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The title compound, {(C2H8NO)2[SnBr4]}n, is a layered hybrid perovskite crystallizing in the monoclinic space group C2/c. The asymmetric unit consists of one H3C--O--NH2 +--CH3 cation (Me2HA+), one SnII atom located on a twofold rotation axis, and two Br atoms. The SnII atom has a distorted octahedral coordination environment formed by the bromido ligands. The {SnBr6} units corner-share their equatorial Br atoms, forming infinite mono-layers that extend parallel to the ab plane. These inorganic layers are sandwiched by the organic Me2HA+ cations organized in double-layers; stacking of the layers is along the c-axis direction. Consecutive inorganic layers, separated by the organic cations, are shifted relative to each other along the b-axis direction. Specifically, the SnII atom in one inorganic layer is offset by 3.148 A ° along the b axis relative to the SnII atom in an adjacent inorganic layer. The N,O-dimethylhydroxylammonium cation forms two hydrogen bonds with the axial bromide anions of the inorganic layers as acceptors, and leads to the cohesion of the crystal structure. According to Hirshfeld surface analysis, the highest contributions to the crystal packing are from H···H (46.2%), Br···H (38.5%), and H···O (14.8%) contacts. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a comprehensive theoretical study to obtain an optimal highly sensitive fluidic sensor based on the one-dimensional phononic crystal (PnC). The mainstay of this study strongly depends on the high impedance mismatching due to the irregularity of the considered quasi-periodic structure, which in turn can provide better performance compared to the periodic PnC designs. In this regard, we performed the detection and monitoring of the different concentrations of lead nitrate (Pb(NO3)2) and identified it as being a dangerous aqueous solution. Here, a defect layer was introduced through the designed structure to be filled with the Pb(NO3)2 solution. Therefore, a resonant mode was formed within the transmittance spectrum of the considered structure, which in turn shifted due to the changes in the concentration of the detected analyte. The numerical findings demonstrate the role of the different sequences such as Fibonacci, Octonacci, Thue–Morse, and double period on the performance of the designed PhC detector. Meanwhile, the findings of this study show that the double-period quasi-periodic sequence provides the best performance with a sensitivity of 502.6 Hz/ppm, a damping rate of 5.9 × 10 − 5 , a maximum quality factor of 8463.5, and a detection limit of 2.45. [ABSTRACT FROM AUTHOR]

Compared to many conventional manufacturing methods, Additive Manufacturing/3D Printing (AM/3DP) techniques can produce highly optimized builds with unparalleled structural complexities, material combinations, and both internal and external geometrical intricacies, offering new degrees of freedom for optimization. However, unforeseen deviations in process parameters (e.g., laser beam scan speeds and power), material properties (e.g., powder morphology, alloy composition, mechanical and thermal properties), and machine health can lead to micro/macro-scale defects and quality concerns in the resulting builds and end-products. To address these concerns, it is crucial to assess quality and implement effective closed-loop control by understanding the sensitivity of quality attributes to perturbations and variations in process parameters, material properties, and machine health state. AM print speeds influence the material's microstructure, affecting its elastic properties, defect states, and, consequently, spectral resonance behavior. Here, a quality monitoring framework is introduced based on specially designed Phononic Crystal Artifacts (PCAs) printed alongside the actual build. Compared to the actual build, a PCA is a substantially smaller construct with a repeating pattern (periodic) internal structure to effectively capture and measure the build's defect state and mechanical and geometric complexities for quality assessment. In this study, we investigate the impact of varying print speeds in AM on the resonance frequencies of PCAs, which are related to mechanical properties and defects. Stainless steel 316L powder, widely used in powder-based AM/3DP, was chosen to print the Metal Phononic Crystal Artifacts (mPCAs). Our findings indicate that varying print speeds significantly influence ultrasonic waves' resonance and modal frequencies in the printed artifacts. Specifically, high print speeds resulted in measurable shifts in these frequencies, demonstrating the potential for real-time quality monitoring and process optimization in AM/3DP. The PCA approach offers real-time, non-destructive quality monitoring by using smaller, sensitive constructs to capture essential mechanical and geometric complexities, allowing for dynamic adjustment of print speeds and enhancing overall build precision and reliability in AM/3DP. [ABSTRACT FROM AUTHOR]

The impact of elastic energy anisotropy on the drag thermopower in noble metals at low temperatures has been investigated. In order to describe the interaction of electrons with longitudinal phonons, the strain potential theory has been employed. In calculating electron relaxation on shear components of vibrational modes, the electron–phonon interaction constant, previously determined from a comparison of the calculated electrical resistivity of Au, Ag, and Cu bulk crystals with experimental data, was used. The maximum values of the drag thermopower in perfect noble metal crystals have been determined. These values are independent of the electron–phonon interaction constants; rather, they are determined by the elastic moduli of the second order, crystal density, and electron concentration. It has been demonstrated that quasi-transverse phonons constitute predominant contribution to the drag thermopower at low temperatures, whereas the contribution of longitudinal phonons were found to be negligible. At the same time, for perfect Au, Ag, and Cu crystals, the dominant contribution to the electron–phonon drag is provided by the slow t2-mode. [ABSTRACT FROM AUTHOR]

Single crystals of refractory metals with a given orientation are demanded in both the power-optics and high-power laser applications. The evolution of liquid-phase methods for growing such refractory metals as the molybdenum and tungsten single crystals is analysed. As shown, the methods for growing crystals with a single heating source cannot solve the problem of fabrication of industrial-sizes' crystals. The superlarge single crystals of various configurations, such as ingot and plates, can be grown using the combined plasmainduction method. The single-crystalline quality of the ingots and the preservation of the orientations of the selected crystallographic axes are confirmed by the x-ray method according to Laue images. The repeatability of physical and mechanical properties is shown by the indentation test. [ABSTRACT FROM AUTHOR]

A complex of [Zn(pza)2(Cl)2], pza = pyrazinamide, was successfully crystallized from methanol or ethanol solvents with different morphology. The complex was synthesized using the solution method in ZnCl2: pza mol ratios of 1:2 and 1:4 in both ethanol and methanol solvents. FTIR and single crystal XRD analyses were done to confirm the complex. The complex was then used for in vitro antibacterial test against E. coli and S. aureus. Experimental data shows that the type of solvent and metal-to-ligand mol ratio yields the same compound, resulting in colorless crystals that melt at 234-236°C. Large block crystals were obtained from the methanolic solution, while a higher yield was obtained from the use of a higher mol ratio of 1:4. Infrared spectra analysis confirms the presence of characteristic carbonyl and amide groups of the pza ligand. Meanwhile, single crystal XRD screening indicates that unit cell parameters of the crystals from both solvents are identical to a known zinc(II)-pza complex. In vitro antibacterial tests against E. coli and S. aureus show that the complex had much better activity than the ZnCl2 and the free pza. In addition, the complex performs better antibacterial activity toward gram-positive S. aureus than the gram-negative E. coli. [ABSTRACT FROM AUTHOR]

