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Nanoparticles play an important role in the properties of metallic glasses (MGs) due to their diversified structures; however, their structure–property relationship is unclear. In this paper, three ex situ metallic glass matrix composites were assembled by three kinds of nanoparticles and Cu50Co50 MG obtained by rapid cooling, and their structural evolution under uniaxial compression is investigated by molecular dynamic simulation. It is found that the activated atoms always preferentially accumulate in the amorphous region near the embedded nanoparticles (ENPs). ENPs hinder the propagation of shear bands and lead to strain-hardening behavior. The fractal structures convert the HCP and tDh atoms into atoms of other structures to improve the anti-deformation ability, and the parallel-twin structure improves the anti-deformation ability through the mutual conversion of the FCC and HCP atoms. These findings provide a new idea for improving the mechanical properties of MGs. The change in the ENP structure provides theoretical support for the design of composite materials with specific requirements for structural evolution. [ABSTRACT FROM AUTHOR]

We investigate the glassy-state properties of Mg2Ca, Al2Ca, and Al4Ca from the grafting application viewpoint. We employed classical molecular dynamics to examine the phase transition, structural, thermodynamic, transport, and mechanical properties in the amorphous state. All properties suggest successful simulations of the glass phase at and below the glass transition temperature, ranging between 550 and 689 K for Mg2Ca, Al2Ca, and Al4Ca. Computed results are compared and discussed with the reported findings and known mechanical and thermal properties of the various parts of the human bones and biocomposites. The comparison establishes that the mechanical, thermal, and transport properties significantly improve in the glass phase compared to its crystalline alloy form. At 300 K, studied glasses have densities in close agreement with human bone density. Structural analysis and heat capacity show the second-order phase transition, verifying the formation of the glass structure. The targeted glasses exhibit excellent thermal conductivity and thermal diffusivity compared to other commonly used biocomposites for bone grafting. Furthermore, the simulated elastic properties, viz., the Poisson ratio, G/B ratio, Cauchy's pressure, and yield strength, are in close agreement with the mechanical properties of various parts of human bone. The predicted ductility nature, contrary to the brittle character of Mg2Ca, Al2Ca, and Al4Ca crystalline alloys, proves the superiority of the glassy form for the implant's functioning. The minimum enthalpy of formation and thermodynamic stability of studied compounds benefit the synthesis process; hence, we propose that the studied glasses are persuasive materials for experimental synthesis aimed at bone grating applications. [ABSTRACT FROM AUTHOR]

The boson peak (BP), a low-energy excess in the vibrational density of states over the Debye contribution, is often identified as a characteristic of amorphous solid materials. Despite decades of efforts, its microscopic origin still remains a mystery. Recently, it has been proposed, and corroborated with simulations, that the BP might stem from intrinsic localized modes involving one-dimensional (1D) string-like excitations ("stringlets"). We build on a theory originally proposed by Lund that describes the localized modes as 1D vibrating strings, but we specify the stringlet size distribution to be exponential, as observed in simulations. We provide an analytical prediction for the BP frequency ωBP in the temperature regime well below the observed glass transition temperature Tg. The prediction involves no free parameters and accords quantitatively with prior simulation observations in 2D and 3D model glasses based on inverse power law potentials. The comparison of the string model to observations is more uncertain when compared to simulations of an Al–Sm metallic glass material at temperatures well above Tg. Nonetheless, our stringlet model of the BP naturally reproduces the softening of the BP frequency upon heating and offers an analytical explanation for the experimentally observed scaling with the shear modulus in the glass state and changes in this scaling in simulations of glass-forming liquids. Finally, the theoretical analysis highlights the existence of a strong damping for the stringlet modes above Tg, which leads to a large low-frequency contribution to the 3D vibrational density of states, observed in both experiments and simulations. [ABSTRACT FROM AUTHOR]

Recent methods allow novel amorphous alloy compositions to be rapidly manufactured at small scale; however, obtaining materials properties such as compressive ductility from these smaller specimens has remained a challenge. Here, we suggest a potential high-throughput nanoindentation method that may be able to rapidly characterize the relative compressive ductility between these alloys based on their serration characteristics. The properties of emergent serrations, when interpreted in a simple micromechanical stress relaxation model, may order these materials by their compressive plastic strain to failure. These results are consistent with the ordering obtained from compressed specimens as well as with model simulations, suggesting that this model may be broadly useful for interpreting compressive ductility from nanoindentation serrations. After it is validated on more materials, this new method will match the rapid pace of amorphous alloy development, thus allowing metallic glass properties to be fine-tuned for each application prior to scale prototyping. [ABSTRACT FROM AUTHOR]

Metallic glasses (MGs) are of high strength but limited plasticity at room temperature (RT) due to localized shear in the intrinsically heterogeneous structure. Here, we investigate the variation of structural heterogeneity and plasticity of a Zr-based MG after high-temperature (T) tension under different stresses (σ) at 579 K (0.9Tg, where Tg is the glass transition temperature). The correlation length (ξ) of the heterogeneous structure and the average Young's modulus ( E ¯ ) increase with σ when σ is below 160 MPa; when σ exceeds 160 MPa, both ξ and E ¯ decrease with σ, leading to the improvement of the plasticity. This research could be enlightening for improving the plasticity of MGs at RT through tuning their structural heterogeneity with high-T deformation. [ABSTRACT FROM AUTHOR]

The design of metallic glasses (MGs) with good properties is one of the long-standing bottlenecks in materials science and engineering, which has been relying mostly on far less efficient traditional trial-and-error methods. Even the currently popular machine learning-based forward designs, which use manual input to navigate high dimensional compositional space, often become inefficient with the increasing compositional complexity in MGs. Here, we developed an inverse design machine learning model, leveraging the variational autoencoder (VAE), to directly generate the MGs with good glass-forming ability (GFA). We demonstrate that our VAE with the property prediction model is not only an expressive generative model but also able to do accurate property prediction. Our model allows us to automatically generate novel MG compositions by performing simple operations in the latent space. After randomly generating 3000MG compositions using the model, a detailed analysis of four typical metallic alloys shows that unreported MG compositions with better glass-forming ability can be predicted. Moreover, our model facilitates the use of powerful optimization algorithms to efficiently guide the search for MGs with good GFA in the latent space. We believe that this is an efficient way to discover MGs with excellent properties. [ABSTRACT FROM AUTHOR]

