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Molybdenum (Mo) is a strategic metal for the manufacture of aerospace equipment, satellite components, and vehicle armor. Thus, understanding its behaviors under harsh conditions like shock compression is crucial for its practical utilization. Through molecular dynamic simulations, we have explored the mechanical responses and microstructural evolutions of nano-polycrystalline (NPC) Mo under different shock intensities, with grain sizes ranging from 5 to 33 nm. Our study reveals that grain size considerably influences the Hugoniot data and waveform of NPC Mo. NPC Mo with a smaller grain size exhibits higher compressibility and lower Hugoniot shear stress. As the grain size increases, the presence of a double-wave structure becomes more pronounced. Additionally, with the increase in shock intensity, there is a reduction in the shock front width. Significantly, when the shock stress ranges from approximately 60 to 100 GPa, twinning structures are detected in samples with grain sizes ranging from 10 to 33 nm. Moreover, the elevated temperature behind the shock wave further promotes detwinning reactions. When the shock stresses exceed 100 GPa, twinning–detwinning as well as amorphization-recrystallization become the predominant deformation mechanisms, almost unaffected by grain size. As the shock stress exceeds 250 GPa, the atoms in the samples become completely disordered. These findings provide new insights into the mechanical responses as well as the microstructural evolutions of NPC Mo under shock compression. [ABSTRACT FROM AUTHOR]

We present the ab initio thermoelastic properties of body-centered cubic molybdenum under extreme conditions obtained within the quasi-harmonic approximation including both the vibrational and electronic thermal excitation contributions to the free energy. The quasi-harmonic temperature-dependent elastic constants are calculated and compared with existing experiments and with the quasi-static approximation. We find that the quasi-harmonic approximation allows for a much better interpretation of the experimental data, confirming the trend found previously in other metals. Using the Voigt–Reuss–Hill average, we predict the compressional and shear sound velocities of polycrystalline molybdenum as a function of pressure for several temperatures, which might be accessible in experiments. [ABSTRACT FROM AUTHOR]

The surface properties of nickel-based alloys with different alloying compositions against aggressively corrosive species were systematically evaluated by using the segregated and non-segregated models designed through first-principles calculations. The presence of typical VIB alloying elements such as chromium (Cr), molybdenum (Mo), and tungsten (W) elements near the nickel surface was identified to significantly enhance the surface adsorption of water molecules (H2O) and their decomposed products (OH, O, and H). The doping patterns and surface electronic structures were found to determine the adsorption diversity of these substances. Consequently, adsorbates containing oxygen were likely to induce the segregation tendencies of these selected alloying elements from the deep area of nickel toward the top-most surface layer (TSL). The electrode potential shifts of the surface Ni atom in the designed alloying systems, compared to the bare Ni (111) surface, were further calculated to identify the beneficial electrochemical performance of alloy surfaces in the absence/presence of various adsorbates. In vacuum, the locations of these alloying elements in the near-surface layers would more increase the electrode potential shifts, thereby delaying the dissolution of Ni atoms from metal substrates. Nevertheless, the presence of adsorbates led to notably negative electrode potential shifts for the Ni (111) surface, among which the decomposed products (hydroxyl and oxygen) were of the most passive effects on corrosion behavior of nickel. The detrimental effects of these adsorbates on surface stability would be effectively alleviated with the aid of atomic VIB alloying elements of nickel-based alloys, especially W segregation to the TSL regardless of the pH in aqueous environments. [ABSTRACT FROM AUTHOR]

By electric transport measurements on high-purity bulk molybdenum single crystals at helium-temperature, it is shown that when approaching the ideal metallic crystal structure, there are deviations from Ohm's law that can exceed 30% even at low current densities ≅ 3 A / m m 2. This is due to the intrinsic circular magnetic field of the measuring current in the range of B ≅ 1 mT , which generates a magnetoresistance according to the two-band conduction model. With increasing lattice vibrations and/or crystal defects, this inherent uncertainty finally reduces to immeasurably small values. Finally, Ohm's law for a nearly ideal lattice structure can be strictly exact only in the theoretical limiting case of an infinite lattice plane, because then the magnetic fields of all electrons of the current compensate to zero. [ABSTRACT FROM AUTHOR]

Since the form of the exact functional in density functional theory is unknown, we must rely on density functional approximations (DFAs). In the past, very promising results have been reported by combining semi-local DFAs with exact, i.e. Hartree–Fock, exchange. However, the spin-state energy ordering and the predictions of global minima structures are particularly sensitive to the choice of the hybrid functional and to the amount of exact exchange. This has been already qualitatively described for single conformations, reactions, and a limited number of conformations. Here, we have analyzed the mixing of exact exchange in exchange functionals for a set of several hundred isomers of the transition metal carbide, Mo4C2. The analysis of the calculated energies and charges using PBE0-type functional with varying amounts of exact exchange yields the following insights: (1) The sensitivity of spin-energy splitting is strongly correlated with the amount of exact exchange mixing. (2) Spin contamination is exacerbated when correlation is omitted from the exchange-correlation functional. (3) There is not one ideal value for the exact exchange mixing which can be used to parametrize or choose among the functionals. Calculated energies and electronic structures are influenced by exact exchange at a different magnitude within a given distribution; therefore, to extend the application range of hybrid functionals to the full periodic table the spin-energy splitting energies should be investigated. [ABSTRACT FROM AUTHOR]

Since the form of the exact functional in density functional theory is unknown, we must rely on density functional approximations (DFAs). In the past, very promising results have been reported by combining semi-local DFAs with exact, i.e. Hartree–Fock, exchange. However, the spin-state energy ordering and the predictions of global minima structures are particularly sensitive to the choice of the hybrid functional and to the amount of exact exchange. This has been already qualitatively described for single conformations, reactions, and a limited number of conformations. Here, we have analyzed the mixing of exact exchange in exchange functionals for a set of several hundred isomers of the transition metal carbide, Mo4C2. The analysis of the calculated energies and charges using PBE0-type functional with varying amounts of exact exchange yields the following insights: (1) The sensitivity of spin-energy splitting is strongly correlated with the amount of exact exchange mixing. (2) Spin contamination is exacerbated when correlation is omitted from the exchange-correlation functional. (3) There is not one ideal value for the exact exchange mixing which can be used to parametrize or choose among the functionals. Calculated energies and electronic structures are influenced by exact exchange at a different magnitude within a given distribution; therefore, to extend the application range of hybrid functionals to the full periodic table the spin-energy splitting energies should be investigated. [ABSTRACT FROM AUTHOR]