As a member of 2D family, amorphous 2D nanosheets have received increasing attention due to their unique properties that are distinct from crystalline 2D nanosheets. However, compared with the vast library of crystalline 2D nanosheets, amorphous 2D nanosheets are still infancy due to the lack of an efficient synthetic approach. Here, we present a strategy that yields a library of 10 distinct amorphous 2D metal oxides/oxyhydroxides using solid-state surfactant crystals. A key feature of this process is a stepwise reaction using solid surfactant; the solid-state surfactant crystals have metal ions arranged in the interlayer space, and hydrolysis of the metal ions leads to the formation of isolated clusters in the surfactant crystals via limited condensation reactions. Immersing the surfactant crystals in formamide promotes nanosheet formation through the self-assembly of clusters by templating the morphologies of the crystals generated from surfactants crystals. Our approach opens a flatland in amorphous 2D world. The authors developed a method for creating amorphous 2D nanosheets using solid-state surfactant crystals. This strategy results in a library of 10 distinct amorphous 2D metal oxides/oxyhydroxides through stepwise hydrolysis and assembly processes. [ABSTRACT FROM AUTHOR]

Zirconium alloy with the composition of 90.1% Zr and alloying elements such as Mg, Al, and Si was investigated for its mechanical properties and corrosion resistance. The specimen was dissolved in a mixture of NaOH, Na2CO3, S, and SnO2 at 800°C for 10 min, followed by an HCl solution at room temperature for 100 cycles. The structural properties were characterized by X-ray diffraction and scanning electron microscopy, while the mechanical properties, such as tensile strength were investigated by a universal tensile machine. The microstructural observations indicated that the outside part of the crucible underwent pitting corrosion which resulted in corrosion in all directions inside that part of the crucible. The corrosion structure consisted of cracks that reached the base metal. The residual chemical from the fusion and dissolution process remained in the crack and formed NaCl, which accelerated the crack. The release rate of the zirconia oxide layer was calculated to be 8 μm per cycle. During the corrosion process at high temperatures, oxygen diffusion infiltrated the base metal and stretched the crystal lattice, causing strain hardening with the values of yield strength and ultimate tensile strength increased to 22.5% while the strain decreased by 50%. [ABSTRACT FROM AUTHOR]

Refractory metal single crystals have been applied in key high-temperature structural components of advanced nuclear reactor power systems, due to their excellent high-temperature properties and outstanding compatibility with nuclear fuels. Although electron beam floating zone melting and plasma arc melting techniques can prepare large-size oriented refractory metals and their alloy single crystals, both have difficulty producing perfect defect-free single crystals because of the high-temperature gradient. The mechanical properties of refractory metal single crystals under different loads all exhibit strong temperature and crystal orientation dependence. Slip and twinning are the two basic deformation mechanisms of refractory metal single crystals, in which low temperatures or high strain rates are more likely to induce twinning. Recrystallization is always induced by the combined action of deformation and annealing, exhibiting a strong crystal orientation dependence. The irradiation hardening and neutron embrittlement appear after exposure to irradiation damage and degrade the material properties, attributed to vacancies, dislocation loops, precipitates, and other irradiation defects, hindering dislocation motion. This paper reviews the research progress of refractory metal single crystals from three aspects, preparation technology, deformation behavior, and irradiation damage, and highlights key directions for future research. Finally, future research directions are prospected to provide a reference for the design and development of refractory metal single crystals for nuclear applications. [ABSTRACT FROM AUTHOR]

Metal oxides possessing a large surface area, pore volume and desirable pore size provide more varieties and active industrial potentials. Nevertheless, it is very challenging to produce crystal metal oxides while keeping satisfactory porosity features, especially for ternary compositions. High temperature is usually needed to produce crystal metal oxides, which readily leads to the collapse of the pore structure. Herein, by employing a 'soft' dispersant agent and a hard silica template, ZrO2, TiO2 and Zr-Ti solid solutions having a tetragonal crystal structure are produced and the silica-leached materials are characterized from macroscopic to atomistic scales. The micron-sized particulate powders are composed of nanoscale 'building blocks', with crystallite sizes between ~8 and 21 nm. These polycrystalline ceramic powders exhibit a high specific surface area (up to ~200 m2·g−1) and pore volume (up to 0.5 cm3·g−1), with a pore size range of ~5–20 nm. Importantly, the Zr/Ti–O–Si–OH chemical bonds exist on the particle surface, with about two-thirds of the surface covered by silica. The hydroxyl groups can further post-graft organic ligands or directly associate with species. Synthesized mesoporous metal oxides are highly homogenous and could potentially be used in various applications because of their tetragonal structure and porosity features. [ABSTRACT FROM AUTHOR]

Pulsed laser heating of an ensemble of Pd nanoparticles, supported by a MgO substrate, is studied by x-ray diffraction. By time-resolved Bragg peak shift measurements due to thermal lattice expansion, the transient temperature of the Pd nanoparticles is determined, which quickly rises by at least 100 K upon laser excitation and then decays within 90 ns. The diffraction experiments were carried out using a Cu x-ray tube, giving continuous radiation, and the hybrid pixel detector Timepix3 operating with single photon counting in a time-of-arrival mode. This type of detection scheme does not require time-consuming scanning of the pump-probe delay. The experimental time resolution is estimated at 15 ± 5 ns, which is very close to the detector's limit and matches with the 7 ns laser pulse duration. Compared to bulk metal single crystals, it is discussed that the maximum temperature reached by the Pd nanoparticles is higher and their cooling rate is lower. These effects are explained by the oxide support having a lower heat conductivity. [ABSTRACT FROM AUTHOR]

Establishing relationships between the distribution of atoms in a crystalline unit cell and the properties of phases is an important issue directly related to the application of functional materials. In this work, we present an analysis of the crystalline structure, chemical bonds, and prediction of material properties using the example of tetragonal phases La4-4xR4xGe3S12 (R - Er, Ho, Y, Dy, Tb), which crystallize in space group R3c. The presence of rare earth elements with high coordination in the first coordination sphere is a significant contribution to changing properties, particularly thermoelectric properties. This creates the possibility of increasing the entropy factor and, as a result, improving the thermoelectric characteristics. The parameters of the elementary cell of the initial ternary phase La4Ge3S12 decrease at a ratio of 1La:1R (R - Tb, Dy, Ho, Er) in the site 6a and 18b. In the Er-containing phase, the lowest distortion index for the [M1 8S] polyhedron, while in the [M1 9S] polyhedron it significantly increases. Additionally, the formation of "columns" from polyhedra [Ge2 6S] creates the possibility of directional excitation in one direction, which can also have a significant impact on material properties. Overall, the obtained non-symmetric materials may be promising for nonlinear optics. [ABSTRACT FROM AUTHOR]