The phenomenon of exchange bias has been extensively studied within crystalline materials, encompassing a broad spectrum from nanoparticles to thin-film systems. Nonetheless, exchange bias in amorphous alloys has remained a relatively unexplored domain, primarily owing to their inherently uniform disordered atomic structure and lacking grain boundaries. In this study, we present a unique instance of exchange bias observed in Fe–B–Nb amorphous thin films, offering insights into its origins intertwined with the system's spin-glass-like behavior at lower temperatures. The quantification of exchange bias was accomplished through a meticulous analysis of magnetic reversal behaviors in the liquid-helium temperature range, employing a zero-field cooling approach from various initial remanent magnetization states (±MR). At reduced temperatures, the appearance of asymmetric hysteresis, a hallmark of negative exchange bias, undergoes a transformation into symmetric hysteresis loops at elevated temperatures, underscoring the intimate connection between exchange-bias and dynamic magnetic states. Further investigations into the magnetic thermal evolution under varying probe fields reveal the system's transition into a spin-glass-like state at low temperatures. We attribute the origin of this unconventional exchange bias to the intricate exchange interactions within the spin-glass-like regions that manifest at the interfaces among highly disordered Fe-nuclei. The formation of Fe-nuclei agglomerates at the sub-nanometer scale is attributed to the alloy's limited glass-forming ability and the nature of the thin-film fabrication process. We propose that this distinctive form of exchange bias represents a novel characteristic of amorphous thin films. [ABSTRACT FROM AUTHOR]

Chemical-ordering in metallic liquid alloys affects important structural, thermodynamic, and dynamical factors governing the kinetics of the glass formation process and the glass-forming ability. The present study on Zr50Cu50, Zr50Cu45Al5, and Zr50Cu45Ag5 metallic glass-forming liquids reveal that minor addition of Al/Ag in Zr50Cu50 leads to different chemical short-range orders due to the hetero-coordination tendency of Al in Zr50Cu45Al5 and homo-coordination tendency of Ag in Zr50Cu45Ag5. Different chemical short-range ordering causes qualitatively different topological short-range orders in the two ternary alloys. Results of inherent structure energy and excess entropy indicate modification of the potential energy landscape such that the local minima (metabasins) on the landscape of Zr50Cu45Al5 become deeper and less rugged, whereas the metabasins become shallower and more rugged in Zr50Cu45Ag5. Single-particle dynamics investigations clearly demonstrate the effect of difference in the chemical-ordering, topological short-range order, and the potential energy landscape on the atomic diffusion, structural relaxation, and dynamic heterogeneities in the ternary alloys. It signifies that the dynamics of the studied glass-forming alloys is closely linked with the structure and thermodynamics. The study also provides a very useful insight of the correlation between the chemical-ordering and the short-time dynamical features in the studied metallic glass-forming liquids. [ABSTRACT FROM AUTHOR]

Glass-forming liquids exhibit long-lived, spatially correlated dynamical heterogeneity, in which some nm-scale regions in the fluid relax more slowly than others. In the nanoscale vicinity of an interface, glass-formers also exhibit the emergence of massive interfacial gradients in glass transition temperature Tg and relaxation time τ. Both of these forms of heterogeneity have a major impact on material properties. Nevertheless, their interplay has remained poorly understood. Here, we employ molecular dynamics simulations of polymer thin films in the isoconfigurational ensemble in order to probe how bulk dynamic heterogeneity alters and is altered by the large gradient in dynamics at the surface of a glass-forming liquid. Results indicate that the τ spectrum at the surface is broader than in the bulk despite being shifted to shorter times, and yet it is less spatially correlated. This is distinct from the bulk, where the τ distribution becomes broader and more spatially organized as the mean τ increases. We also find that surface gradients in slow dynamics extend further into the film than those in fast dynamics—a result with implications for how distinct properties are perturbed near an interface. None of these features track locally with changes in the heterogeneity of caging scale, emphasizing the local disconnect between these quantities near interfaces. These results are at odds with conceptions of the surface as reflecting simply a higher "rheological temperature" than the bulk, instead pointing to a complex interplay between bulk dynamic heterogeneity and spatially organized dynamical gradients at interfaces in glass-forming liquids. [ABSTRACT FROM AUTHOR]

Ovonic threshold switching (OTS) selectors play a critical role in suppressing the sneak-path current of three-dimensional crossbar integration circuits. Compared to conventional nonmetal-telluride OTS selectors, selectors based on AlxTey glass are found to have both satisfactory on-state current and selectivity. However, it is unclear why the Al-rich AlxTey glass-based OTS selectors have robust insulation properties for reducing the off-state current. This work reveals the structure–property correlations of amorphous AlxTey at the atomic scale by first-principles calculations. It is found that the stoichiometric Al2Te3 glass tends to have a clean bandgap owing to the covalent and dative bonds formed by non-equivalent sp3-hybridized Al orbitals and the lone-pair electrons of Te. Unexpectedly, for Al-rich AlxTey glass (Al2.21Te2.79), the Al–Al bonds formed by redundant Al-atoms have an integrated crystal orbital bond index (ICOBI) of 0.8–0.9, which is much larger than that of Al–Al bonds in pure metals (0.227), indicating they are covalent. It is the covalent Al–Al bonds that ensure the robust insulation characteristics of Al-rich AlxTey glass, while the Te–Te interaction in the Al-poor AlxTey glass (Al1.79Te3.21) produces midgap states, thereby reducing the insulativity. The presented atomic and electronic pictures here will provide useful theoretical insights for designing OTS selectors with improved performances. [ABSTRACT FROM AUTHOR]

The thermophysical properties of liquid metals and alloys are crucial to explore the intrinsic mechanisms of the solidification process, glass formation, and fluid dynamics. The deep learning approaches have emerged as powerful tools in numerous scientific fields and exhibit extraordinary accuracy in the estimation of physical properties and structural characteristics for various materials. In this Tutorial, focusing on the thermophysical properties of liquid multicomponent alloys, deep learning methods, including both supervised learning and active learning, are introduced. Combined with the verification from electrostatic and electromagnetic levitation experiments, the influences of training parameters and methods on the accuracy to obtain interatomic potential by deep learning are revealed on the basis of deep neural network algorithm. As a result, this prediction method of liquid state properties for multicomponent alloys exhibited the dual advantages of high accuracy derived from density functional theory and low computational cost associated with empirical potential. [ABSTRACT FROM AUTHOR]