Potentially toxic elements (PTEs) were determined in raw milk from Nigerian cattles (cow, goat and sheep), to assess the environmental pollution, impact on milk quality and health risk. Nine composite samples were collected from five states in Northwest Nigeria, being the major cattle breeders. The samples were wet digested and PTEs determined using ICP-OES. 45 PTEs were ascertained of which Nitrogen (43754 mg/L) and Strontium, Sr (0.007 mg/L) recorded the highest and least mean concentration respectively. The mean concentration of other PTEs were: Selenium (0.253 ± 0.077), Cadmium (0.040 ± 0.0411), Mercury (0.048 ± 0.037), Silver (0.088 ± 0.013), Arsenic (0.044 ± 0.006), Boron (0.056 ± 0.005), Aluminium (0.014 ± 0.002), Tin (0.109 ± 0.019), Lead (0.018 ± 0.006), Gold (0.088 ± 0.048), Manganese (214.8 ± 18.754), Iron (473.9 ± 55.901), Zinc (247.9 ± 15.874), Copper (84.5 ± 12.905), Nickel (0.0031 ± 0.001), Molybdenum (0.459 ± 0.160), Cobalt (0.055 ± 0.020), Chromium (0.028 ± 0.008), Vanadium (0.185 ± 0.051), Calcium (24988 ± 16302), Magnesium (5733 ± 1460.8), Potassium (6555 ± 1199.6), Sodium (17.59 ± 2.914), Phosphorus (497.2 ± 90.38), Bismuth (0.055 ± 0.032), Cerium (0.048 ± 0.043), Argon (0.083 ± 0.011), Silicon (0.265 ± 0.110), Sulphur (0.087 ± 0.009), Titanium (0.073 ± 0.030) and Bromine (0.021 ± 0.005). Others are Platinum (0.021 ± 0.008), Antimony (0.088 ± 0.007), Iodine (0.16 ± 0.022), Caesium (0.374 ± 0.037), Barium (0.025 ± 0.009), Lanthanum (0.115 ± 0.182), Samarium (0.150 ± 0.095), Palladium (1.47 ± 0.991), Curium (0.042 ± 0.009), Fermium (0.036 ± 0.0098), Americium (0.826 ± 0.618) and Rubidium (0.048 ± 0.044). The Pearson's correlation and paired sample t-test showed that most of the PTEs have similar origin at 0.05% significant level, and all the cattle had the same level of exposure to the PTEs respectively in the area. Raw milk is about 80% water and so, the determined PTEs concentrations are considered very high in the analyzed samples. The presence of Pb in the milk is a concern since Pb is a toxin at any concentration. The high content of PTEs in milk is attributed to the indiscriminate and artisanal mining activities in the region, and the fact that the animals are free rangers. The health risk factors were below unity (HR < 1) and so were not potential hazards. However, the environmental contaminations by these PTEs are very substantial and if this type of milk is taken raw or used for the production of dairy products like cheese and butter, then there may be a serious health condition on the consumer since they are not biodegradable. [ABSTRACT FROM AUTHOR]

This work proves that the Mo-doping is an efficient strategy for boosted NH 4 +-storage of VO 2 (B). Mo-doped VO 2 (B) delivers the specific capacitance of 1403 F g−1 (390 mAh g−1) at 0.1 A g−1. This strategy is like a Chinese idiom "like adding wings to a tiger" to guide the design of electrode materials for high-efficient NH 4 +-storage. [Display omitted] Supercapacitors (SCs) using ammonium-ion (NH 4 +) as the charge carrier (NH 4 +-SCs) have attracted continuous attention and vanadium-based materials are proved to have high-efficient NH 4 +-storage properties. Monoclinic vanadium dioxide, VO 2 (B), as an anode material applied to SCs has been rarely reported and modulating its electronic structure for boosted NH 4 +-storage is full of challenge. In this work, molybdenum-doped VO 2 (B) (Mo-doped VO 2 (B)) is designed and synthesize to enhance its NH 4 +-storage. The introduction of Mo atom into the crystal structure of VO 2 (B) can modulate its crystal structure and bring in some defects. Experimental results manifest that Mo-doped VO 2 (B) with 2 % Mo-doping shows the best electrochemical properties. Mo-doped VO 2 (B) achieves the specific capacitance of 1403 F g−1 (390 mAh g−1) at 0.1 A g−1 and the capacitance retention of about 98 % after 5000 cycle, superior to that of VO 2 (B) (893 F g−1, 248 mAh g−1 at 0.1 A g−1 and 60 % capacitance retention. The hybrid supercapacitor (HSC) assembled by Mo-doped VO 2 (B) and active carbon delivers good electrochemical performance with the energy density of 38.6 Wh kg−1 at power density of 208.3 W kg−1. This work proves that the Mo-doping is an efficient strategy for boosted NH 4 +-storage of VO 2 (B) and this strategy is like a Chinese idiom "like adding wings to a tiger" to guide the design of electrode materials for high-efficient NH 4 +-storage. [ABSTRACT FROM AUTHOR]

The metastable phase molybdenum carbide-based (α-MoC 1-x) catalysts stand out as a class of the most promising representatives among the non-sulfide catalysts for the synthesis of higher alcohols (HAS) from syngas (CO/H 2) due to their noble metal-like characteristics, resistance to coking, sulfur tolerance and weak C–O bond dissociation. However, the synthesis of α-MoC 1-x commonly involves temperature-programmed ammonification and carburization (TPAC) or the consumption of noble metals. The α-MoC 1-x prepared by TPAC usually exhibited large particle size, low dispersion and poor catalytic performance. Herein, we developed a facile and continuous thermal plasma method for synthesizing nanosized α-MoC 1-x , which was highly dispersed on amorphous carbon (α-MoC 1-x /C-Pla). Compared with the α-MoC 1-x prepared by TPAC method (α-MoC 1-x -TPAC), the α-MoC 1-x /C-Pla catalyst exhibited higher CO conversion and excellent stability. The high dispersion and reactant adsorption/desorption capacity of α-MoC 1-x /C-Pla contributed to its high catalytic activity, while the anti-aggregation property of the nanosized α-MoC 1-x in α-MoC 1-x /C-Pla conferred the high stability for the α-MoC 1-x /C-Pla catalyst. [Display omitted] • A facile and continuous method for synthesizing α-MoC 1−x /C-Pla was developed. • Nanosized α-MoC 1−x particles were well dispersed on carbon in α-MoC 1−x /C-Pla. • α-MoC 1−x /C-Pla exhibited high activity and stability for syngas to higher alcohols. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry," published by The Royal Society of Chemistry. It includes various papers and communications on topics such as catalysts, metal-organic frameworks, and semiconductor materials. The journal aims to connect the world with the chemical sciences and invest profits back into the chemistry community. [Extracted from the article]

Deposition of dome-shaped metal–organic complexes on metallic surfaces to produce well-defined single site catalysts is a novel approach combining aspects of homogeneous and heterogeneous catalysis. In order to investigate the bonding of small molecules to such systems, a molybdenum(0) tricarbonyl complex supported by a thiacalix[3]pyridine is synthesized and deposited on Au(111) and Ag(111) surfaces by vacuum evaporation. The resulting mono- and submonolayers are investigated with surface spectroscopy and STM. All of these methods indicate a parallel orientation of the molybdenum complex with respect to the surface. The vibrational properties and frequency shifts of the adsorbed complexes with respect to the bulk are evaluated with the help of conventional IR and IRRA spectroscopy, coupled to DFT calculations. Compared to a similar Mo(0) tricarbonyl complex supported by an azacalixpyridine ligand, the title complex exhibits a higher stability in the bulk and adsorbed to surfaces which goes along with a lower reactivity towards oxygen. [ABSTRACT FROM AUTHOR]