The accumulation of heavy metal ions in the human body sharply affects health, drawing global attention. Consequently, there is an urgent need to develop environmentally-friendly and non-toxic metal ion fluorescent sensing probes. Herein, two fluorescent probes based on Cs–Bi–Cl perovskite quantum dots (PeQDs) with distinct structures, namely Cs 3 BiCl 6 :Eu3+ (3-1-6-E) and Cs 3 Bi 2 Cl 9 :Eu3+ (3-2-9-E), were successfully synthesized by using the ligand-assisted re-precipitation (LARP) method for detecting Cu2+ and Fe3+ ions in ethanol. Both PeQDs exhibit polychromatic emission, including feature emission around 505 nm and distinctive emission from Eu3+ ions in the long-wavelength region, making them suitable for ratiometric fluorescent probes. Significantly, both probes displayed excellent linear relationship with correlation coefficients of 0.998 (3-1-6-E) and 0.985 (3-2-9-E), respectively. The limit of detection (LOD) reached 6.23 μM (3-1-6-E) and 4.55 μM (3-2-9-E). Notably, the 3-2-9-E quantum dots (QDs) successfully detected Fe3+ ions in ethanol, owing to their unique photo-quenching and photo-recovery phenomena. The detection results exhibited excellent linear fitting, with a correlation coefficient of 0.996 and a low LOD of 3.6 μM. Furthermore, compared to undoped PeQDs, Eu3+ ion-doped PeQDs demonstrate strongly enhanced luminescence intensity and excellent photo-stability. This work expands the potential applications of lead-free PeQDs while simultaneously improving their luminescent properties. [ABSTRACT FROM AUTHOR]

Two-dimensional single crystal metals, in which the behavior of highly confined optical modes is intertwined with quantum phenomena, are highly sought after for next-generation technologies. Here, we report large area (>104 μm2), single crystal two-dimensional gold flakes (2DGFs) with thicknesses down to a single nanometer level, employing an atomic-level precision chemical etching approach. The decrease of the thickness down to such scales leads to the quantization of the electronic states, endowing 2DGFs with quantum-confinement-augmented optical nonlinearity, particularly leading to more than two orders of magnitude enhancement in harmonic generation compared with their thick polycrystalline counterparts. The nanometer-scale thickness and single crystal quality makes 2DGFs a promising platform for realizing plasmonic nanostructures with nanoscale optical confinement. This is demonstrated by patterning 2DGFs into nanoribbon arrays, exhibiting strongly confined near infrared plasmonic resonances with high quality factors. The developed 2DGFs provide an emerging platform for nanophotonic research and open up opportunities for applications in ultrathin plasmonic, optoelectronic and quantum devices. 2D metallic single crystals are sought after for nanophotonic applications, but their synthesis remains challenging. Here, the authors report an atomic level precision etching method to fabricate large-area crystalline gold flakes with nanometre thickness, showing enhanced plasmonic and nonlinear optical properties. [ABSTRACT FROM AUTHOR]

The doping of divalent metal ions in organic crystals is used to enhance the optical properties in the present work. Pure and divalent metal ions doped anthracene single crystals are harvested using the slow evaporation solution technique in the organic solvent. The shift (≈ 0.1o) in high-intensity X-ray diffraction peak (100) reveals the structure change in doped anthracene crystals, and the Rietveld refinement of lattice parameters also confirms it. Metal ions doped anthracene crystals have enhanced the thermal stability. A blue shift in various peaks in the range of 300–450 nm of UV–Visible spectra and a broad peak in the range of 525–670 nm are observed in doped anthracene single crystals. An increment of 0.03 eV in optical energy bandgap is obtained in anthracene crystal by metal ions doping. A blue shift in all photoluminescence peaks of metal doped anthracene crystals has been seen. FESEM instrument was used to explore the growth surface and found that metal doped anthracene crystal has a smooth surface from captured images of microstructures. [ABSTRACT FROM AUTHOR]

Improving the discharge capacities of anode materials for lithium-ion batteries without sacrificing their cycling stability and rate performance at high current densities is a big challenge due to the limited Li+ diffusion kinetics and electronic conductivity. Therefore, the introduction of dissimilar metal ions into the crystal to form doping defects can effectively improve the microstructure and ion transport kinetics, thus significantly increasing the specific capacity. As an example, a new metal ion-substituted Li 2 ZnTi 3 O 8 anode material with low agglomeration and high diffusion coefficient performs a large specific capacity of 112.4 mAh g−1 at 7.0 A g−1 and good cycle stability, as well as outstanding rate performance. The obtained electrochemical performance enhancement can be attributed to guest ions changing the microscopic crystal structure, including the influence of dopant atoms on the surrounding bulk atoms and the creation of vacancies, as well as enlarged ion transport tunnels. This strategy provides an effective way to improve the eXtreme Fast Charging of the lithium-ion battery. [Display omitted] • Li 2 Zn 0.5 M 0.5 Ti 3 O 8 nanoparticles were fabricated via high temperature solid-state technique. • High diffusion coefficient and large specific capacity at 7.0 A g−1 of the Li 2 Zn 0.5 Ni 0.5 Ti 3 O 8 was demonstrated. • This strategy of dissimilar metal ion replacement provides an effective way to improve the LIBs eXtreme Fast Charging. [ABSTRACT FROM AUTHOR]

Metal halide crystals are bright but hygroscopic scintillator materials that are widely used in X‐ray imaging and detectors. Precipitating them in situ in glass to form glass ceramics (GCs) scintillator offers an efficient avenue for large‐scale preparation, high spatial resolution, and excellent stability. However, precipitating a high fraction of metal halide nanocrystals in glass to maintain high light yield remains a challenge. Herein, an ionic‐covalent hybrid network strategy for constructing GCs scintillator with high crystallinity (up to ≈37%) of BaCl2: Eu2+ nanocrystals is presented. Experimental data and simulations of glass structure reveal that the Ba2+‐Cl− clustering promotes the high crystallization of BaCl2 nanocrystals. The ultralow phonon energy (≈200 cm−1) of BaCl2 nanocrystals and good Eu reduction effect enable high photoluminescence inter quantum efficiency (≈80.41%) in GC. GCs with varied crystallinity of BaCl2: Eu2+ nanocrystals demonstrate efficient radioluminescence and tunable scintillator performance. They either outperform Bi4Ge3O14 single crystal by over 132% steady‐state light yield or provide impressive X‐ray imaging resolutions of 20 lp mm−1. These findings provide a new design strategy for developing bright transparent GCs scintillators with a high fraction of metal halide nanocrystals for X‐ray high‐resolution imaging applications. [ABSTRACT FROM AUTHOR]

Magnetohydrodynamic fluid-flows attract a lot of attention in the extrusion of polymers, in the theory of nanofluids, as well as in the consideration of biological fluids. The considered problem in the paper is the flow and heat transfer of nanoand micro-polar fluid in inclined channel. Fluid-flow is steady, while nano- and micro-polar fluids are incompressible, immiscible, and electrically conductive. The upper and lower channel plates are electrically insulated and maintained at constant and different temperatures. External applied magnetic field is perpendicular to the fluid-flow and considered problem is in induction-less approximation. The equations of the considered problem are reduced to ODE, which are analytically solved in closed form. The influence of characteristics parameters of nano- and micro-polar fluids on velocity, micro-rotation and temperature fields are graphically shown and discussed. The general conclusions given through the analysis of graphs can be used for better understanding of the flow and heat transfer of nano- and micro-polar fluid, which have a great practical application. Fluids with nanoparticles innovated the modern era, due to their comprehensive applications in nanotechnology and manufacturing processes, while the theory of micro-polar fluids explains the flow of biological fluids and various types of liquid metals and crystals. [ABSTRACT FROM AUTHOR]