We study the thermodynamic behavior of sodium perchlorate solutions in supercooled water through molecular dynamics numerical simulations. These solutions are of special interest because of the recent experimental results that led to hypothesize the presence of liquid water in perchlorate solutions beneath the Martian soil. We model water using the TIP4P/2005 potential. The results we obtain for solutions with concentrations 1.63 and 15.4 wt% are in agreement with those of a system undergoing a liquid–liquid phase transition where the liquid–liquid critical point shifts to slightly higher temperatures and lower pressures. The structure of the system is also analyzed, and we come to the conclusion that, even at the highest concentration considered, water retains its anomalous behavior. [ABSTRACT FROM AUTHOR]

Sluggish kinetics of oxygen evolution reaction (OER) is the main factor limiting the efficiency of water electrolysis. Heteroatom doping, interface engineering and compositing with conductive substrate are promising strategies to construct highly efficient electrocatalysts. Herein, several Zr and Fe co-doped crystalline cobalt with surface amorphous oxide layer wrapped in one-dimensional N-doped carbon fibers composite electrocatalysts have been prepared by pyrolyzing the electrospinning precursors in N 2 at 800 °C and followed by oxidizing in air at 200 °C. Mainly due to modulation of electron structure by Zr and Fe dopant and the interfacial effect of crystalline/amorphous heterostructure, the as-prepared catalysts exhibited excellent OER performances. As a result, only 374 mV of overpotential was needed for the optimized ZFCO@Co/CN-0.3:0.4:2.0 catalyst to reach 20 mA m- of current density. This work provides a new avenue for rational design of composite electrocatalysts for water splitting. Zr and Fe co-regulated cobalt-based one-dimensional composite fiber nanomaterials as highly efficient electrocatalysts for OER. Thanks to the heterogeneous structure, synergistic effect and one-dimensional fiber nanostructure, the prepared catalysts showed excellent OER catalytic activity and stability in alkaline media. [Display omitted] • Zr and Fe co-regulated cobalt wrapped in N-doped carbon fibers were prepared. • The surfaces of the metals were oxidized to form amorphous oxides layer. • Interfacial effect was exhibited in the crystalline/amorphous heterostructure. • Highly synergistic effect was exhibited among the multiple components. • The optimized catalyst exhibited superior OER electrocatalytic activity than RuO 2. [ABSTRACT FROM AUTHOR]

Low stability deriving from the accumulation of moisture and intermediates represents the major challenge for practical applications of manganese oxides (MnO x) for ozone elimination. Here, Li+, Na+ and K+ were successfully introduced into the channel framework of amorphous MnO x to improve its stability through a simple post-treatment method. Alkali metal modification can promote the removal of ozone by amorphous MnO x , and Na-MnO x exhibited superior catalytic activity and remarkable stability in water-resistance, cycling and long-term tests. The Na introduction facilitated the formation of oxygen vacancies, and improved low-temperature reducibility and lattice oxygen mobility. The mechanism of ozone decomposition on amorphous MnO x and Na-MnO x catalysts was deeply investigated by in situ diffuse reflectance infrared Fourier transform spectra (in-situ DRIFTS). The Na addition strengthened the hydrophobicity of oxygen vacancies, but also greatly boosted the desorption of intermediate oxygen species and the ozone decomposition cycle. [Display omitted] [ABSTRACT FROM AUTHOR]

ABSTRACT This study presents the development of a small electric vehicle (EV) traction drive motor using Fe‐based amorphous laminated cores that can be mass produced. The following innovative technologies are developed to realize the amorphous laminated core: (1) production technology for thicker amorphous alloy foils to reduce the number of machining operations and (2) punching press technology for amorphous alloy foils that improves the usability of the tool life and maintains quality. The interior permanent magnet synchronous motor (IPMSM) using the amorphous laminated core is designed to be compatible with a 4.5‐kW‐class small EV traction drive with high efficiency while satisfying the required torque characteristics. A prototype of the designed IPMSM was manufactured and evaluated. The test machine achieves a maximum efficiency of 98.7% and a wide range of efficiencies exceeding 97%. Additionally, the prototype motor exhibit improved efficiency in all operating points compared with a prototype manufactured using an electrical steel sheet. [ABSTRACT FROM AUTHOR]

Borophosphate-based glass materials have the potential to revolutionize optical technology because of their outstanding optical properties, long-lasting nature, and cost-effectiveness. The present research addresses the intricate functions of rare earth and metallic nanoparticles (NPs) in borophosphate glass, which have significant potential for optical photonic and medical applications by incorporating Dy3+ ions and Cu NPs. We developed novel hybrid glasses through the melt-quenching technique, which includes the creation of functional groups and the establishment of bonds between P2O5 and B2O3, as confirmed by FTIR and Raman spectroscopy. UV–visible absorption spectra were used to identify the presence of Cu⁺ and Cu (Saeed et al., 2021) [2]⁺ ions and Cu nanoparticles, with the absorption peaks indicating their respective states. Furthermore, the underlying mechanisms of energy transfer in a glass matrix that is co-doped with dysprosium ions (Dy3+) have been studied. The experimental findings of this research not only provide valuable information about the physical properties of borophosphate glass but also emphasize the collaborative relationship between the rare-earth ion and copper nano-powders. The Tauc plot analysis demonstrated a correlation between the concentration of Cu and Dy dopants and a decrease in the energy band gap of the glass. This suggests that these dopants influence the electronic structure of the glass. This study opens up possibilities for creating innovative photonic materials with customized optical attributes. [Display omitted] [ABSTRACT FROM AUTHOR]

This document provides a comprehensive list of upcoming conferences and events in the field of X-ray spectrometry and other scientific disciplines. These conferences will be held in various countries around the world, including the United States, Japan, Taiwan, Brazil, Germany, Australia, Belgium, and Malaysia, among others. The topics covered in these conferences are diverse and include X-ray chemical analysis, electron tomography, nanotechnology, and neutron scattering, among others. The document also includes links to the official websites of each conference for more detailed information. [Extracted from the article]