Single‐site molybdenum dioxo catalysts, fullerenol/MoO2, are prepared via grafting precursor (DME)MoO2Cl2 onto a highly polyhydroxylated fullerene (ful) and an isomerically‐pure and well‐defined fullerene (ful*). These catalyst structures are characterized by ICP‐OES, XPS, XANES, EXAFS, DRIFT, Raman, and NMR spectroscopy, and DFT. Mo 3d5/2 XPS and Mo K‐edge XANES assign the oxidation state as Mo(VI). Mo EXAFS data fitting reveals two Mo=O double and two Mo−O single bonds at distances of 1.7 and 1.9 Å, respectively, while an Mo=O stretchingl mode is observed at ~950 cm−1 by DRIFT and Raman spectroscopy. These data align well with DFT computational results, supporting the proposed catalyst structure as Fullerene(‐μ‐O‐)2M(=O)2. Additionally, DFT provides insight into the energetically favorable grafting sites for an isomerically pure fullerenol. The scope of fullerenol/MoO2 mediated alkene epoxidation includes abiotic alkenes, natural occurring terpenes, and conjugated olefins. For cyclooctene the rate law is first‐order in [Mo], near first order in [olefin] and zero‐order in [t‐butyl hydroperoxide]. A plausible reaction mechanism involves peroxide addition first and then cyclooctene addition directly across the peroxo bond forming the epoxide product, consistent with DFT computation. Overall, fullerenol/MoO2 shows promise as a sustainable and structurally well‐defined system with versatile catalytic activity and good epoxidation recyclability. [ABSTRACT FROM AUTHOR]

The first Lewis acid base adducts of MoF6 and an organic base have been synthesized, i. e., MoF6(NC5H5) and MoF6(NC5H5)2. These adducts are structurally characterized with X‐ray crystallography, showing that both adducts adopt capped trigonal prismatic structures. The MoF6(NC5H5) and MoF6(NC5H5)2 adducts are fluxional on the NMR time scale at room temperature. Two different fluorine environments could be resolved by 19F NMR spectroscopy at −80 °C for the 1 : 2 adduct, MoF6(NC5H5)2, whereas MoF6(NC5H5) remains fluxional at that temperature. Density functional theory (DFT) calculations aide the assignment of the infrared and Raman spectra. Natural Bond Order and Molecular Electrostatic Potential analyses elucidate the structures and properties of the MoF6 pyridine adducts. Regions of significantly higher molecular electrostatic potential, i. e., σ‐holes, in trigonal prismatic compared to octahedral MoF6 rationalize the capped trigonal prismatic geometry of the adducts. Whereas MoF6(NC5H5) is stable at room temperature under exclusion of moisture, MoF6(NC5H5)2 decomposes at 60 °C in pyridine solvent, and the solid slowly decomposes at room temperature after 24 h. [ABSTRACT FROM AUTHOR]

The first Lewis acid base adducts of MoF6 and an organic base have been synthesized, i. e., MoF6(NC5H5) and MoF6(NC5H5)2. These adducts are structurally characterized with X‐ray crystallography, showing that both adducts adopt capped trigonal prismatic structures. The MoF6(NC5H5) and MoF6(NC5H5)2 adducts are fluxional on the NMR time scale at room temperature. Two different fluorine environments could be resolved by 19F NMR spectroscopy at −80 °C for the 1 : 2 adduct, MoF6(NC5H5)2, whereas MoF6(NC5H5) remains fluxional at that temperature. Density functional theory (DFT) calculations aide the assignment of the infrared and Raman spectra. Natural Bond Order and Molecular Electrostatic Potential analyses elucidate the structures and properties of the MoF6 pyridine adducts. Regions of significantly higher molecular electrostatic potential, i. e., σ‐holes, in trigonal prismatic compared to octahedral MoF6 rationalize the capped trigonal prismatic geometry of the adducts. Whereas MoF6(NC5H5) is stable at room temperature under exclusion of moisture, MoF6(NC5H5)2 decomposes at 60 °C in pyridine solvent, and the solid slowly decomposes at room temperature after 24 h. [ABSTRACT FROM AUTHOR]

We found that molybdenum carbide (Mo2C) can be applied as a novel and efficient heterogeneous catalyst for hydrogen transfer of anilines and alcohols to synthesize N-alkylamines. The results of experiments and DFT calculations demonstrate that Mo2C surface can reduce the energy barrier of the key step of alcohol dehydrogenation and generate a hydrogen spillover effect, thereby exhibiting outstanding catalytic performance. [ABSTRACT FROM AUTHOR]

The layered double hydroxides (LDHs) electrocatalysts have emerged as promising electrocatalysts for electrolytic water splitting due to their simple synthesis, high activity. However, traditional LDH-based catalysts face the low electrical conductivity and durability under electrolysis conditions. In this work, Mo–CoFe LDH was prepared by a two-step hydrothermal method, and the effect of different molybdenum content on its catalytic performance was studied. Among them, the OER and HER properties of Mo-CoFe LDH-1 are better than those of non-Mo doping. Mo–CoFe LDH-1 has the low HER and OER overpotentials are 192 mV and 134 mV, respectively at 10 mA cm−2. In addition, using Mo–CoFe LDH-1 for water splitting can achieve a low voltage of 1.55 V at 10 mA cm−2, and it also showed a good stability within 100 h. The excellent properties of Mo–CoFe LDH-1 is mainly due to the formation of 3D nanoflower structure and the doping of Mo element in CoFe LDH, significantly adjusting its electronic structure. This work is of great significance for the design of bifunctional LDHs-based electrocatalysts. We designed Mo–CoFe LDH electrocatalyst by two-step hydrothermal method. Due to Mo element introduction, which changes the surface electronic environment of CoFe LDH and increases the surface catalytic active site. Mo–CoFe LDH-1 exhibits excellent HER and OER bifunctional performances, as well as good long-term stability during overall water splitting. [Display omitted] • Mo element doping into CoFe LDH nanoflower was achieved via hydrothermal method. • The catalyst excels HER and OER properties, making it a strong contender for stable the overall water splitting. • It holds promise as an eco-friendly catalyst for green electrolytic water technology. [ABSTRACT FROM AUTHOR]

A study was carried out to determine the concentration of heavy metals and trace elements in milk and dairy products collected from local farms, supermarkets, or food retailers in the region of Lazio (Central Italy). Persistent exposure to metal contamination is of particular concern for human health, as it can cause different serious disorders. The monitoring of the matrices studied is therefore important, given their high consumption in the daily diet. The elements determined by ICP-MS (Inductively Coupled Plasma – Mass Spectrometry) were lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), chromium (Cr), nickel (Ni), molybdenum (Mo) and thallium (Tl), for a total of 151 measurements in 98 samples. The results showed that 11.3% of the measurements were quantifiable but below the legal maximum limits (MLs) set by EU regulations. The data obtained may be useful for dietary exposure information, inter-regional comparisons and for planning regional surveillance strategies. [ABSTRACT FROM AUTHOR]

The pressure limit of the conventional cubic press is normally below 6 GPa, and the suitable pressure calibrant of the fixed-point method is scarce. In this study, we developed a new method for pressure determination using an acoustic travel time approach. Based on the reported ultrasonic travel times of polycrystalline molybdenum under high pressure in literature, an acoustic gauge of polycrystalline molybdenum was derived. The shear wave travel times of molybdenum were measured at high pressures and utilized for the pressure calibration in a cubic press. The pressures derived from this new travel time method are in excellent agreement with those from the fixed-point method. Subsequent compressional and shear wave velocities of polycrystalline tungsten were measured up to about 5 GPa at room temperature to further verify this method. This travel time method for pressure calibration is valuable for the sound velocity measurement of other materials in an offline laboratory. [ABSTRACT FROM AUTHOR]