Pre-edge X-ray absorption features are commonly used to derive redox states for transition metal oxides in crystals and glasses. Several calibrations for Fe2+ and Fe3+ in silicate glasses have utilized the general relationships among pre-edge peak intensity, energy, and redox state. However, absorption variations complicate those relationships in anisotropic crystals. Although absorption anisotropy at and above the energy of the rising edge adheres to the typical cos2 relationship observed in absorption spectroscopies at other energies, the anisotropy of the pre-edge is far more complicated. Prior studies focusing on pre-edge absorption anisotropy demonstrate a 1-cos4φ dependence of absorption magnitudes with rotation. Experiments presented here show that absorption magnitudes of the pre-edge vary as a function of both electric field vector orientation and wave vector direction. However, rotations around the field vector axis or wave vector axis individually result in cos2 dependence of absorption magnitudes. Rotations where both wave vector and field vector orientation are varied are not well fit by either model in the pre-edge. The resulting anisotropy complicates the process of measuring characteristic absorption in the pre-edge, making valence state determinations challenging for strongly anisotropic crystal structures such as pyroxene. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering technology plays a prominent role in spectroscopy. By introducing plasmonic metals and photonic crystals as a substrate, SERS signals can achieve further enhancement. However, the conventional doping preparation methods of these SERS substrates are insufficient in terms of metal-loading capacity and the coupling strength between plasmonic metals and photonic crystals, both of which reduce the SERS activity and reproducibility of SERS substrates. In this work, we report an approach combining spin-coating, surface modification, and in situ reduction methods. Using this approach, a photonic crystal array of SiO2@Au core–shell structure nanoparticles was prepared as a SERS substrate (SiO2@Au NP array). To study the SERS properties of these substrates, Rhodamine 6G was employed as the probe molecule. Compared with a Au-SiO2 NP array prepared using doping methods, the SiO2@Au NP array presented better SERS properties, and it reproduced the SERS spectra after one month. The detection limit of the Rhodamine 6G on SiO2@Au NP array reached 1 × 10−8 mol/L; furthermore, the relative standard deviation (9.82%) of reproducibility and the enhancement factor (1.51 × 106) were evaluated. Our approach provides a new potential option for the preparation of SERS substrates and offers a potential advantage in trace contaminant detection, and nondestructive testing. [ABSTRACT FROM AUTHOR]

Enhancing the electrical conductivity of liquid crystal (LC) circumvents challenges for application in advanced electronic components. Toward this, using additives made of different nanostructures that could result in functional LCs is suggested. In this paper, various concentrations of graphene (Gr)/metal-oxide (Fe3O4) nanocomposite (GMN) (0.0001–1 w%) were added to E7 nematic LC. We found that the role of anisotropic Gr flakes, their edges as well as surface-decorated-metal-oxide-additives have significant impact on electrical properties of E7. A range of appropriate additives of such a nanocomposite enhances the electrical conductivity of LCs. This effect can be traced through the decrease in the formation of GMN aggregates in the E7 and increase in the electrostatic field at the edges of the Gr sheets. Moreover, the presence of metal-oxide nanoclusters due to the presence of oxygen vacancies and defects facilitates the construction of conductive network for improving the charge transfer pathways and contributes to a stronger interaction of the Gr surface with charged species. These factors can provide Gr layers as dipole moments and lead to signal propagation in the dielectric medium. Our finding conveys a pathway toward significant enhancement of electrical conductivity in the LC family which can be useful for functional applications. [ABSTRACT FROM AUTHOR]

Sengon wood (Paraserianthes falcataria) is widely used in the sawmill industry. It produces waste that has not received proper handling, furthermore, innovations are needed to solve this problem, as an example as a precursor for catalyst material. This study aimed to synthesize and characterize a Co/activated carbon as a catalyst for LDPE pyrolysis. The method used is the carbonization and activation of sengon wood at 400°C and 800°C using steam, respectively. Carbon was then impregnated with 5% Co(NO3)2·6H2O. Catalyst evaluation was carried out through proximate analysis, benzene adsorption, iodine number, methylene blue adsorption, and catalyst acidity. Functional group content, morphology, crystal phase, and surface area were analyzed using FTIR, SEM-EDX, XRD, and SAA. For application, the ratio of feed: catalyst is 1:1;1:5; and 1:10. The results showed that the quality of activated carbon was 90% close to Indonesian National Standard quality. The catalyst acidity was 10,555 mmol/g with a metal crystal size of 0.56nm. Surface morphology had opened pores with the pore size, pore volume, and surface area of 2.69 nm, 0.263 cm³/g, and 329.99 m²/g respectively. LDPE cracking using a catalyst resulted in aliphatic, aromatic, and alicyclic hydrocarbon products of 48.86, 15.26, and 12.55%. Co/activated carbon catalyst has an excellent prospect for use as an LDPE cracking catalyst as a green chemical application. [ABSTRACT FROM AUTHOR]

The strict control of the work function of transition metal oxide crystals is of the utmost importance not only to fundamental research but also to applications based on these materials. Transition metal oxides are highly abundant in electronic devices, as their properties can be easily modified using redox processes. However, this ease of tuning is a double-edged sword. With the ease of manipulation comes difficulty in controlling the corresponding process. In this study, we demonstrate how redox processes can be induced in a laboratory setting and how they affect the work function of two model transition metal oxide crystals, namely titanium dioxide TiO2(110) and strontium titanate SrTiO3(001). To accomplish this task, we utilized Kelvin Probe Force Microscopy (KPFM) to monitor changes in work function, Scanning Tunneling Microscopy (STM), and Low-Energy Electron Diffraction (LEED) to check the surface morphology and reconstruction, and we also used X-ray Photoelectron Spectroscopy (XPS) to determine how the surface composition evolves. We also show that using redox processes, the work function of titanium dioxide can be modified in the range of 3.4–5.0 eV, and that of strontium titanate can be modified in the range of 2.9–4.5 eV. Moreover, we show that the presence of an oxygen-gaining material in the vicinity of a transition metal oxide during annealing can deepen the changes to its stoichiometry and therefore the work function. [ABSTRACT FROM AUTHOR]

The Ti x Zr 1-x C solid solutions were synthesized by electro-thermal explosion under pressure in the (Ti + Zr + C) blends mechanically activated in hexane (MA-ETE). The effect of mechanical activation (MA) duration on reaction blend characteristics, ETE parameters, phase composition, and microstructure formation in solid solutions was investigated. At MA, the Ti + Zr blend deforms metal crystal lattices for 20 min, complete amorphization occurs for 40 min, and the carbide grains form a cubic structure for 90 min. The single-phase Zr 0.50 Ti 0.50 C solid solution with a grain size of 3–5 μm and a submicron composite with a grain size of 0.1–0.2 μm containing the Ti 0.86 Zr 0.14 C and Zr 0.74 Ti 0.26 C solid solutions were synthesized in a one-stage process for the first time without any additional thermotreatment. The influence of mechanical activation on diffusional mass transfer of reactants, structure, and phase formation is discussed. [ABSTRACT FROM AUTHOR]

We discuss the theoretical solution to the differential equations governing accelerating edge dislocations in anisotropic crystals. This is an important prerequisite to understanding high-speed dislocation motion, including an open question about the existence of transonic dislocation speeds, and subsequently high-rate plastic deformation in metals and other crystals. [ABSTRACT FROM AUTHOR]