Magnetoelectric (ME) sensors have enormous potential for detecting weak magnetic fields because of their high sensitivity, low power consumption, compact size and, low cost. However, inevitable vibration interference limits their application in practical environments, especially in the case of mobile platform mounting. Here, we propose a differential ME sensor, consisting of PZT macro-fiber composites (MFCs) and Metglas laminates. The differential ME sensor has two output terminals with weak mutual mechanical coupling and works in longitudinal vibration mode. MFC cores are polarized in parallel mode to guarantee their consistency of electric characteristics and reversed bias field is provided by attached magnets. Experimental results show that the differential-mode response amplitudes have a gain of −17.6 dB for low-frequency vibration at 2 Hz and ∼6.2 dB for an applied magnetic field at 3 Hz, in comparison with the single-ended mode. In addition, our proposed ME sensor also has a low inherent equivalent magnetic noise of 18.3 pT/√Hz at 1 Hz. Finally, a target detection experiment in the presence of heavy lab noise and strong vibration interference is conducted and the improved detection performance of the proposed differential ME sensor is proved. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting, including the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), is a promising hydrogen production technology. However, in practice, the high overpotentials and sluggish reaction kinetics associated with the anode OER process are the major obstacles to the smooth progress of electrocatalytic water splitting. Amorphous electrocatalysts, a crucial family of functional materials, exhibit unexpected performance due to their special short‐range ordered and long‐range disordered atom arrangement, abundant defect sites and adjustable composition. To date, while numerous recent publications showcase promising results for transition metal‐based amorphous electrocatalysts, including amorphous metal phosphide and metal hydroxide electrocatalysts with remarkable HER and OER properties respectively, the utilization of single‐function HER or OER catalysts tends to augment system complexity for water electrolysis, thereby escalating the cost of hydrogen production. In this regard, amorphous HER/OER bifunctional electrocatalysts are desired. In this review, we summarize the recent development on transition metal‐based amorphous catalysts for electrochemical water splitting. The design strategies for constructing HER/OER bifunctional transition‐metal‐based amorphous electrocatalysts are highlighted here, also including the exploration of relationship between catalyst structures and their remarkably improved performance. Finally, the possibilities of amorphous bifunctional catalysts for practical industrial applications are evaluated and future research direction are suggested. [ABSTRACT FROM AUTHOR]

Metallic glass fibers have high strength, poor plasticity and low Young's modulus. In this study, it was used as a reinforcement to prepare metallic glass fiber reinforced epoxy composites with different fiber volume contents (20%, 30%, 40%, and 50%). The effect of fiber volume contents on the tensile properties of the metallic glass fiber reinforced epoxy composites was studied by experiment and the finite element analysis method. The experiment and simulation results are in good agreement. The tensile strength and plasticity of the metallic glass fiber reinforced epoxy composites increase with the increase of fiber volume contents. When the fiber volume content is 40% or 50%, a sharply necking feature appeared on the fibers and exhibited improved plasticity, due to the formation of interacting and arresting events of shear bands occurring at the interface between the metallic glass fibers and the epoxy. In addition, the strain hardening due to plastic deformation of the metallic glass fibers further enhanced the tensile strength of the metallic glass fiber reinforced epoxy composites. This is a first step toward toughening the inherently brittle metallic glass fibers under tensile conditions. Highlights: A novel CoFeSiB metallic glass fiber reinforced epoxy resin compositeThe increase of fiber volume fraction improves the tensile strength and plasticity of fiber reinforced composites.The strain hardening due to plastic deformation of the metallic glass fibers further enhanced the tensile strength of the metallic glass fiber reinforced epoxy composites. [ABSTRACT FROM AUTHOR]

The slow kinetics of four-electron-transfer oxygen evolution reaction (OER) highly impedes the conversion efficiency of overall water splitting for green hydrogen production. Recently, metal-organic frameworks (MOFs) have attracted widespread attention due to their tunable morphologies, well-defined structures, and abundant metal sites. In this work, a series of cobalt-incorporated NiFe-MOF nanosheets were in-situ synthesized on nickel foam. Owing to the synergistic effect of exposed multi-metal sites, NiFeCo-BDC exhibits excellent OER activity, delivering an ultralow overpotential of 233 mV at the current density of 10 mA cm−2 with a small Tafel slope of 40.8 mV dec−1. In the continuous chronoamperometry test at 100 mA cm−2, almost no potential attenuation can be found over 200 h, demonstrating its remarkable stability. After OER, the amorphous metal oxyhydroxide layer is generated on surface, and the high-valent species are responsible for the superior OER performance. In-situ Raman spectra reveal that the organic ligands of NiFe-BDC and NiFeCo-BDC are etched and released during OER, and the Co incorporation facilitates the generation of amorphous layer. This work presents an effective strategy for design of multi-metal MOF-based electrocatalysts, and provides an insightful view on the structure evolution during OER. [Display omitted] • Construction of self-supported trimetallic NiFeCo-BDC nanoarrays. • Superior OER performance with ultra-low overpotential and excellent stability. • In-situ Raman studies on deciphering the self-reconstruction process. [ABSTRACT FROM AUTHOR]

The Zr37Hf16Ni12.5Cu12.5Al11Co6Nb5 bulk metallic glass (BMG) with strong glass-forming ability (GFA) and remarkable mechanical properties was designed, and its thermophysical properties were characterized simultaneously. The glass transition temperature reached up to 726 K, while the fragility index of 43 was derived by measuring alloy viscosity. The undercooled liquid of this BMG with such a low fragility index displayed a strong liquid behavior, corresponding to its small crystallization driving force and high GFA. The thermal expansion coefficient increased from 9.76 × 10−6 K−1 of glassy state to 2.71 × 10−5 K−1 of undercooled liquid, and the close-packed structure was evidenced by the low specific energy for free volume formation of 239.4 kJ/mol. Owing to its low free volume and high glass transition temperature, this BMG exhibited remarkable tensile and compressive yield strengths up to 1660.3 and 2042.3 MPa, respectively. [ABSTRACT FROM AUTHOR]