Until now, there have been many reports on the regulation of inorganic metal ions on the catalytic activity of nanozymes, but few reports on the regulation of anions (such as NO2−) on enzyme activity. In this work, a copper-molybdenum doped carbon dots (Cu, Mo-CDs) with peroxidase-like (POD) activity was synthesized by simple one-step microwave digestion method. The Cu, Mo-CDs + NO2− system can promote 3,3′,5,5′-tetramethylbenzidine (TMB) oxidizing to blue oxidative product (oxTMB) due to the formation of ∙NO2 free radical. While Hg2+ was introduced into the system, the POD-like activity of Cu, Mo-CDs + NO2− system was inhibited due to the strong interaction and the electron transfer between Cu, Mo-CDs and Hg2+. The formation of ∙NO2 and the electron transfer capability of Cu, Mo-CDs + Hg2+ were confirmed through ESR spectra and FMN experiments. The bioenzyme-free colorimetric assay based on Cu, Mo-CDs nanozyme is used for detection of NO2− and Hg2+, showing lower detection limit (LOD) of 1.63 µg/L for NO2−, 0.13 µg/L for Hg2+, respectively and good recovery from 90.79 to 108.90%. The work paves a new way to design a nanozyme-based colorimetric protocol for traces NO2− and Hg2+ residues in food analysis. [ABSTRACT FROM AUTHOR]

The Yellow River basin is rich in sediment that provides a transport carrier for the transport and diffusion of pollutants. Molybdate ions contained in the tributaries of the Yellow River are dispersed with the water and sediment movement to the whole basin, which will result in water pollution and soil pollution within a certain range. The static adsorption method is adopted to study the adsorption of molybdate ions onto the Yellow River sediment, the adsorption model of molybdate on sediment can be obtained from the experimental data and kinetic analysis can be carried out to lay a good foundation for exploring molybdenum adsorption and removal in actual water flow. The effects of contact time, pollutant concentration, sediment concentration, and agitation frequency on the molybdenum adsorption onto sediment were investigated. In the process of sediment-molybdenum adsorption, the kinetics and isothermal adsorption conformed to the Lennard-Jones equation model and the Freundlich model, respectively. Simultaneously increasing the molybdenum concentration, sediment content, and agitation frequency enhances the adsorption of molybdate onto sediment particles. Higher concentrations within a specific range have a more pronounced effect. [ABSTRACT FROM AUTHOR]

The NiCrMoSiC composite cladding on Titan-31 base alloy was produced using a hybrid microwave heating process. The produced claddings were examined for microstructural, phase analysis, microhardness, and surface roughness using suitable techniques. The linear reciprocator ball on plate wear test was conducted using a static alumina indenter on microwave cladding. Studies have been done on track specifications for friction and wear. It is feasible to fabricate a dense microstructure with uniform distribution of hard phases, absence of pores and fractures, and strong metallurgical bonds. Typically, cladding is two times as durable as the underlying metal. The cladding has a lower coefficient of friction than the substrate as a result of enhanced hardness and improved internal lubricity brought on by the production of hard carbide phases. [ABSTRACT FROM AUTHOR]

Molybdenum (Mo) plays an important role in maintaining plant growth and human health. Assessment studies on the driving factors of Mo migration in soil-crop systems are crucial for ensuring optimal agricultural and human health. The Mo bioconcentration factor (BCF-Mo) is a useful tool for evaluating Mo bioavailability in soil-crop systems. However, the influence pathways and degrees of different environmental factors on BCF-Mo remain poorly understood. In this context, 109 rhizosphere and maize grain samples were collected from the Longitudinal Range–Gorge Region (LRGR) in Linshui County, Sichuan Province, China, and analyzed for the contents of Mo and other soil physiochemical parameters to explore the spatial patterns of BCF-Mo and its driving factors. Areas with the highest BCF-Mo values were mainly observed in the southern and northern parts of the Huaying and Tongluo mountains. The influence degrees of the selected environmental factors in this study followed the order of normalized difference vegetation index (NDVI) < elevation (EL) < mean annual humidity (MAH) < slope (SL) < mean annual temperature (MAT). The MAH and NDVI directly influenced the BCF-Mo values. The EL and MAT mainly indirectly affected the BCF-Mo values by influencing the rhizosphere organic matter (OM) contents, while the SL mainly affected the BCF-Mo values by influencing the rhizosphere pH. Therefore, OM and pH of the rhizosphere were the main influencing factors of BCF-Mo in the study area. In summary, the selected environmental factors mainly exhibited indirect influences on BCF-Mo by directly affecting the physicochemical properties of the rhizosphere. [ABSTRACT FROM AUTHOR]

This paper presents experimental studies on mechanical properties and micro-structures of ultra-high performance concrete (UHPC) made of recycled molybdenum tailings. The particle size distribution and chemical compositions of recycled molybdenum tailings were analysed at first. Then, compressive and flexural tests were conducted on UHPC in which different volume fractions of recycled molybdenum tailings were used to replace silica sand. The effects of recycled molybdenum tailings replacement ratio on the compressive and flexural strengths were determined through comparisons. Besides, X-ray diffraction tests and backscattered electron tests were carried out to analyse the effect of molybdenum tailings on the micro-structure of UHPC. Based on test data, an optimal replacement ratio of molybdenum tailings was determined which could significantly reduce the cost of UHPC but maintain the mechanical properties in compression. A molybdenum tailings replacement ratio of 30% was recommended to maximise the economic effect and to reduce the carbon emission. [ABSTRACT FROM AUTHOR]

The physical properties of two-dimensional (2D) van der Waals (vdW) materials are profoundly influenced by their stacking orders, which affect interlayer coupling and crystal symmetry, leading to fascinating strongly correlated orders. Detecting stacking orders is important, yet challenging as they involve sub-nanometer shifts in the relative arrangement of layers. In this study, we utilize nanomechanical resonators to detect the strain change during the stacking order transition of octahedrally coordinated thin molybdenum ditelluride (MoTe2) membranes and show the change in stacking orders can be reflected by the vibration modes of nanomechanical resonators. We discover that a strain as small as 0.014%—induced by transitions in the stacking order—results in a notable frequency shift up to 1.019 MHz in the mechanical resonance. We establish the relationship between the detection sensitivity of stacking orders and both internal and external parameters including higher-order vibrations, electrostatic energy, and initial strain. Our nanomechanical methodology offers a potential avenue for creating a comprehensive phase diagram by uncovering stacking orders across a wide array of van der Waals materials and leveraging ultralow-barrier stacking order transitions for energy-efficient devices. [ABSTRACT FROM AUTHOR]

Strong metal‐support interaction (SMSI) between transition metal nanoparticles and carbon matrix offers significant structure advantages due to the ability to modulate the electronic structure of metal nanoparticles, increase the density of active sites, and improve the conductivity of catalysts. Here, ultrafine nanoparticles of metallic molybdenum compounds (MoP, Mo2C, and MoS2) strongly coupled with mesoporous carbon CMK‐5 are synthesized. The confinement growth of nanoparticles in the pores of CMK‐5 produces encapsulated nanoparticles, affording facilitated electron transfer, and enhancing the HER activity induced by the SMSI effect. The hierarchical nanostructure and strong electronic interactions between the carbon substrate and molybdenum‐based nanoparticles allow efficient mass/electron transport between the carbon substrate and molybdenum‐based nanoparticles, improving the catalytic hydrogen evolution reaction (HER) activity. The effective electron exchange between the Mo species and the CMK‐5 support is studied by X‐ray photoelectron spectroscopy (XPS) measurement, confirming the presence of the SMSI effect. The resulting MoP/CMK‐5 catalyst exhibits outstanding HER performance in alkaline (65 mV@10 mA cm−2), acidic (123 mV@10 mA cm−2), and simulated seawater electrolytes (103 mV@10 mA cm−2), making it one of the most promising catalysts reported for HER. This work provides guidance on designing high‐performance electrocatalysts with SMSI for the enhancement of the electrochemical reaction. [ABSTRACT FROM AUTHOR]

