEM, and electrochemical impedance spectroscopy to compare conventionally and field-sintered processes. The as-sintered structure appears largely unaffected by the field as the sintering curves tend to converge beyond initial stages of sintering. Differences in densities and microstructure after 1 h of sintering were minor with measured sintering strains of 31 vs. 26% with and without field, respectively. Ionic conductivity of the sintered pellets was evaluated, and no deterioration due to the use of HF field was noted, though capacitance of grain boundaries due to secondary phases was significantly increased.

Abstract: Copper indium gallium selenide (CIGS) absorber thin films were deposited on bilayer Mo back contacts with and without a SiOx film on a soda-lime glass substrate. This was done to control the quantity of alkali metals in the films and to apply the growth method to a substrate that does not contain alkaline elements. The average concentrations of major elements Cu, In, Ga, and Se in the CIGS solar cells were measured by electron probe microanalysis, secondary ion mass spectrometry (SIMS), and Auger electron spectrometry. The SIMS technique was also used to obtain and compare depth profiles of the relative ion intensities of sodium and potassium alkali metals for CIGS thin films with varying cell efficiencies. The CIGS/Mo interfaces also were investigated by transmission electron microscopy (TEM), whereby a cross-sectional view of Mofilms prepared with and without an initial SiOx layer made possible the detection of a MoSe2/Mo bilayer with a columnar-type microstructure. Scanning TEM images and corresponding elemental maps via energy-dispersive x-ray spectra and high-resolution TEM images revealed the clear formation and orientation of a MoSe2 layer between the CIGS and Mo layers. The solar cell sample exhibiting high efficiency had a thick well-oriented MoSe2 layer at the CIGS/Mo interface, in contrast to the cell sample exhibiting low efficiency.

Abstract: Electron-beam-induced deposition of titanium oxide nanopatterns is described. The precursor is titanium tetra-isopropoxide, delivered to the deposition point through a needle and mixed with oxygen at the same point via a flow through a separate needle. The depositions are free of residual carbon and have an EDX determined stoichiometry of TiO2.2. High resolution transmission electron microscopy and Raman spectroscopy studies reveal an amorphous structure of the fabricated titanium oxide. Ellipsometric characterization of the deposited material reveals a refractive index of 2.2−2.4 RIU in the spectral range of 500−1700 nm and a very low extinction coefficient (lower than 10−6 in the range of 400−1700 nm), which is consistent with high quality titanium oxide. The electrical resistivity of the titanium oxide patterned with this new process is in the range of 10-40 GΩ cm and the measured breakdown field is in the range of 10-70 V  μ m−1. The fabricated nanopatterns are important for a variety of applications, including field-effect transistors, memory devices, MEMS, waveguide structures, bio- and chemical sensors.

Abstract: During the electron beam melting (EBM) process, builds occur at temperatures in excess of 800°C for nickel-base superalloys such as Inconel 718. When coupled with the temporal differences between the start and end of a build, a top-to-bottom microstructure gradient forms. Characterized in this study is a microstructure gradient and associated tensile property gradient common to all EBM Inconel 718 builds, the extent of which is dependent on build geometry and the specifics of a build’s processing history. From the characteristic microstructure elements observed in EBM Inconel 718 material, the microstructure gradient can be classified into three distinct regions. Region 1 (top of a build) is comprised of a cored dendritic structure that includes carbides and Laves phase within the interdendritic regions. Region 2 is an intermediate transition zone characterized by a diffuse dendritic structure, dissolution of the Laves phase, and precipitation of δδ needle networks within the interdendritic regions. The bulk structure (Region 3) is comprised of a columnar grain structure lacking dendritic characteristics with δδ networks having precipitated within the grain interiors. Mechanically, at both 20°C and 650°C, the yield strength, ultimate tensile strength, and elongation at failure exhibit the general trend of increasing with increasing build height.

Abstract: CdS is a very good visible-light responsive photocatalyst for hydrogen production. However, the fast recombination of photogenerated electron-hole pairs and quick photocorrosion limit its application in photocatalysis. To address these problems, we herein have designed and synthesized monodis-perse polyaniline@cadmium sulfide (PANI@CdS) core-shell nanospheres to probe the mechanisms of photocorrosion inhibition and photocatalytic H2 production. All the PANI@CdS core-shell nanospheres demonstrate highly enhanced photocorrosion inhibition and photocatalytic hydrogen production com-paring to the pure CdS nanospheres. Particularly, the PANI@CdS core-shell nanospheres with the thinnest PANI shell possess the highest hydrogen production rate of 310 ␮mol h−1 g−1 in 30 h without deactivation. Our results reveal that the newly formed C S and/or N Cd bonds in PANI@CdS prevent the reduction of the surface sulfide ions to sulphur, leading to effective photocorrosion inhibition. Our results also verify that the photogenerated holes migrating from valence band (VB) of CdS to the highest occupied molecular orbital (HOMO) of PANI leads to the enhanced photocatalytic hydrogen production. This work can shed some light on the mechanism of conducting polymers modifying metal sulfides for effective photocorrosion inhibition and highly enhanced photocatalytic activities.