Blister-based laser-induced forward transfer (BB-LIFT) is a promising high precision and resolution printing technique for the fast, solvent- and mask-free transfer of functional layered materials onto micro-devices. It utilizes a protective metal (blister) layer sandwiched between the laser-transparent substrate and the material to be transferred. The metal layer absorbs the incident laser pulse, creating a rapidly expanding blister that propels the overlying material onto a target substrate. We show that BB-LIFT of thin and ultrathin (30 and 3 nm) ZrO2 films is realized only with a "graphene release layer" applied between the Al blister layer and the ZrO2 donor layer. Without such intercalation, ZrO2 is inseparable from the blister layer due to the strong oxide bonding with aluminum oxides formed during the preparation. The ZrO2 transfer was confirmed through high-resolution scanning electron microscopy and energy-dispersive X-ray spectroscopy, affirming the critical role of graphene as a release layer. The promotion of mechanically strong, flexible graphene as a release layer can be generalized in BB-LIFT applications if thin films of fragile, polycrystalline, or amorphous metal oxides must be printed for gas sensors, catalytic, or other applications. [ABSTRACT FROM AUTHOR]

Developing high‐efficiency durable electrocatalysts in wide pH range for water splitting is significant for environmentally‐friendly synthesis of renewable hydrogen energy. Herein, a facile method by dealloying designable multicomponent metallic glass precursors is reported to synthesize amorphous‐crystalline heterostructured nanoporous high‐entropy alloys (AC‐HEAs) of CuAgAuPtPd, CuAgAuIrRu, and CuAgAuPtPdIrRu, heaped up by nanocrystalline particles with an average size of 2‐3 nm and the amorphous glued phase. The synthesized AC‐HEA‐CuAgAuPtPd owns highly catalytic performances for hydrogen evolution reaction (HER), with 9.5 and 20 mV to reach 10 mA·cm−2 in 0.5 m H2SO4 and 1.0 m KOH, and AC‐HEA‐CuAgAuIrRu delivers 208 and 200 mV for oxygen evolution reaction (OER). Moreover, a two‐electrode electrolyzer made of the AC‐HEA‐CuAgAuIrRu bifunctional electrodes exhibit a low cell voltage of 1.48 and 1.49 V in the acidic and alkaline conditions at 10 mA·cm−2 for overall water splitting. Combining the enhanced catalytic activities from nanoscale amorphous structure and atom‐level synergistic catalyst in AC‐HEAs provides an effective pathway for pH‐universal electrocatalysts of water splitting. [ABSTRACT FROM AUTHOR]

The global energy market is shifting toward renewable, sustainable, and low-carbon hydrogen energy due to global environmental issues, such as rising carbon dioxide emissions, climate change, and global warming. Currently, a majority of hydrogen demands are achieved by steam methane reforming and other conventional processes, which, again, are very carbon-intensive methods, and the hydrogen produced by them needs to be purified prior to their application. Hence, researchers are continuously endeavoring to develop sustainable and efficient methods for hydrogen generation and purification. Membrane-based gas-separation technologies were proven to be more efficient than conventional technologies. This review explores the transition from conventional separation techniques, such as pressure swing adsorption and cryogenic distillation, to advanced membrane-based technologies with high selectivity and efficiency for hydrogen purification. Major emphasis is placed on various membrane materials and their corresponding membrane performance. First, we discuss various metal membranes, including dense, alloyed, and amorphous metal membranes, which exhibit high hydrogen solubility and selectivity. Further, various inorganic membranes, such as zeolites, silica, and CMSMs, are also discussed. Major emphasis is placed on the development of polymeric materials and membranes for the selective separation of hydrogen from CH4, CO2, and N2. In addition, cutting-edge mixed-matrix membranes are also delineated, which involve the incorporation of inorganic fillers to improve performance. This review provides a comprehensive overview of advancements in gas-separation membranes and membrane materials in terms of hydrogen selectivity, permeability, and durability in practical applications. By analyzing various conventional and advanced technologies, this review provides a comprehensive material perspective on hydrogen separation membranes, thereby endorsing hydrogen energy for a sustainable future. [ABSTRACT FROM AUTHOR]

It is imperative to enhance the mechanical properties and corrosion resistance of magnesium (Mg)-based metallic glasses for orthopedic implants to further their development. The addition of yttrium (Y) significantly improves both of these characteristics. The Mg52.5Zn40.5Ca5Y2 alloy was chosen for its optimal glass-forming capabilities, as evidenced by thermodynamic parameter, PHHS. This alloy demonstrates remarkable enhancements in both mechanical and corrosion properties, despite the presence of a stable Mg12YZn phase in the liquid, which precludes the complete formation of glass. The Mg52.5Zn40.5Ca5Y2 alloy exhibits a substantial increase in hardness, surpassing the Mg66Zn30Ca4 metallic glass by up to 30 HV. The compressive strength of this alloy is 690 MPa, which is approximately 138 MPa greater than that of the Mg66Zn30Ca4 alloy. The Mg52.5Zn40.5Ca5Y2 alloy exhibits a higher noble corrosion potential and a lower corrosion current density demonstrating a corrosion current density of 6.970 µA/cm2 and a corrosion potential of − 1.240 V. These values suggest a significant increase in corrosion resistance when contrasted with the baseline alloy, Mg66Zn30Ca4. The primary cause of this improvement in mechanical behavior and corrosion resistance is the formation of Mg12YZn long-period stacking ordered (LPSO) phases and Mg3YZn6 icosahedral phases. The material's overall strength and durability are enhanced by these phases, rendering it a promising candidate for applications that necessitate high performance in both mechanical and corrosive environments. As per the results, Mg52.5Zn40.5Ca5Y2 alloy is an exceptional choice for advanced material applications due to its distinctive phase composition, which results in superior properties. [ABSTRACT FROM AUTHOR]

Stainless steels 316 and 304 are among the alloys commonly used to make medical equipment, including surgical instruments. These steels, however, do not exhibit properties that control bacterial growth or destroy bacteria upon contact, leading to significant contamination. This problem can be largely mitigated by applying coatings with high antibacterial properties. One such coating that has attracted considerable attention from researchers, in recent years, is Zr-based metallic glass coatings. In this study, after studying the effects of different elements on the antibacterial behavior of coatings, an alloy with the chemical composition of Zr30Cu20Al10Ag10Cr10Si10B10 was designed and produced. A thin layer of this amorphous alloy was then applied to a 316 stainless steel substrate, and its behavior against two common hospital bacteria was studied. After weighing and mixing the selected elements in the required stoichiometric ratios and homogenizing them using a mechanical ball mill, a target with the desired chemical composition was produced using Spark Plasma Sintering (SPS). Structural investigations revealed a uniform distribution of the elements in the produced target. Using this target, thin layers of the alloy with different thicknesses were deposited on the 316 stainless steel substrate. Preliminary investigations showed that the coatings, in addition to forming a good bond with the substrate, possess a glassy and amorphous structure. The antibacterial behavior of the coatings against Escherichia Coli and Staphylococcus Aureus was then investigated. The results showed that the coatings, due to the presence of copper and silver, exhibit high antibacterial properties against these bacteria. Furthermore, the application of the coating, which reduces the roughness of the polished 316 substrate by 50%, can significantly affect the adhesion of human and animal blood platelets, as well as human and animal cancer cells, to surgical instruments made from 316 stainless steel. [ABSTRACT FROM AUTHOR]