A synthetic method was developed to produce silver nanowires. The method utilized TBAC (tetrabutylammonium chloride) instead of conventional metal halides as crystal seed additives to obtain purer silver nanowires. Our synthesis strategy relies on accelerating the rate of seed–wire conversion. The method allows for the control of the nanowire aspect ratio by tuning the ratio of Ag+ ions to polyvinylpyrrolidone (PVP) monomer units and the molar mass of TBAC. The observed synthesis improvements meet the basic requirements of current industrial manufacturing. [ABSTRACT FROM AUTHOR]

Unveiling the structural evolution of single-crystalline compounds based on certain building units may help greatly in guiding the design of complex structures. Herein, a series of praseodymium antimony oxohalide crystals have been isolated under solvothermal conditions via adjusting the solvents used, that is, [HN(CH2CH3)3][FeII(2,2′-bpy)3][Pr4Sb12O18Cl15]·EtOH (1) (2,2′-bpy = 2,2′-bipyridine), [HN(CH2CH3)3][FeII(2,2′-bpy)3]2[Pr4Sb12O18Cl14)2Cl]·N(CH2CH3)3·2H2O (2), and (H3O)[Pr4Sb12O18Cl12.5(TEOA)0.5]·2.5EtOH (3) (TEOA = mono-deprotonated triethanolamine anion). Single-crystal X-ray diffraction analysis revealed that all the three structures feature an anionic zig-zag chain of [Pr4Sb12O18Cl15−x]n as the tertiary building unit (TBU), which is formed by interconnections of praseodymium antimony oxochloride clusters (denoted as {Pr4Sb12}) as secondary building units. Interestingly, different arrangements or linkages of chain-like TBUs result in one-dimensional, two-dimensional layered, and three-dimensional structures of 1, 2, and 3, respectively, thus demonstrating clearly the structural evolution of metal oxohalide crystals. The title compounds have been characterized by elemental analysis, powder X-ray diffraction, thermogravimetric analysis, and UV-Vis spectroscopy, and the photodegradation for methyl blue in an aqueous solution of compound 1 has been preliminarily studied. This work offers a way to deeply understand the assembly process of intricate lanthanide-antimony(III) oxohalide structures at the atomic level. [ABSTRACT FROM AUTHOR]

We conducted a systematic investigation using state-of-the-art techniques on the electronic and optical properties of two crystals of alkaline earth metal fluorides, namely rutile MgF 2 and cubic SrF 2 . For these two crystals of different symmetry, we present density functional theory (DFT), many-body perturbation theory (MBPT), and Bethe–Salpeter equation (BSE) calculations. We calculated a variety of properties, namely ground-state energies, band-energy gaps, and optical absorption spectra with the inclusion of excitonic effects. The quantities were obtained with a high degree of convergence regarding all bulk electronic and optical properties. Bulk rutile MgF 2 has distinguished ground-state and excited-state properties with respect to the other cubic fluoride SrF 2 and the other members of the alkaline earth metal fluoride family. The nature of the fundamental gaps and estimates of the self-energy and excitonic effects for the two compounds are presented and discussed in detail. Our results are in good accordance with the measurements and other theoretical–computational data. A comparison is made between the excitation and optical properties of bulk rutile MgF 2 , cubic SrF 2 , and the corresponding clusters, for which calculations have recently been published, confirming strong excitonic effects in finite-sized systems. [ABSTRACT FROM AUTHOR]

Diffusion of deuterium in indium is studied herein. In the temperature range 200–350 K, mass transfer is controlled predominantly by the mechanism of overbarrier atomic jumps; at temperatures from 80 to 120 K, by tunneling; whereas in the range from 120 to 200 K, there takes place a gradual transition from one migration mechanism to the other. These results are of fundamental significance since it is shown for the first time that quantum diffusion can be observed in a metal with a crystal lattice other than the body centered cubic one. Conditions are specified that are necessary for the observation of quantum diffusion of hydrogen: low values of Debye temperature, density of atomic packing in the lattice, and distance between the nearest equilibrium positions of hydrogen atoms. Moreover, data on the influence of point defects on hydrogen tunneling in solids are gained for the first time as well. The quantum diffusion coefficient is twice as high in the sample with enhanced vacancy concentration. [ABSTRACT FROM AUTHOR]

Single crystals of barium oxalatohydrophosphate Ba 2 (C 2 O 4)(HPO 4) were successfully synthesized by a simple solvothermal method for the first time. The crystal structure was determined from single-crystal X-ray diffraction (XRD). Ba 2 (C 2 O 4)(HPO 4) crystallizes in the monoclinic C 2 / m space group with unit cell parameters of a = 15.360(5) Å, b = 5.4418(18) Å, c = 8.969(4) Å, β = 100.48(3)°, and Z = 4. In the crystal structure of Ba 2 (C 2 O 4)(HPO 4), C 2 O 4 groups are arranged in a completely consistent orientation. Therefore, Ba 2 (C 2 O 4)(HPO 4) shows a large birefringence of 0.097 at 550 nm. UV-Vis-NIR diffuse reflectance and theory calculation show that Ba 2 (C 2 O 4)(HPO 4) is a direct bandgap semiconductor with a bandgap of 4.33 eV. Fourier transform infra-red (FTIR) and Raman spectra confirm the crystal structure of Ba 2 (C 2 O 4)(HPO 4). [Display omitted] • The first alkali-earth metal oxalatohydrophosphate crystal Ba 2 (C 2 O 4)(HPO 4) was synthesized. • Ba 2 (C 2 O 4)(HPO 4) shows a large birefringence of 0.097 at 550 nm. • Ba 2 (C 2 O 4)(HPO 4) is an direct bandgap semiconductor with a bandgap of 4.33 eV. [ABSTRACT FROM AUTHOR]

[Display omitted] • The concentration of SBS additive plays a significant role in enhancing the performance of zinc metal batteries. • The sulfonate groups in SBS vertically adsorbed on zinc surface can construct a top-down internal electric field. • SBS shows selective adsorption on Zn (002) crystal face and regulates the growth of stacked (002)-textured Zn. • SBS enhances the reversibility of zinc plating//stripping (over 4000 cycles). Aqueous Zn metal batteries face significant obstacles such as rampant Zn dendrite growth and side reactions besides their benefits. Adding trace amounts of organic additives in electrolyte is considered as an application strategy to achieve long cycling performance. In this study, sodium benzenesulfonate (SBS) composed of an electron-withdrawing sulfonate group and a benzene ring is introduced as a crystallization modulating additive into ZnSO 4 solution. We find that the saturation absorption concentration of SBS plays a key role in realizing the uniform deposition of Zn metal anode. SBS is vertically adsorbed onto Zn surface, building a top-down internal electric field that promotes the three-dimensional diffusion of Zn2+. SBS shows a crystallization modulating behavior in terms of grain nucleation, grain morphology and crystal orientation. The well-tailored crystallization structure contributes to a uniform Zn metal deposition for long cycling, which improved from 300 to 4000 cycles with the addition of SBS. At the saturation concentration of SBS, the Zn||Zn symmetric cell shows a lifespan of over 2200 h at 1 mA cm−2. This work not only provides a new option for Zn metal batteries additives but also offers new insights into the function of electrolyte additives. [ABSTRACT FROM AUTHOR]