Abstract: The microstructural stability of Y-Ti-O nanoparticles during spot laser beam melting of oxide dispersion- strengthened steel powder is investigated. After the spot laser beam melting, Y2Ti2O7 oxide nanoparticles are successfully retained without dissolution or transformation. However, their particle size is considerably coarser than typical Y2Ti2O7 nanoparticles due to the active agglomeration of the Y-Ti-O nanoparticles, Cr-carbides, and Ar bubbles. In particular, an unexpectedly large volume of Ar bubbles embedded or attached to the Y2Ti2O7 nanoparticles is observed. The Ar gas bubbles seem to accelerate the particle agglomeration. No other phase is observed than Y2Ti2O7 oxide, Cr-carbide and Ar bubble in the sample.

Abstract: Catalysts that contain two types of active site split long hydrocarbon molecules into more-useful shorter ones Research into controlling the nanoscale separation of the sites challenges accepted design rules for such catalysts.

Abstract: A facile large-scale hydrothermal process was proposed to synthesize core-shell nanobelts with single-crystalline Bi nanobelts as cores that may be resulted from the pseudolayered structure and poly(vinyl alcohol) (PVA) as shells in which PVA chains reduced sodium bismuthate in mixed solution. The results have demonstrated that the formation of such Bi nanobelts is controlled by seed-mediated growth in an Ostwald ripening process, in which Bi nanostructures evolved through repetitive crystalline-amorphous transformations. In addition, STEM-EDS and HRTEM have confirmed that the shells of Bi nanobelts are indeed as same as the transparent amorphous Bi nanobelts composed of amorphous Bi and PVA.

Abstract: A ternary photocatalyst TiO2-Au-CdS based on three-dimensionally ordered macroporous TiO2 (3DOM TiO2) was successfully prepared to enhance the light absorption, extend the light responsive region, reduce the recombination rate of charge carriers and promote the efficiency of water splitting H2 evolution ultimately. The obtained 3DOM TiO2-Au-CdS powder has a pure anatase phase of TiO2 and greenockite structured CdS according to the XRD results and TEM analysis. Au nanoparticles (AuNPs) and CdS were evenly distributed in the 3DOM structure which enhances H2-generation rate under visible light by improving light harvesting and utilizing its mass transfer facilitation. As a result, the hydrogen gen-eration rate (1.81 mmol h−1 g−1) using 3DOM TiO2-Au-CdS photocatalyst under visible light irradiation was 13-fold higher than the binary 3DOM TiO2-CdS reference photocatalyst. Under ultraviolet-visible light, the photogenerated electrons in TiO2 would be transferred to recombine with the holes of CdS and under visible light, electrons would move to the conduction band (CB) of TiO2 from CdS via AuNPs. The two different types of internal electron-transfer process in the ternary photocatalyst under ultraviolet and visible light were proposed respectively and both would efficiently reduce the recombination rate of photogenerated electrons and holes thus stimulate H2 evolution rate. The present work demonstrated an excellent example of the synergistic effect of the light absorption enhancement by 3DOM structure, the photosensitizing and electron reservoir effect of AuNPs and the reduction of recombination rate of charge carriers by CdS to highly promote the photocatalytic activity in water splitting reaction.

Abstract: A thin section sample of gadolinium nanoparticles ranging in size up to 50 nm mounted on an aluminum substrate was prepared using in-situ lift-out (INLO) by FIB. The sample was thinned using 30 kV Ga+ FIB to approximately 125 nm. Using an in-situ stage with 360 degree continuous tilt, the thin section was imaged every 1 degree with 30 keV SEM and the STEM detector through approximately 125 degrees of tilt. The data set was then reconstructed into a 3D rendering using Thermo Scientific tomography reconstruction software, Inspect3D Express, and visualized using our Avizo image and data analysis software. The technique and results compared with conventional TEM and STEM tomography using a 200 keV Thermo Scientific™ Talos TEM will be discussed.

Abstract: Coating nickel onto copper nanowires (Cu NWs) by one-pot synthesis is an efficient approach to improving the oxidation resistance of the nanowires. Because Ni is much less conductive than Cu, it is of great importance to understand the relationship between the thickness of the Ni coating layer and the properties of NWs. Here we demonstrate one-pot synthesis of Cu-Ni core-shell NWs with a tunable Ni thickness by simply varying the Cu and Ni mole ratio in the precursor.

Abstract: Carbon coated LiNi0.5Mn1.5O4/C composite has been directly synthesized at 800 °C without using reducing gas or introducing additional low temperature treatments. Scanning/transmission electron microscope (S/TEM) observation shows clear coating layer on the particle's surface, which has been verified by Energy Dispersive X-Ray Spectroscopy (EDX), Raman spectra and Brunauer-Emmett-Teller (BET); and the results indicate the coating layer is amorphous carbon which significantly increases the BET surface area, and the carbon content is around 0.6 wt%.