Blister-based laser-induced forward transfer (BB-LIFT) is a promising high precision and resolution printing technique for the fast, solvent- and mask-free transfer of functional layered materials onto micro-devices. It utilizes a protective metal (blister) layer sandwiched between the laser-transparent substrate and the material to be transferred. The metal layer absorbs the incident laser pulse, creating a rapidly expanding blister that propels the overlying material onto a target substrate. We show that BB-LIFT of thin and ultrathin (30 and 3 nm) ZrO2 films is realized only with a "graphene release layer" applied between the Al blister layer and the ZrO2 donor layer. Without such intercalation, ZrO2 is inseparable from the blister layer due to the strong oxide bonding with aluminum oxides formed during the preparation. The ZrO2 transfer was confirmed through high-resolution scanning electron microscopy and energy-dispersive X-ray spectroscopy, affirming the critical role of graphene as a release layer. The promotion of mechanically strong, flexible graphene as a release layer can be generalized in BB-LIFT applications if thin films of fragile, polycrystalline, or amorphous metal oxides must be printed for gas sensors, catalytic, or other applications. [ABSTRACT FROM AUTHOR]

This study delves into subtle changes in the microstructure and domain arrangement of a Fe74B20Nb2Hf2Si2 soft magnetic amorphous alloy. Utilizing transmission electron microscopy in Lorentz mode, low-magnification STEM, and differential phase contrast analysis (DPC), the research explores both the as-cast state and annealed samples. The results confirmed the formation of α-Fe, Fe23B6, Fe2(Hf, Nb), and Fe2B crystalline phases with increasing annealing temperature. Consequently, these crystallization stages induce significant alterations in magnetic domain size and spatial distribution due to microstructural changes. As the crystallization temperature rises, the volume fraction of crystalline phases increases, leading to modifications in the arrangement and size of magnetic domains. The decrease in magnetic domain size, associated with the formation of pinning sites during heat treatment, leads to alterations in soft magnetic properties. This includes an increase in coercivity (Hc) up to 40 A/m in the sample annealed at the temperature range of the third crystallization stage compared to the as-cast sample (1.5 A/m). Furthermore, as the annealing temperature rises, there is a corresponding increase in saturation magnetization (Ms), which reached to 1.71 T in the sample annealed within the temperature range of the third crystallization stage. These findings hold substantial implications for the practical applications of the Fe-based soft bulk metallic glasses (BMGs) alloy across various industries. [ABSTRACT FROM AUTHOR]

Metallic glasses are non-crystalline solids which form when crystal nucleation and growth is precluded either fully or partly. In the event of a partial suppression of crystal formation, a solid result which has crystals embedded in an amorphous glassy matrix. The process of solidification can be studied in a unique way from the liquid side by examining this composite. The effect of subtle changes in the liquid structure on the formation of crystals is possible to study by this methodology, something which is impossible otherwise. This presentation first examines the effect of liquid structure on the nucleation of crystals by examining the short-range order in the glass. The stability of the liquid/crystal interface and growth of crystals by addition of atomic ledges have been examined. The structure of the liquid also get effected by the cooling rates. How these changes in the structure of the liquid due to cooling rate variation is manifested in the change of the medium-range order (MRO) as a function of cooling rate and the consequent effect on properties. Finally, the changes taking place in a liquid just before it transforms to crystal are ascertained by examining the MRO of supercooled liquid just next to the liquid/crystal interface and that away from the interface. [ABSTRACT FROM AUTHOR]

This study presents a molecular dynamics (MD) investigation of the evolution of local atomic environments (LAEs) in a Cu66Zr34 bulk metallic glass (BMG), both at rest and under constant shear deformation. LAEs were characterized using Voronoi polyhedra analysis. Even in the absence of external load, LAEs frequently transformed into one another due to short-ranged atomic position fluctuations. However, as expected, each transition from one polyhedra to another was balanced by the reverse transition, thereby preserving the proportions of the different polyhedra. Cu-centered icosahedral LAEs were observed to preferentially transform into and from <1,0,9,3,0>, <0,1,10,2,0>, and <0,2,8,2,0> LAEs. Upon applying pure shear, the simulation box was first deformed in one direction up to a strain of 25% and then in the opposite direction to the same strain level. Shear deformation induced large nonaffine atomic displacements in the directions parallel to the shear, which were concentrated in specific regions of the BMG, forming band-like regions. From the onset, shear deformation led to the destabilization of Cu-centered icosahedral LAEs, as indicated by more frequent transitions to and from other polyhedra. Unlike other Cu-centered LAEs, icosahedra were also found to be more sensitive to yielding. The destruction of Cu-centered icosahedra was primarily a result of net transformations into <1,0,9,3,0> and <0,2,8,2,0> LAEs in the BMG subjected to pure shear, with a minor contribution of transformations involving the <0,1,10,2,0> polyhedra. [ABSTRACT FROM AUTHOR]

The growing importance of submicrometer‐structured surfaces across a variety of different fields has driven progress in light manipulation, color diversity, water‐repellency, and functional enhancements. To enable mass production, processes like hot‐embossing (HE), roll‐to‐roll replication (R2R), and injection molding (IM) are essential due to their precision and material flexibility. However, these processes are tool‐based manufacturing (TBM) techniques requiring metal molds, which are time‐consuming and expensive to manufacture, as they mostly rely on galvanoforming using templates made via precision microlithography or two‐photon‐polymerization (2PP). In this work, a novel approach is demonstrated to replicate amorphous metals from fused silica glass, derived from additive manufacturing and structured using hot embossing and casting, enabling the fabrication of metal insets with features in the range of 300 nm and a surface roughness of below 10 nm. By partially crystallizing the amorphous metal, during the replication process, the insets gain a high hardness of up to 800 HV. The metal molds are successfully used in polymer injection molding using different polymers including polystyrene (PS) and polyethylene (PE) as well as glass nanocomposites. This work is of significant importance to the field as it provides a production method for the increasing demand for sub‐micron‐structured tooling in the area of polymer replication while substantially reducing their cost of production. [ABSTRACT FROM AUTHOR]