Sluggish redox kinetics and severe polysulfide shuttling are major hurdles for the commercialization of lithium–sulfur (Li–S) batteries. Transition‐metal compound catalysts offer a promising solution by providing excellent polysulfide adsorption capabilities, outstanding catalytic activities, and homogeneous nucleation control of Li2S2/Li2S. The electronic structure of transition‐metal sites in catalysts can also be fine‐tuned through bi‐metallic coupling, which can further improve the catalytic activities. In this study, bi‐metallic nickel molybdenum phosphide is co‐synthesized with Li2S and carbon through a carbothermal reduction process, forming a cathode composite (Li2S @ NixMoyPz @ C). This process is not only advantageous for large‐scale manufacturing due to its simplicity, but also ensures homogeneous integration and distribution of the catalyst within the cathode composite. Furthermore, applying Li2S as an active material allows the creation of an anode‐free cell configuration, enhancing the overall cell energy density. The anode‐free cell with the Li2S @ NixMoyPz @ C composite cathode demonstrates an outstanding capacity retention of 50% over 300 cycles at a negative‐to‐positive capacity (N/P) ratio of 1. Additionally, the bi‐metallic phosphide integrated Li2S cathode composite delivers a remarkable anode‐free pouch cell performance of 703 mA h g−1 (on Li2S basis) under the challenging conditions of an E/Li2S ratio of 4.5. [ABSTRACT FROM AUTHOR]

In this work, we report the thermoelectric behaviour of flexible fabric-based Mo doped CuAl 2 O 4. The doped Mo atom occupies the interstitial positions of the spinel lattice of CuAl 2 O 4. This results the lattice expansion and also provides the carrier electrons. Initially, the pristine CuAl 2 O 4 has the carrier concentration of 2.81 × 1014 cm−3, while doping with molybdenum, it not only increases the concentration of the carriers (about −7.65 × 1015 cm−3), but also changes the carrier type. The minimum doping (2 %) of molybdenum to spinel CuAl 2 O 4 (CuAl 2 O 4 Mo 0.02) creates the fermi level near to the conduction band, which reduces the band gap and results in the effective electrical conductivity as 0.69 Scm−1 at 340 K. The heavy doping enhances the scattering process. This leads to deduction of mobility and lower the electrical conductivity. The highest power factor of 0.0599 μWcm−1K−2 is achieved for the CuAl 2 O 4 Mo 0.06 sample at 300 K. This is due to the high Seebeck coefficient value of the sample and has an ultralow thermal conductivity value of 0.056 W/mK. The highest output voltage of 3.9 mV is achieved for parallelly connected p-type CuAl 2 O 4 -n-type CuAl 2 O 4 Mo 0.02 thermoelectric device at the temperature difference of ΔT = 4.1 K. This research findings justify, the doping of molybdenum in the spinel lattice effectively enhances the thermoelectric properties of CuAl 2 O 4 and provide the new ideas for the flexible, wearable fabric based thermoelectric research. [Display omitted] [ABSTRACT FROM AUTHOR]

Reaction of neutral olefin complexes of ruthenium and molybdenum with GaTMP (TMP = 2,2,6,6-tetramethylpiperidinyl) by substitution leads to the formation of respective five- and six-coordinated homoleptic products. [Ru(GaTMP)5] (1) and [Mo(GaTMP)6] (2) were isolated and characterized. Core structure geometries were analyzed using continuous shape measure, and the complexes were subjected to DFT calculations unveiling competing π-interactions between the transition metal center and the amido substituent with the unoccupied pπ orbitals of the gallium. [ABSTRACT FROM AUTHOR]

Despite the importance of alkaline seafloor hydrothermal vents in broadening our understanding of deep-sea hydrothermal ecosystems, little is known about the mobility and concentrations of micronutrient transition metals in these environments. Here, we present new analyses of micronutrient transition metal concentrations in vent fluids from the iconic Lost City Hydrothermal Field (LCHF) and report concentrations of Fe = 2.9–18.3 µmol/kg, Zn = 1.30–5.86 µmol/kg, Cu = 0.43–5.06 µmol/kg, Ni = 86.4–556 nmol/kg, Mn = 8.3–274 nmol/kg, V = 25.9–127 nmol/kg, Mo = 24–94 nmol/kg, Co = 8.0–135 nmol/kg, W = 4.8–16 nmol/kg, and Cd = 1.7–4.5 nmol/kg. We additionally present results of a hydrothermal lherzolite alteration experiment conducted at 300 °C, 500 bar. Transition metal concentrations and major chemical parameters of experimental reaction fluids are broadly similar to LCHF vent fluids, indicating that transition metal concentrations in LCHF vent fluids, and alkaline hydrothermal fluids more generally, reflect metal solubility controlled by underlying rock-buffered hydrothermal reactions. Concentrations of Ni and Mo are especially noteworthy because of their recognized importance for biological methanogenesis (Ni) and nitrogen fixation (Mo). When compared with known biological thresholds, our findings indicate that Ni concentrations in LCHF vent fluids are sufficient to support the robust methane-metabolizing microbial communities observed in the immediate vicinity of LCHF vents and suggest that Ni availability influences the spatial distribution of LCHF methanogens. Furthermore, our laboratory hydrothermal experiments demonstrate that Mo concentrations of similar magnitude to those observed in LCHF vent fluids (and also modern seawater) can be obtained by hydrothermal alteration of ultramafic rocks with Mo-free (Na, Ca) Cl aqueous solution. Thus, we conclude that alkaline hydrothermal fluids were likely similarly enriched in Mo prior to oxidation of the Earth's atmosphere and ocean, providing localized Mo-rich geochemical environments capable of supporting Mo-dependent nitrogen fixation at currently recognized threshold concentrations. [ABSTRACT FROM AUTHOR]

Peanut optimal planting density is necessary to obtain the maximum yield. Also, peanut as heavy feeder of nutrients needs to be supplemented through foliar application and bio-fertilizer (BF) plays an important role in food safety and sustainable production. This experiment was done in Rasht, Iran, during the 2017–2018 and 2018–2019 cropping seasons and carried out as split-factorial based on randomized complete blocks design with three replications. Three planting densities including 83,333 (PD1), 100000 (PD2) and 125,000 (PD3) plants ha−1 in main plot, four levels of BF including no application of BF as control (Z0) as check, Rhizobium spp. (RB), Arbuscular mycorrhizal fungi (AMF) and the combined application of RB + AMF and three treatments of magnesium (Mg), molybdenum (Mo) and Mg + Mo as factorial 4 × 3 in sub plot, comprised experimental treatments. The tripartite interaction of PD2 × (RB+AMF) × (Mg+ Mo) produced the greatest seed yield (3515 kg ha−1), pod yield (4472 kg ha−1), biological yield (9380 kg ha−1), oil yield (1515 kg ha−1) and protein yield (793 kg ha−1). Also, the application of AMF along with Mo fertilizer increased the content of OA (58.51%) and SA (4.43%) in PD1 treatment. According to the results of this experiment, the inoculation of RB + AMF along with foliar application of Mg + Mo in PD2 treatment enhanced the SY of peanut and combined application of AMF and Mo improved oil quality in PD1 treatment and be recommended to enhance quantitative and qualitative yield of peanut under similar climatic conditions. [ABSTRACT FROM AUTHOR]