Metal selenides obtain a series of advantages such as high electronic conductivity, excellent catalytic activity and facile fabrication approach, which are considered as promising catalysts in lithium sulfur (Li-S) battery. Traditional research based on metal selenides focuses on designing novel/complex microstructures or composites, however, the catalytic ability can be greatly affected by internal properties such as defect or vacancy. In this work, hollow nickel-cobalt layered double hydroxide (NiCo-LDH) is first fabricated and applied as a precursor to fabricate NiCoSe, and Se vacancy accompanied with crystal phase, microstructure and catalytic activity can be regulated by simply adjusting selenization atmosphere and temperature. Involving the application of NiCoSe in Li-S battery, the optimum fabrication parameter is perform the selenization at 600 °C under argon/5 % hydrogen, and the battery can exhibit a high discharge specific capacity of 1042.8 mAh g−1, excellent cycling performance of 500 cycles with a decay rate of 0.083 % at 1 C. This work highlights the importance of calcination process and also provides reference for further modifying the microstructure and performance of metal selenides in Li-S battery. [Display omitted] • The crystal phase of metal selenides can be regulated via adjusting selenization temperature. • Se vacancy can be created by calcination under reducing atmosphere. • The regulation laws of crystal phase, microstructure and catalytic activity are revealed. • The fabricated NiCoSe modified separator can provide excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Melting treatment has emerged as a promising technology for managing municipal solid waste incineration (MSWI) fly ash owing to its advantageous features of effective detoxification and volume reduction. The melting treatment of MSWI fly ash involves the immobilization of heavy metals by crystals and liquid phase. Herein, the immobilization mechanism of heavy metals (Cu, Pb and Cd) by the crystals and the liquid phase was investigated using melting experiments, thermodynamic calculations and density functional theory (DFT) calculations. Results demonstrate that the immobilization of heavy metals is influenced by a combination of factors: the reaction of heavy metals, physical encapsulation ability of the liquid phase and chemical fixation ability of both the crystals and the liquid phase. An increase in the content of SiO 2 and Al 2 O 3 promotes the conversion of heavy metals oxides into heavy metals chlorides. Furthermore, an increase in the content and polymerization degree of the liquid phase facilitates the physical encapsulation of heavy metals chlorides. The chemical fixation ability of the crystals and the liquid phase differs for Cu and Pb, while Cd cannot be immobilized through chemical fixation. To enhance the immobilization of heavy metals during melting treatment, the chemical composition of MSWI fly ash should be adjusted within the anorthite region of the ternary phase diagram. This study provides valuable insights into the immobilization mechanism of heavy metals by the crystals and the liquid phase during the melting treatment of MSWI fly ash. [Display omitted] • SiO 2 and Al 2 O 3 promote the formation of heavy metals chlorides. • Increasing liquid phase content favors physical encapsulation of heavy metals. • High liquid polymerization degree favors physical encapsulation of heavy metals. • Cu and Pb can be chemically fixed by different crystals and liquid phase. • Cd cannot be chemically fixed by crystals and liquid phase. [ABSTRACT FROM AUTHOR]

Two most common crystal structures in metals and metal alloys are body-centered cubic (bcc) and face-centered cubic (fcc) structures. The phase transitions between these structures play an important role in the production of durable and functional metal alloys. Despite their technological significance, the details of such phase transitions are largely unknown because of the challenges associated with probing these processes. Here, we describe the nanoscopic details of an fcc-to-bcc phase transition in PdCu alloy nanoparticles (NPs) using in situ heating transmission electron microscopy. Our observations reveal that the bcc phase always nucleates from the edge of the fcc NP, and then propagates across the NP by forming a distinct few-atoms-wide coherent bcc–fcc interface. Notably, this interface acts as an intermediate precursor phase for the nucleation of a bcc phase. These insights into the fcc-to-bcc phase transition are important for understanding solid − solid phase transitions in general and can help to tailor the functional properties of metals and their alloys. Phase transitions in crystals are challenging to study with atomic resolution. Here, the authors reveal that the transition from fcc to bcc occurs across a few-atoms-wide coherent interface, which serves as a precursor phase for the nucleation of the bcc phase. [ABSTRACT FROM AUTHOR]

It is important for deformation and damage resistance of lightweight engineering to develop novel lattices by additive manufacturing. In this work, we developed five novel lattice structures, tested their compressive properties from x, y, and z directions, and summarized their damage mechanisms from macro to micro view. That the pseudoplastic stress and strain trend of lattices was consistent with the plasticity trend of metal crystal, FCC > BCC > HCP, was a new discovery. Compression behaviors included the short elastic stage, the pseudoplastic stage with fluctuant peaks, and the collapse stage. Tensile and compressive damage models were used to predict lattice damage behaviors, and geometric truss and cantilever beam theories were applied to evaluate the structure stability. Lattice compression performances and damage mechanisms were clarified adequately for the first time. Besides, the geometric structure evolution and defect direction and weakening were the reasons of different compressive strength on three directions. Finally, SFCC lattices had the largest compressive strength, 155.35 MPa, in all lattices with 0.9 mm strut diameter. [ABSTRACT FROM AUTHOR]

Polycrystalline samples of the mixed cyclotriphosphates KMgP3O9, KCaP3O9, RbMgP3O9, RbCaP3O9, CsCaP3O9, and CsSrP3O9 containing Bi+ bismuth impurity monocations have been prepared via crystallization from a melt of appropriate composition. The presence of Bi+ is responsible for broadband bright near-IR luminescence in all of the materials. The shape of the photoluminescence and photoluminescence excitation spectra has been shown to be determined by the nature of the alkaline earth cation in the composition in the cyclotriphosphates and the symmetry of the local environment of the Bi+ ions under the assumption that they isomorphously substitute for alkali metal cations in the crystal lattice of the cyclotriphosphates. The characteristic photoluminescence decay time is also determined by the symmetry of the local environment of Bi+. [ABSTRACT FROM AUTHOR]

A brief historical sketch is given of Taylor's dislocation density-based model description, leading to the prediction of a parabolic, tensile, stress–strain curve for the plastic deformation of aluminum. The present focus is on additional results or analyses obtained on the subject for crystal/polycrystal strain hardening. Our current understanding of such material behavior is attributed to post-Taylor descriptions of sequential deformation stages in stress–strain measurements that are closely tied to specific dislocation interaction and reaction mechanisms. A schematic comparison is given for individual face-centered cubic (fcc), body-centered cubic (bcc), and hexagonal close-packed (hcp) crystal curves and to related strength properties determined for individual crystals and polycrystalline material. For the fcc case, an example sessile dislocation reaction is described based on a stereographic projection. Then, quantitative constitutive-relation-based assessments are presented for the tensile strain hardening leading to the plastic instability behaviors of copper and tantalum materials. [ABSTRACT FROM AUTHOR]