This article reviews the research and development focus of metallic glasses in the field of biomedical applications. Metallic glasses exhibit a short-range ordered and long-range disordered glassy structure at the microscopic level, devoid of structural defects such as dislocations and grain boundaries. Therefore, they possess advantages such as high strength, toughness, and corrosion resistance, combining characteristics of both metals and glasses. This novel alloy system has found applications in the field of biomedical materials due to its excellent comprehensive performance. This review discusses the applications of Ti-based bulk metallic glasses in load-bearing implants such as bone plates and screws for long-term implantation. On the other hand, Mg-based metallic glasses, owing to their degradability, are primarily used in degradable bone nails, plates, and vascular stents. However, metallic glasses as biomaterials still face certain challenges. The Young's modulus value of Ti-based metallic glasses is higher than that of human bones, leading to stress-shielding effects. Meanwhile, Mg-based metallic glasses degrade too quickly, resulting in the premature loss of mechanical properties and the formation of numerous bubbles, which hinder tissue healing. To address these issues, we propose the following development directions: (1) Introducing porous structures into titanium-based metallic glasses is an important research direction for reducing Young's modulus; (2) To enhance the bioactivity of implant material surfaces, the surface modification of titanium-based metallic glasses is essential. (3) Developing antibacterial coatings and incorporating antibacterial metal elements into the alloys is essential to maintain the long-term effective antibacterial properties of metallic biomaterials. (4) Corrosion resistance must be further improved through the preparation of composite materials, while ensuring biocompatibility and safety, to achieve controllable degradation rates and degradation modes. [ABSTRACT FROM AUTHOR]

Ti-based bulk metallic glass composites (BMGMCs) containing an in situ formed metastable β phase normally exhibit enhanced plasticity attributed to induced phase transformation or twinning. However, the underlying deformation micromechanism remains controversial. This study investigates a novel deformation mechanism of Ti-based BMGMCs with a composition of Ti42.3Zr28Cu8.3Nb4.7Ni1.7Be15 (at%). The microstructures after tension were analyzed using advanced electron microscopy. The dendrites were homogeneously distributed in the glassy matrix with a volume fraction of 55 ± 2% and a size of 1~5 μm. The BMGMCs deformed in a serrated manner with a fracture strength (σf) of ~1710 MPa and a fracture strain of ~7.1%, accompanying strain hardening. The plastic deformation beyond yielding was achieved by a synergistic action, which includes shear banding, localized amorphization and a localized BCC (β-Ti) to HCP (α-Ti) structural transition. The localized amorphization was caused by high local strain rates during shear band extension from the amorphous matrix to the crystalline reinforcements. The localized structural transition from BCC to HCP resulted from accumulating concentrated stress during deformation. The synergistic action enriches our understanding of the deformation mechanism of Ti-based BMGMCs and also sheds light on material design and performance improvement. [ABSTRACT FROM AUTHOR]

Chemical and topological short-range ordering are important for glass formation in metallic alloys. Yet, it remains little understood from the viewpoint of the electronic bonding among the constituent elements of the alloys. In this work, we study CuxZr100−x, (46 ≤ x ≤ 70) metallic glasses, where the atomic packing efficiency and the electronic structure of the full icosahedra, the key short-range order structures, have been investigated in detail. To capture a realistic picture of the electronic bonding in the icosahedra in the as-quenched metastable state, DFT study of the electronic structure of the icosahedra extracted from classical molecular dynamics simulation is carried out. Results for the CunZr13−n, (4 ≤ n ≤ 9) clusters reveal that Cu6Zr7, Cu7Zr6 and Cu8Zr5 are the most abundant, electronically stable in Cu50Zr50, Cu58Zr42 and Cu64Zr36, respectively. These three clusters also exhibit pseudo-gap in the density of states at the Fermi level – a feature linked with glass-forming ability according to the nearly-free electron approach. The partial density of states demonstrates the effect of small changes in the stoichiometry of the clusters on the s, p and d states of Cu and Zr in Cu–Cu and Cu–Zr bonding and hence, the stability of the clusters. [ABSTRACT FROM AUTHOR]

Chondrules and Ca-Al-rich inclusions (CAIs) have been considered characteristic constituents of chondritic meteorites, although the outward transportation of CAIs has been theoretically pointed out. Stardust samples recovered by the Stardust mission from the 81P/Wild2 comet contained chondrule-like objects (CLOs) and refractory inclusions that include CAIs and amoeboid olivine aggregates (AOAs). However, it was not proven that the CLOs, AOAs, and CAIs coexist with fine-grained materials equivalent to chondritic porous interplanetary dust particles (CP IDPs) containing abundant glass with embedded metal and sulfides (GEMS). Here we report on two type II CLOs, containing <90 Mg# in ferromagnesian silicates, enclosed in GEMS-rich CP Antarctic micrometeorites (AMMs) (CP IDPs that reached the surface of the Earth) and one igneous object rich in kosmochloric (Ko-rich: NaCrSi 2 O 6 -rich) high-Ca pyroxene and Fe-bearing olivine (KOOL) that is enclosed in a CP IDP. KOOL grains have also been found in Stardust samples and CP IDPs. These three igneous objects are embedded in fine-grained matrices that do not show any evidence of aqueous alteration. The low Mg# and elevated Δ17O of olivine and pyroxene in these CLOs and the KOOL grain are consistent with previously studied CLOs from comet 81P/Wild 2 and a giant cluster IDP. These results support the view that CP IDP- and CP AMM-like materials constitute samples from comets or comet-like icy bodies. The CLOs were formed in oxidizing environment beyond the snow line and then transferred to the comet-forming region. In contrast, a spinel-hibonite (SHIB) fragment found in an AMM experienced aqueous alteration of its rim. The SHIB fragment contains ultrarefractory oxides and refractory metal nuggets and has a 26Mg excess like typical meteoritic CAIs. The mineralogy of the fine-grained matrix is very similar to CP IDPs and CP AMMs. However, because "GEMS" in the matrix of the SHIB fragment-bearing AMM lacks Fe-Ni metal and amorphous silicate in it contains Fe, it is clear that the matrix weakly experienced aqueous alteration. Olivine / (Olivine + low-Ca pyroxene) ratios in the matrices of the four samples range from 0.4 to 0.6, which are comparable with those of anhydrous CP IDPs and CP MMs (around 0.5), and those of P- and D-type asteroids and Jupiter-family comets (around 0.5). [ABSTRACT FROM AUTHOR]