Weather and climate uncertainties significantly impact crop and food production, particularly in the Bihar region of India. Crop cultivation in this region faces significant risks due to several climatic challenges: rising minimum temperatures in the winter (rabi), extreme temperatures in the spring, intense rainfall, and extended dry spells during the kharif ;(monsoon) season. The growth and development of the plants majorly depend on the climatic and nutrient factors. The plant uptake and utilization of nutrients are surprisingly reliant on the weather conditions. Therefore, understanding the interaction of climatic factors and nutrient application methods is crucial for achieving higher growth and yield stewardship. A two-year field experiment was conducted from 2019 to 2021 in the riverine area (Diara) of Bihar, India, to evaluate the relationship between weather parameters and application methods of Molybdenum and Boron on the dry matter production (DMP) and grain yield of chickpea. Six different application methods of Boron and Molybdenum were tested. The study aimed to identify the ideal micronutrient application methods for chickpea production in the rabi season under the Diara ;(riverine) area. Results indicated that the combination of boron basal + molybdenum seed treatment produced the highest grain yield (1740 kg ha−1) and dry matter production (5.81 g plant−1) at all phenological phases, performing on par with boron basal + molybdenum foliar application for both years. Concerning the weather parameters, the correlation studies showed that all the direct weather parameters and agrometeorological indices showed positive and negative effects (p =.05) on DMP and grain yield of chickpea during both years. This study contributes to the development of site-specific application methods for molybdenum and boron, identifies optimal sowing times, minimizes the negative impacts of climate change, and maximizes chickpea production in the riverine (Diara) area of Bihar. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A novel electrocatalyst, Ni‐Co/β‐Mo2C@C, was rationally designed to enhance the efficiency of the hydrogen evolution reaction (HER) in this work. Assembled with two‐dimensional Ni‐Co nanosheets onto Mo2C nanorods coated with a thin carbon shell, the catalyst demonstrates remarkable performance, including low overpotential (η10 = 57 mV) and reduced Tafel slope (63 mV·dec–1) in 0.5 mol·L–1 H2SO4 electrolyte. This innovative design strategy provides abundant active sites and efficient electron/ion transport pathways, effectively shortening reactant diffusion distances and enhancing electrocatalytic activity. Additionally, the carbon shell coating protects the catalyst from etching and agglomeration, ensuring its durability. This work presents a promising approach for engineering highly efficient metal carbide‐based HER catalysts through tailored composition and nanostructure design. [ABSTRACT FROM AUTHOR]

The limitation of water and unfavorable soil conditions for plant's nutrient absorption present a hurdle to the growth and yield of red beans under drought stress conditions. Micronutrients, particularly zinc and molybdenum, show promise in mitigating drought effects. Various irrigation levels (100% and 70% of field capacity) and nutrient application methods were tested in the field (two locations) and the greenhouse in 2022. Parameters such as photosynthesis, gas exchange, root characteristics, nitrate reductase, antioxidant enzymes, and yield were evaluated. The combination of nano zinc priming (NZnP 150 mg L−1) and foliar spraying of nano zinc (FSNZn 0.04 mg L−1) at 100% field capacity resulted in the highest photosynthesis, gas exchange, and yield. Water stress increased the activity of antioxidant enzymes. In greenhouse test, NZnP (150 mg L−1) + FSNZn (0.04 mg L−1) at 100% field capacity promoted maximum root length and nitrate reductase activity. Overall, NZnP + FSNZn at 100% field capacity proved most effective for morphological and biochemical root characteristics and yield. Drought stress reduced red bean yield, but NZnP + FSNZn mitigated some adverse effects. Nano forms of zinc and molybdenum were more effective in mitigating drought stress. Location significantly influenced plant development, with lower temperatures delaying reproductive phase transition, leading to better vegetative and reproductive traits compared to the location with higher temperature. [ABSTRACT FROM AUTHOR]

Maintaining a consistently high current density growth rate in the hydrogen evolution reaction is highly challenging because the limited mass transfer rate at the electrode/electrolyte interface will make the adsorption reaction as the rate‐determining step associated with a low hydrogen coverage, exhibiting a Tafel slope >120 mV dec–1. Therefore, maximizing the current density range in which the desorption reaction is the rate‐determining step, can significantly reduce the overpotential. Herein, a surface sulfur decoration strategy is presented to modify the molybdenum carbide electrocatalyst and achieve coordinated adsorption/desorption kinetics, leading to a dominant Volmer–Heyrovsky mechanism across a wide range of current densities. Both experimental and theoretical results validate the surface charge redistribution induced by sulfur decoration, which subtly optimizes the Gibbs free energy of hydrogen adsorption and enhances the in‐plane polarization field. As a result, the as‐obtained surface sulfur‐decorated molybdenum carbide electrocatalyst exhibits coordinated adsorption/desorption kinetics and efficient hydrogen delivery, ultimately surpassing the commercial Pt/C electrocatalyst for high‐efficiency hydrogen evolution. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A novel electrocatalyst, Ni‐Co/β‐Mo2C@C, was rationally designed to enhance the efficiency of the hydrogen evolution reaction (HER) in this work. Assembled with two‐dimensional Ni‐Co nanosheets onto Mo2C nanorods coated with a thin carbon shell, the catalyst demonstrates remarkable performance, including low overpotential (η10 = 57 mV) and reduced Tafel slope (63 mV·dec–1) in 0.5 mol·L–1 H2SO4 electrolyte. This innovative design strategy provides abundant active sites and efficient electron/ion transport pathways, effectively shortening reactant diffusion distances and enhancing electrocatalytic activity. Additionally, the carbon shell coating protects the catalyst from etching and agglomeration, ensuring its durability. This work presents a promising approach for engineering highly efficient metal carbide‐based HER catalysts through tailored composition and nanostructure design. [ABSTRACT FROM AUTHOR]

The reliable connection between ceramics and metals achieved through brazing is a crucial method to promote their application. In this study, the FeCoCrNi high entropy alloys was adopted as the filler to connect SiC and Mo through vacuum brazing. The microstructure evolution and mechanical properties of the SiC/FeCoCrNi/Mo brazed joint at different brazing temperature and holding time were systematically investigated. With the increase of the brazing temperature or the extension of the holding time, the reaction layer gradually thickened with the increasing precipitation of the soft FCC phase. Notably, the FCC solid solution phase with good plastic deformation ability and the brittle Cr 0.46 Mo 0.4 Si 0.14 phase have good interface bonding (lattice mismatch degree ∼ 3.12 %). The dispersive and staggered distribution of FCC phase and Cr 0.46 Mo 0.4 Si 0.14 phase can effectively alleviate the joint stress and hinder crack propagation. This work is expected to provide theoretical guidance for the connection of ceramics and metals through high-entropy alloys. [ABSTRACT FROM AUTHOR]

This study reviews the progress and challenges in developing rapid colorimetric and turbidimetric test kits for commercial soil nutrient analyses, focusing on nitrogen, phosphorus, and potassium. Although common laboratory analytical techniques are accurate, they are often expensive and require advanced technical skills. Consequently, commercial in situ soil test kits have gained attention as potential alternatives to these tests. These kits use universal extractants that can simultaneously extract multiple nutrients and colorimetry and turbidimetry for nutrient determination. A critical aspect of these kits is the selection of suitable extractants that are effective under various soil conditions, chemically safe, compatible with analytical systems, and have a long shelf life. This review assesses the efficacy of several extractants in conjunction with colorimetric and turbidimetric reagents. Examples include H3A-4 and Kelowna extractants using the zinc–Griess reagent, salicylic method, molybdenum yellow method, and sodium tetraphenyl boron method for nitrate, ammonium, phosphorus, and potassium, respectively. These extractants and reagents have been highlighted for their adaptability, safety, rapid color formation, and minimal compatibility issues, making them promising candidates for rapid test kit development. However, rapid soil test kits are designed to provide a general understanding of soil nutrient status. They are not intended to replace detailed laboratory analyses in situations where precision is critical. Additionally, these kits should be validated against standard laboratory methods to determine their accuracy and reliability. This review highlights the importance of balancing practicality and accuracy when developing rapid soil test kits for soil nutrient analysis. [ABSTRACT FROM AUTHOR]