Moiré superlattice systems such as transition metal dichalcogenide heterobilayers have garnered significant recent interest due to their promising utility as tunable solid state simulators. Recent experiments on a WSe2/WS2 heterobilayer detected incompressible charge ordered states that one can view as generalized Wigner crystals. The tunability of the transition metal dichalcogenide heterobilayer Moiré system presents an opportunity to study the rich set of possible phases upon melting these charge-ordered states. Here we use Monte Carlo simulations to study these intermediate phases in between incompressible charge-ordered states in the strong coupling limit. We find two distinct stripe solid states to be each preceded by distinct types of nematic states. In particular, we discover microscopic mechanisms that stabilize each of the nematic states, whose order parameter transforms as the two-dimensional E representation of the Moiré lattice point group. Our results provide a testable experimental prediction of where both types of nematic occur, and elucidate the microscopic mechanism driving their formation. Recent experiments on a WSe2/WS2 hetero-bilayer detected incompressible charge ordered states considered to be generalized Wigner crystals. Here, by performing Monte Carlo simulations of a triangular moiré lattice, the authors study the phases which emerge on melting such charge-ordered states in partially filled moiré bands, finding two distinct nematic states and a hexagonal domain wall state. [ABSTRACT FROM AUTHOR]

[Display omitted] Despite the challenges on tuning the d-band structure of transition metals, the d-band is of great importance for promoting the interaction between catalytic and intermediates during the oxygen evolution reaction (OER) process. Herein, ultrafine Co nanoparticles embedded in the surface layer of nitrogen-doped carbon microspheres are prepared through an in-situ co-coordination strategy, and its d-band is modulated by introducing different Ni amounts. The introduction of Ni in the Co crystal lattice can tune the d-band center and unpaired electrons, which collectively result in an enhancement of OER activity and kinetics. By investigating the catalysts with Ni content from 0% to 75%, it is concluded that the catalyst with 25% Ni shows optimal OER activity, lower overpotential (285 mV at 10 mA cm−2) and higher current densities (73.75 mA cm−2 at 1.63 V). Moreover, the good stability is also demonstrated with the negligible decrease on current densities after 3000 CV cycles or 100 h of continuous test in alkaline media. This concept of modulating the d-band structure by introducing a transition metal with different contents in another transition metal crystal lattice could present an alternative pathway to the development of highly active catalytic materials for OER and beyond. [ABSTRACT FROM AUTHOR]

[Display omitted] • Binder-free hydrated K+ ions pre-intercalated layered MnO 2 for sodium-ion storage. • HKMO exhibits an outstanding electrochemical property in a broad potential of 3 V. • DFT calculations showed that the interlayer distance increased by intercalating K+ ions into the MnO 2 matrix. • SIS device displays an excellent specific energy with outstanding cyclability. Potassium birnessite is a remarkable material with a wider inter-planar spacing, which enables to accommodate more electrolytic ions to improve overall electrochemical performances. In this work, controlled synthesis of K 0.46 Mn 2 O4(H 2 O) 1.4 (HKMO) nanosheets were interconnected mesoporous networks uniformly grown on carbon cloth (CC) via a one-step hydrothermal process. Specifically, the HKMO sample synthesized at 100 °C for 12 h (100@HKMO-12 h) exhibited a mesoporous morphology with a large specific surface area. The binder-free 100@HKMO-12 h electrode exhibits a maximum specific capacitance of 255F g−1 (323F cm−3) in 1 M NaClO 4 /acetonitrile electrolyte over a broad potential range of 3 V. DFT studies demonstrated the interlayer distance increased by the insertion of K+ ions into the MnO 2 matrix. Bader charge analysis showed a 12.09 |e| charge difference for K-birnessite in the inter-layer region compared to the normal birnessite, supported the increase of inter-layer region in the MnO 2 matrix. Significantly, the increased interlayer the distance, promoted rapid intercalation/deintercalation of Na+ ions and allowed the reversible faradic pseudocapacitance reaction to occur at a wider potential window. Moreover, the symmetric full-cell fabricated utilizing the 100@HKMO-12 h electrodes have a wide voltage of 2 V and the device delivered a maximum specific energy of 43 Wh kg−1 (28 Wh cm−3) at a minimum specific power of 556 W Kg−1 (349 W cm−3). Besides, the device showed an excellent capacitance retention of ∼94 % even after 10,000 continuous charge–discharge cycles at a current of 5 A/g, indicating it is a potential candidate for next-generation sodium energy storage devices. [ABSTRACT FROM AUTHOR]

We have investigated the structure of χ3-borophene on Ag(111), a monolayer material of boron atoms, via total-reflection high-energy positron diffraction (TRHEPD). By comparing the experimental rocking-curves with ones for several structures calculated by using dynamical diffraction theory, we confirmed that the χ3-borophene layer has a flat structure. The distance from the topmost layer of the metal crystal is 2.4 Å, which is consistent with results reported by X-ray standing wave-excited X-ray photoelectron spectroscopy. We also demonstrated that the in-plane structure of χ3-borophene is compatible with the theoretical predictions. These structural properties indicate that χ3-borophene belongs to a group of epitaxial monolayer sheets, such as graphene, which have weak interactions with the substrates. [ABSTRACT FROM AUTHOR]

Cu 0.06 MnO 2 ·1.7H 2 O and Bi 0.09 MnO 2 ·1.5H 2 O with nanoflower structures were designed and prepared by a simple one-step hydrothermal method, which will be applied for cathode material of aqueous zinc ion battery. The pre-intercalated metal ions and water molecules serve as pillars to improve the stability of layered structure and the migration rate of zinc ions. [Display omitted] • Two kinds of cathode materials of Cu 0.06 MnO 2 ·1.7H 2 O (CuMO) and Bi 0.09 MnO 2 ·1.5H 2 O (BiMO) with nanoflower structure were designed by a facile one-step hydrothermal method. • The pre-intercalated metal ions and water molecules serve as pillars to sustain the layered structures of these materials. • The metal ions and crystal water are beneficial to improve the migration rate of zinc ions. • The layered structure of the BiMO cathode can be effectively sustained by the incorporation of hydrated Bi3+, and the specific capacity of the CuMO cathode can be finally enhanced by the incorporation of hydrated Cu2+. For aqueous zinc ion batteries (AZIBs), birnessite MnO 2 (δ-MnO 2) has been intensively used as one of the most potential cathode materials due to its layered structure, which is conducive to reversible insertion/extraction of zinc ions. However, δ-MnO 2 has not been attained for zinc ion storage performance because of its inferior conductivity as well as the undesirable structural degradation upon charge/discharge cycling. Herein, we have designed two kinds of cathode materials of Cu 0.06 MnO 2 ·1.7H 2 O (CuMO) and Bi 0.09 MnO 2 ·1.5H 2 O (BiMO) with nanoflower structure for the first time by a facile one-step hydrothermal method, which will be applied for high-performance AZIBs.The pre-intercalated metal ions and water molecules serve as pillars to sustain the layered structures, improving the stability of these materials. Particularly, the CuMO may experience a replacement reaction except the zinc ion insertion/extraction to form metallic Cu during the cycling process, which can enhance the diffusion rate of Zn2+, thus resulting in an excellent electronic conductivity and exhibiting remarkable specific capacities. Furthermore, a pseudo-capacitance that is derived from the surface-adsorbed Cu2+and Bi3+ also contributes to the improved electrochemical performances. The reversible capacity of CuMO is estimated as 350 mAh g−1 at 0.5 A g−1, which is much higher than that of pure δ-MnO 2 (190 mAh g−1 at 0.5 A g−1). However, BiMO demonstrates long-term cycling stability, maintaining a capacity of 114.5 mAh g−1 even after 1100 charged-discharged cycles at 1 A g−1. The capacity retention is found to be as high as 98.6%, which is much higher than that of pure δ-MnO 2 (53.8%). This can contribute to the development of high-performance AZIBs and the application of metal ion pre-intercalation methods in other areas. [ABSTRACT FROM AUTHOR]