Abstract: This study investigates the synthesis of base catalysts through the postsynthetic grafting of alkali cations (Li, Na, K, Rb, or Cs) onto USY zeolites in alcoholic solutions of the corresponding metal hydroxides. In contrast to previous studies conducted in aqueous media, the utilization of alcohols (MeOH, EtOH, or iPrOH) offers increased control over the metalation process while simultaneously averting degradation and dissolution of the crystalline framework. The achievement of close to an atomic dispersion of the alkali metals in the zeolite is confirmed by in-depth characterization combining 23Na MAS NMR, microscopy, elemental mapping, and CO2 chemisorption.

Abstract: A modified sol–gel (MSG) method was developed to synthesize perovskite La1−x Srx MnO3 (x = 0.2, 0.4, 0.6, 0.8) with large specific surface area that allows for control of their particle size from the micrometer level to the nanometer level with novel nanoporous structure. The MSG method utilized carbon black (Vulcan XC-72R) as a pore-forming material during the preparation process. Two important process parameters, the calcination temperature and the pore former material addition, were investigated to control the size of the La1−x Srx MnO3 particles. The phase evolution of La1−x Srx MnO3 powders was investigated by thermogravimetric analysis (TG/DSC) and X-ray diffraction pattern. The results showed that the pure La0.6Sr0.4MnO3 phase has been obtained at about 550 °C in air, which is lowered around 150 °C comparing to conventional sol–gel method. In scanning electron microscope studied, it presented novel homogeneous nanoporous morphology with the average particle size from 30 to 100 nm. Based on the Brunauer–Emmett–Teller method analysis, the specific surface area of La1−x Srx MnO3 was significantly influenced by the calcination temperature, the pore former material addition and the strontium content. The largest specific surface area of La0.2Sr0.8MnO3 reached 114.3 m2/g.

Abstract: Tin-containing nanocrystals, embedded in silicon, have been fabricated by growing an epitaxial layer of Si_{1-x-y} Sn_{x}C_{y}, where x = 1.6 % and y = 0.04 %, followed by annealing at various temperatures ranging from 650 to 900 degrees C. The nanocrystal density and average diameters are determined by scanning transmission-electron microscopy to ~ 10^{17} cm^{-3} and ~ 5 nm, respectively. Photoluminescence spectroscopy demonstrates that the light emission is very pronounced for samples annealed at 725 degrees C, and Rutherford back-scattering spectrometry shows that the nanocrystals are predominantly in the diamond-structured phase at this particular annealing temperature. The origin of the light emission is discussed.

Abstract: Since its discovery, graphene and its oxidized form, graphene oxide (GO), have attracted interest in a wide range of technical applications. Concerns about their potential toxicity calls for scrutinized studies, but hitherto conflicting results have been reported which partly may be due to variations of synthesis and exposure procedures. Here we report on the attachment and toxicity of contamination-free graphene oxide nanoparticles (GONP) in living lung epithelial cells.

Abstract: The synthesis of well-defined and complex hollow structures via a simple method is still a major challenge. In this work, a facile and controllable "multi-interface transformation" approach for preparation of monodisperse multi- shelled periodic mesoporous organosilica (PMO) hollow spheres has been established by a one-step hydrothermal treatment of successively grown organosilica particles. In addition, various organic groups (alkyl, aromatic, nd heteroelement fragments) are successfully incorporated into the multi-shelled PMO hollow spheres by successively adding different bridged organosilica precursors.

Abstract: The integration of III-V compound semiconductors in Si is a crucial step towards faster and smaller devices in future technologies. In this work, we investigate the formation process of III-V compound semiconductor nanocrystals, namely, GaAs, GaSb, and InP, by ion implantation and sub-second flash lamp annealing in a SiO2/Si/SiO2 layer stack on Si grown by plasma-enhanced chemical vapor deposition. Raman spectroscopy, Rutherford Backscattering spectrometry, and transmission electron microscopy were performed to identify the structural and optical properties of these structures.

Abstract: A systematic study was carried out to investigate the response of monodisperse supported Fe and FeMn nanoparticles to treatments in O2, H2 and H2/CO at temperatures between 270 and 400°C. Uniform size (7-14 nm), Fe and mixed FeMn nanoparticles were synthesised by applying thermal decomposition of Fe- and Mn-oleate complexes in a high boiling point solvent. By combining X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) analysis, the phase composition and morphology of the model catalysts were studied.

Abstract: Nanostructured hard coatings are becoming fundamental in many application areas due to their highly enhanced mechanical properties compared to conventional materials. Among others, novel quaternary systems are attracting increasing attention since they are expected to further improve endurance of such coatings. In this work, combined experimental and ab initio analysis of thermal stability and structural evolution of quaternary Ti-Ta-B-N coatings with Ta content 0-40 at.% prepared by reactive magnetron co-sputtering is presented. All prepared Ti1-x-yTaxByN coatings in the as-deposited state exhibit amorphous structure, which is supported by ab initio calculations.