We perform structural investigations of a molybdenum-based cermet material obtained by the method of selective electron-beam melting. The initial material is an alloy of the Mo–Si–B system alloyed with a reinforcing component in the form of an Al2O3–Y2O3–ZrO2 oxide composition. It is shown that, in the process of selective electron-beam melting of spheroidized cermet particles of the alloy of Mo–Si–B system in the optimal technological mode of synthesis, we observe melting both of the molybdenum matrix of the alloy and of the reinforcing particles contained in the original granules. As a result, in the course of crystallization of the melt with formation of a cellular structure on the boundaries of cells, we observe the appearance of finely divided oxide particles 1–5 μm in size, which are also composite particles. On the boundaries of cells and inside oxide inclusions, we reveal the elevated content of silicon as compared to that in the body of cells, which enables us to conclude that the processes of diffusion of this element occur in the analyzed material. At the same time, in the vicinity of the contour of samples of synthesized material, we detect the formation of a structure, which inherits, to a certain extent, the structure of the initial spheroidized granules. [ABSTRACT FROM AUTHOR]

Laser‐quality yttrium‐aluminum garnet single crystals doped with neodymium (YAG:Nd) of a concentration up to 1 at. % is grown by the method of horizontal directional crystallization from a molybdenum crucible in the protective reducing atmosphere based on argon, СО, and hydrogen. It is found that the content of carbon impurity in the grown crystals does not exceed 5·10−3 wt %, the content of molybdenum being on the level of 1.5·10−3 wt %. The optical quality of the crystals depends on the composition of the growth atmosphere and annealing. It is shown that, besides the bands of neodymium ion absorption, the crystals are characterized by the intense absorption in the UV edge of the spectrum at 370 nm wavelength, and by the wide absorption band with a maximum at 580 nm caused by formation of F and F+‐centers. The absorption at 370 and 580 nm can be eliminated by annealing. The structure perfection of the crystals is characterized by the rocking curve half‐width (β) which value varies within the limits of 10–14 arc. sec for (001) plane. Laser testing demonstrates the parameters comparable with those of YAG:Nd crystals grown by the Czochralski method from iridium crucible. [ABSTRACT FROM AUTHOR]

We present a method of creating high-density superconducting flexible wiring on flexible thin silicon substrates. The flexible wiring, called SOI flex, is created by depositing superconducting wiring on a silicon-on-insulator (SOI) wafer, selectively etching away the thicker silicon section handle layer, and bending the thinner silicon device layer. We show measurements of superconducting transition temperature and critical current for Mo, Nb, and Al on SOI flex. We discuss the expected advantages of SOI flex for low-temperature detector applications, as well as the role of stress and strain in bent silicon and niobium. [ABSTRACT FROM AUTHOR]

• Different levels of drought stress result in changes in gene expression and reduce plant growth and development. • The proper concentration of nutrients can increase plant efficiency under stress and normal conditions. • Molybdenum can lead to dryness adjustment through different pathways, including the accumulation of osmolytes, increasing the activity of enzymes and reducing the content of oxidative markers. Drought stress is a multidimensional abiotic stress that negatively affects plant growth and yield. Therefore, identifying useful, low-cost, and low-risk solutions to deal with drought along with identifying tolerant plants is crucial for sustainable agriculture and crop production worldwide. In some cases, due to a lack of nutrients, even if there is enough moisture, the plants are still unable to absorb water. Increasing essential macro- and micronutrients may reduce the harmful effects of abiotic stresses, among which drought, while increasing yield. The essential element molybdenum (Mo) has a role in many processes such as photosynthesis, nitrogen (N) metabolism, hormone signaling and tolerance of abiotic stresses. Plants absorb Mo as molybdate anion (MoO 4 2−), which is the main common soluble form of Mo present in neutral to alkaline soils. Mo has a unique effect on the synthesis of hormones and enzymes, and thus affecting plant water relationships and response to environmental stresses. On the other hand, limited water resources and lack of access to adequate water for agricultural production in terms of quantity and quality risk compromising the uptake of Mo which is already critical in soils acidic and/or poor in this essential micronutrient. This study systematically investigated the response to Mo stress and provided valuable evidence for the efficacy of Mo as a candidate to temper the adverse effects of drought stress on crops. Further, this review article also explains the mechanistic actions exerted by Mo in alleviating the drastic effects of drought on crops. [ABSTRACT FROM AUTHOR]

We have been developing a novel 99Mo/99mTc generator production method using a water-insoluble porous MoO2 target. In this method, the extraction of 99mTc from MoO2 is achieved by leveraging the difference in their water solubilities. The fabrication of a porous MoO2 pellet, and the water extraction of 99mTc from neutron irradiated porous MoO2 were conducted. The results confirmed 99mTc extraction with a low Mo/Tc ratio. Additionally, the dissolution rate of radioactive 99Mo was found to be higher than stable isotopes of molybdenum, i.e., confirming the hot atom effect on the dissolution of molybdenum in (n, γ ) reaction. [ABSTRACT FROM AUTHOR]