By the x-ray diffractometry method, the authors found a change in the crystal structure of a number of metals in the zone of exposure of their surface to laser radiation with a flux density of 104–105 W/cm2. It has been shown that on exposure of the surface of metal samples to laser radiation, their crystal structure changes, in the exposed zone, from the equilibrium structure to a distorted one (having the shape of a parallelepiped, which is different from a cube). A relationship has been assumed between the disclosed effect and the occurrence of considerable microstresses in the zone of rapid anisotropic heating of metals. [ABSTRACT FROM AUTHOR]

In this work, a compact model is presented for a 14-nm CMOS-based fin resonant body transistor (fRBT) operating at a frequency of 11.8 GHz and targeting radio frequency (RF) generation/filtering for next-generation radio communication, clocking, and sensing applications. Analysis of the phononic dispersion characteristics of the device, which informs the model development, shows the presence of displacement component coupling due to the periodic nature of the back-end-of-line (BEOL) metal phononic crystal (PnC). An eigenfrequency-based extraction process, applicable to resonators based on electrostatic force transduction, has been used to model the resonance cavity. Augmented forms of the Berkeley short channel IGFET model (BSIM)-common multigate (CMG) model for FinFETs are used to model the drive and sense transistors in the fRBT. This model framework allows easy integration with the foundry-supplied process design kits (PDKs) and circuit simulators while being flexible toward change in transduction mechanisms and device architecture. Ultimately, the behavior is validated against RF measured data for the fabricated fRBT device under different operating conditions, leading to the demonstration of the first complete model for this class of resonant device integrated seamlessly in the CMOS stack. [ABSTRACT FROM AUTHOR]

[Display omitted] Rechargeable aqueous zinc–ion batteries (RAZIBs) have received increasing attention due to cost−effectiveness and inherent safety. A wide variety of advanced cathode materials have been revealed with promising performance in RAZIBs. However, these materials usually require sophisticated procedures at high temperatures, which greatly limit further practical application. Herein, a chimie douce approach is adopted to prepare vanadium oxides from V 2 O 5 suspension with the addition of various transition metal cations (Mn2+, Zn2+, Ag+, and Fe3+) by simple liquid−solid mixing under ambient conditions. For the cases of Mn2+ and Zn2+, the dissolution−recrystallization process takes place leading to layered Mn 0.31 V 3 O 7 ·1.40H 2 O (MnVO) and Zn 0.32 V 3 O 7 ·1.52H 2 O (ZnVO). The use of Ag+ forms tunneled Ag 0.33 V 2 O 5 (AgVO), and the present of Fe3+ stays mainly unreacted V 2 O 5. The underlying reaction chemistries are proposed, for which the pH values of precursor solutions are found to be a key factor. Among the prepared materials, layered vanadium oxides exhibit promising battery performance. Particularly, MnVO delivers 340 and 217 mAh g−1 at 1 and 8 A g−1, respectively. A specific capacity of 164 mAh g−1 can be retained after 500 cycles at 1 A g−1. By contrast, AgVO and FeVO demonstrate inferior performance with retaining only 89 and 20 mAh g−1 after 500 cycles. [ABSTRACT FROM AUTHOR]

In this article, new insights about the metals-porphyrin complexes are proved by analyzing the zinc, nickel and chromium adsorption process over the well-known porphyrin macromolecule. The use of the quartz crystal microbalance (QCM) apparatus allows the control of the complexation systems' experimental adsorption data operating at four temperatures. The experimental results and the physical models reveal that the zinc and nickel complexation processes are to be examined using the mono layer adsorption model. While, the double layer model describes the interaction between the chromium compound and the porphyrin. Actually, the three metals are shown to be adsorbed by a multi-docking process in the physicochemical description. The endothermic character of the investigated processes is shown through the appropriate data of the principal parameter adsorbent sites' density. Hence, several porphyrin sites are exclusively stimulated at high temperature. The parameters of van del Waals, depicting the influences of the lateral interactions, explain the nickel isotherms down trend. The chemical bonds are shown to be carried out between the zinc and the porphyrin through the calculated adsorption energies. Considering the thermodynamic study, and referring to the configurational entropy and the free enthalpy, it is to be noted that the disorder peak of the three mechanisms is reached when the equilibrium concentration is equal to the energetic parameters' values for each system. The nickel enthalpy revealed for high concentration that the adsorbates' lateral interactions disapproved the nickel chloride adsorption. The free enthalpy trends, that observed two stability states of the chromium compound, confirmed the chromium double layer mechanism. [ABSTRACT FROM AUTHOR]

Monolayer transition metal dichalcogenide crystals (TMDCs) hold great promise for semiconductor optoelectronics because their bound electron-hole pairs (excitons) are stable at room temperature and interact strongly with light. When TMDCs are embedded in an optical microcavity, excitons can hybridise with cavity photons to form exciton polaritons, which inherit useful properties from their constituents. The ability to manipulate and trap polaritons on a microchip is critical for applications. Here, we create a non-trivial potential landscape for polaritons in monolayer WS2, and demonstrate their trapping and ballistic propagation across tens of micrometers. We show that the effects of dielectric disorder, which restrict the diffusion of WS2 excitons and broaden their spectral resonance, are dramatically reduced for polaritons, leading to motional narrowing and preserved partial coherence. Linewidth narrowing and coherence are further enhanced in the trap. Our results demonstrate the possibility of long-range dissipationless transport and efficient trapping of TMDC polaritons in ambient conditions. Room-temperature exciton polaritons in a monolayer WS2 are shown to display strong motional narrowing of the linewidth and enhanced first-order coherence. They can propagate for tens of micrometers while maintaining partial coherence, and display signatures of ballistic (dissipationless) transport. [ABSTRACT FROM AUTHOR]

In this paper, high-purity and fine (W0.2V0.2Ta0.2Nb0.2Ti0.2)B2 (HEB) powders were obtained via a simple high-energy ball milling-assisted boro/carbothermal reduction method at 1600°C. Results showed that the heating temperature and B source contents played a key role in the synthesis of purity of single-phase HEB powders. When excess 10 wt.% B4C was introduced, the single-phase HEB powders were synthesized at 1600°C, and its grain size was ~150 nm and it showed the hexagonal crystal structure of metal diborides. EDS results showed the high compositional uniformity of W, V, Ta, Nb, Ti and B elements in HEB powders. Through discussing the thermodynamics process related to these possible chemical reactions and combining the XRD results at different temperatures, it was obtained that higher temperature and enough B source were required to stimulate the formation of high-entropy phase. This work will be a vital step for the commercialization of high-entropy boride powders. [ABSTRACT FROM AUTHOR]