Development of high capacity and long cycle life electrode materials is essential to improving energy storage capacity in electrochemical rechargeable devices. In order to be commercially viable, the synthesis of these materials must be straightforward, cost-effective, and ideally a single-step process. We present a binder-free synthesis method for nickel phosphate hydrate (NiPH) and nickel molybdenum phosphate hydrate (NiMoPH) on nickel foam via a simple hydrothermal process. X-ray diffraction (XRD) patterns confirmed the formation of NiPH and NiMoPH phases, while X-ray photoelectron spectroscopy (XPS) verified the presence of nickel (Ni), molybdenum (Mo), phosphorus (P), and oxygen (O) in the composite. Scanning electron microscopy (FE-SEM) revealed the formation of micro-flowers with plate-like structures in NiPH, which transformed into hexagonal rod-like structures upon the introduction of molybdenum in NiPH. This morphological and phase modification increased the charge storage capacity from 1441 mF/cm2 (NiPH) to 2945 mF/cm2 (NiMoPH) at 20 mA/cm2. The NiMoPH electrode demonstrated excellent capacitance retention of 91.8 % over 10,000 cycles. Additionally, asymmetric supercapacitor (ASS) devices were fabricated using NiPH and NiMoPH as positive electrodes and activated carbon (AC) as the negative electrode. The NiPH//AC and NiMoPH//AC configurations exhibited energy densities of 0.086 and 0.201 mWh/cm2, respectively, with the NiMoPH//AC device maintaining about 90 % capacitance retention over 15,000 cycles. This study demonstrates the potential of incorporating conductive transition metals to enhance electrode material performance in energy storage applications. Hydrothermally synthesized nickel phosphate hydrate (NiPH) and nickel molybdenum phosphate hydrate (NiMoPH) electrode materials for energy storage devices have been reported. The transformation of NiPH microplates into hexagonal rods upon the addition of molybdenum was observed. This structural modification and improved conductivity, induced by the inclusion of molybdenum, enhances the electrochemical energy storage performance of the electrodes. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study focuses on the effect of molybdenum and nitrogen on the microstructure and mechanical properties of VC x O y -Fe cermets. Samples with 0–23 at% Mo were fabricated using a wet synthesis route and heat treatment under Ar and N 2 atmospheres. Phase transformations during heating were investigated by TGA-DSC in combination with XRD, and the resulting materials were analyzed by SEM/EDX. A doping level of 6–12 at% was found to be optimal, as it lowered the melting point of the metallic binder to 1320–1360 °C. Replacing argon with nitrogen further decreased the melting point to 1210–1240 °C and reduced the grain size. Depending on the sintering temperature, gas environment, and molybdenum content, the produced cermets were characterized by 92–97 % density, 17–29 vol% binder phase, 8–14 GPa hardness, and 6–9 MPa m0.5 fracture toughness. The average size of oxycarbide grains, their stoichiometry, and the amount of dissolved vanadium in the iron binder demonstrated a strong correlation with changes in mechanical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • ·Mo 2 C-FeCu catalyst was designed by thermal reduction and carburization of precursor. • ·cinnamaldehyde/benzalacetone were synthesized at high yields and selectivities. • · α , β -unsaturated aldehyde/ketone were electrosynthesized in gentle and green manner. • ·C C coulping reaction was fulfilled by combined electrochemical-chemical pathway. Oxygen evolution reaction (OER) is the efficiency limiting half-reaction in water electrolysis for green hydrogen production due to the 4-electron multistep process with sluggish kinetics. The electrooxidation of thermodynamically more favorable organics accompanied by C C coupling is a promising way to synthesize value-added chemicals instead of OER. Efficient catalyst is of paramount importance to fulfill such a goal. Herein, a molybdenum iron carbide-copper hybrid (Mo 2 C-FeCu) was designed as anodic catalyst, which demonstrated decent OER catalytic capability with low overpotential of 238 mV at response current density of 10 mA cm−2 and fine stability. More importantly, the Mo 2 C-FeCu enabled electrooxidation assisted aldol condensation of phenylcarbinol with α -H containing alcohol/ketone in weak alkali electrolyte to selective synthesize cinnamaldehyde/benzalacetone at reduced potential. The hydroxyl and superoxide intermediate radicals generated at high potential are deemed to be responsible for the electrooxidation of phenylcarbinol and aldol condensation reactions to afford cinnamaldehyde/benzalacetone. The current work showcases an electrochemical-chemical combined C C coupling reaction to prepare organic chemicals, we believe more widespread organics can be synthesized by tailored electrochemical reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel 1 T/2H-MoSe 2 /CN-TH dual-homojunction photocatalyst was designed for photocatalytic CO 2 reduction. • The intramolecular CN-TH homojunction could promote intralayer charge separation and migration. • The tandem multi-step charge transfer channel is achieved to accelerate the charge transfer dynamics. • The 1 T/2H-MoSe 2 /CN-TH exhibits a high CO yield of 27.36 μmol·g-1·h-1. Due to the high dissociation energy of carbon dioxide (CO 2) and sluggish charge transfer dynamics, photocatalytic CO 2 reduction with high performance remains a huge challenge. Herein, we report a novel dual-homojunction photocatalyst comprising of cyano/cyanamide groups co-modified carbon nitride (CN-TH) intramolecular homojunction and 1 T/2H-MoSe 2 homojunction (denoted as 1 T/2H-MoSe 2 /CN-TH) for enhanced photocatalytic CO 2 reduction. In this dual-homojunction photocatalyst, the intramolecular CN-TH homojunction could promote the intralayer charge separation and transfer owing to the strong electron-withdrawing capabilities of the two-type cyanamide, while the 1 T/2H-MoSe 2 homojunction mainly contributes to a promote interlayer charge transport of CN-TH. This could consequently induce a tandem multi-step charge transfer and accelerate the charge transfer dynamics, resulting in enhanced CO 2 reduction activities. Thanks to this tandem multi-step charge transfer, the optimized 1 T/2H-MoSe 2 /CN-TH dual-homojunction photocatalyst presented a high CO yield of 27.36 μmol·g−1·h−1, which is 3.58 and 2.87 times higher than those of 1 T/2H-MoSe 2 /CN and 2H-MoSe 2 /CN-TH single homojunctions, respectively. This work provides a novel strategy for efficient CO 2 reduction via achieving a tandem multi-step charge transfer through designing dual-homojunction photocatalyst. [ABSTRACT FROM AUTHOR]

Two series of non-hydrogenated diamond-like carbon (DLC) films and molybdenum doped diamond-like carbon (Mo-DLC) films were grown on the silicon substrate using direct current magnetron sputtering. The influence of molybdenum doping (between 6.3 and 11.9 at.% of Mo), as well as the deposited temperature (between 185 and 235 °C) on the surface morphology, elemental composition, bonding microstructure, friction force, and nanohardness of the films, were characterized by atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and a nanoindenter. It was found that the increase in the metal dopant concentration led to a higher metallicity and graphitization of the DLC films. The surface roughness and sp3/sp2 ratio were obtained as a function of the Mo concentration and formation temperature. The nanohardness of DLC films was improved by up to 75% with the addition of Mo. Meanwhile, the reduction in the deposition temperature decreased the nanohardness of the DLC films. The friction coefficient of the DLC films was slightly reduced with addition of the molybdenum. [ABSTRACT FROM AUTHOR]

Joining dissimilar materials, such as Ti and Mo, faces several difficulties due to the differences in their material properties. Dissimilar materials are commonly joined through high-temperature brazing. This paper investigates the characteristics of high-temperature brazing of Ti with Mo. Brazing alloys Ti-18Cu-11Ni-7Zr-9Be-1 V and Zr-30Ti-25Be-10Cu at.% were used to braze Mo and Ti alloys at 815 °C for 10 min, followed by slow cooling. EDS analysis investigations reveal multiple zones and phases in the joint. Solid solutions of α-(Ti) and β-(Ti), (Ti, Zr)2(Ni, Cu) and Be-based intermetallics formed in the brazed joints. Based on the results of EDS analysis and phase diagrams, the paper proposes the microstructure evolution and phase transformation mechanism during brazing process. [ABSTRACT FROM AUTHOR]

The works of assessing the pollution posed by metals in agricultural areas in developing countries are limited. This study aims to assess metal concentrations and pollution indices of parent materials and soils representing the mantle and oceanic crust units of the ophiolite in the Eastern Mediterranean region, specifically in Kahramanmaraş Province. A total of 88 samples, comprising 44 soil (0–30 cm) and 44 parent material (90 + cm), were collected from the study area. Arsenic (As), mercury (Hg), selenium (Se), uranium (U), molybdenum (Mo), tin (Sn), and cesium (Cs) concentrations were analyzed in these samples, along with the reference metal, iron (Fe). Pollution levels were assessed using enrichment factor (EF) and contamination factor (CF) calculations. Results showed that elemental concentrations (Hg, Se, U, Mo, Sn, and Cs) in soils from the mantle and oceanic crust generally reflected those of the parent material. However, the average As concentration in soils from oceanic crust and mantle units was notably elevated, showing a 3 to fourfold increase compared to the parent material. Based on pollution index values, soils from these units demonstrated a moderate level of enrichment (2 < EF < 5) for As, while other elements (Hg, Se, U, Mo, Sn, and Cs) fell into the low enrichment class (EF < 2). Furthermore, the CF index indicated significant contamination (3 < CF < 6) for As. These findings suggest As contamination in soils from different units of the ophiolite (mantle and oceanic crust), potentially resulting from agricultural chemicals like pesticides and fertilizers. [ABSTRACT FROM AUTHOR]