The exploration of energy harvesting encompasses a wide array of sources, with a specific focus on recovering mechanical and magnetic energy from overlooked outlets, driving current research endeavours. In this study, we developed highly flexible Magneto-Mechano-Electric (MME) harvesters by combining poly(vinylidene fluoride) (PVDF)/barium calcium zirconium titanate (BCT-BZT) composite films with metglas. The flexible piezoelectric polymer-ceramic composite films were fabricated using a solvent casting technique. The high piezoelectric BCT-BZT fillers were synthesized through a sol-gel reaction route. A thorough analysis was carried out on these composites to evaluate their structural, functional, microstructural, and dielectric properties. The composite film loaded with 20 wt% BCT-BZT filler achieved a 78 % β-phase with a significant enhancement in the dielectric properties, resulting in a high permittivity∼40 and low dielectric loss. Employing these films, we engineered nanogenerators capable of converting mechanical energy into electrical energy, yielding an output voltage of 11 V. Thereafter, to harvest mechanical and stray magnetic fields, we developed a MME generator comprising a magnetic Metglas layer and PVDF-BCT-BZT composite and achieved an output voltage of 3.3 V with a power density of 85 μW/m2 when subjected to an AC magnetic field of 5 Oe. Furthermore, the MME generator has demonstrated the ability to charge various capacitors showcasing its potential for usage in self-powered, non-contact, and implantable devices. [ABSTRACT FROM AUTHOR]

The rejuvenation or energy‐storage behavior in metallic glasses (MGs) has been extensively explored for its theoretical and practical significance. However, very limited research focuses on the rejuvenation of high entropy metallic glasses (HEMGs), leaving uncertainties about how configurational entropy influences this process. In this study, cryogenic temperature cycling (CTC) is utilized to unlock the rejuvenation potential of a series of La‐based MGs with different entropy values. Comparative analysis of these MGs reveals that increased entropy boosts the maximum rejuvenation degree from 37% to 65% and widens the range of energy states where rejuvenation occurs. The changed rejuvenation behavior induced by entropy increase, which has never been reported other studies, are related to glass's structures, fragility and coupling degree between β and α relaxations. Besides, a new rejuvenation mechanism is revealed in HEMGs, which differs significantly from unrestricted growth and interconnection of flow units observed in most MGs. The atomic motion in HEMGs is confined within the icosahedral backbone network during CTC. Surprisingly, this local motion can propagate through strong interactions between adjacent atoms, facilitating the activation of α relaxation. These discoveries offer novel approaches to tune energy‐storage behavior of MGs by modulating icosahedral network structures through entropy control. [ABSTRACT FROM AUTHOR]

The CO2 electroreduction reaction using sustainable electricity emerges as a viable strategy to produce high‐value‐added and profitable chemicals. The achievement of superior activity at a lower overpotential and higher selectivity in a wide potential window is vitally important for large‐scale industrial applications. Herein, a carbon‐composite amorphous porous BiSbOx nanotube with abundant unsaturated sites is reported to boost the conversion of CO2 to formate, exhibiting a formate selectivity of >90% in an extremely broad range of potentials from −0.5 to −1.4 V versus reversible hydrogen electrode (RHE) and a maximal energy conversion efficiency of 77.1%. Importantly, pure formic acid solution is directly obtained in a solid‐electrolyte cell for industrial‐scale applications. The porous tubular structure can expose more catalytic active sites, accelerate the mass transfer, and show fast surface charge transfer. Moreover, the unique coordination‐unsaturated Sb‐stabilized BiO8−x site can not only enhance the adsorption and activation of CO2 but also reasonably balance the stabilization and hydrogenation of *OCHO intermediate, thus leading to its obviously higher catalytic performance. As a result, a novel amorphous porous BiSbOx nanotube is successfully designed for efficient CO2 electroreduction, which may shed new light on developing many more amorphous composite metal oxide catalysts for conversion of inert small molecules. [ABSTRACT FROM AUTHOR]

Glass formation and the nature of the chemical interaction in the As2Se3–Tl2Te3 system were studied by differential-thermal (DTA), X-ray phase (XRD), microstructural (MSA) analysis. Based on the performed experiments T-x phase diagram is constructed. It is established that the phase diagram of the system is a partially quasi-binary section of the quaternary system Tl,As//Se,Te. Eutectic equilibrium and peritectic transformation process occur in the system. When the ratio of As2Se3 and Tl2Te3 components is 1:1, a new quaternary compound Tl2As2Se3Te3 is formed. It has been established that the Tl2As2Se3Te3 compound melts with an open maximum at 568 K and crystallizes in a hexagonal symmetry. In the system, under normal cooling, the glass formation area reaches −80 mol.% Tl2Te3, and in the mode of quenching in liquid nitrogen up to −100 mol.% T12Te3. The photoelectric properties of glassy alloys (As2Se 3 ) 1 − x (Tl2Te 3 ) x (x = 0. 0 1 ; 0.3; 0.05) have been studied. Depending on the Tl2Te3 concentration of the system, the observed changes in the photoelectric properties and calculated parameters are presented. [ABSTRACT FROM AUTHOR]

The corrosion behavior of a novel Fe57Cr10Mo5Nb2Zr8B18 metallic glass (MG) and BSS in simulated wet storage environment of spent nuclear fuels at different temperatures was studied comparatively by electrochemical techniques. The experimental results indicated that the pitting potentials of MG were significantly higher than that of BSS, and the passive current densities were lower than that of BSS and high-chromium SAM2X5 amorphous steel due to the synergistic effect of Cr and Mo elements. With the temperature elevating from 30 °C to 70 °C, the passive current densities of metallic glass were increased by about one order of magnitude. The passive current temperature sensitivity for this metallic glass was closely related to the decreased Cr2O3 content, increased donor density and reduced work function of the passive film. This work provides a new insight for developing novel alloys with high corrosion resistance as well as excellent neutron absorption capacity for applications in spent nuclear fuel storage. [ABSTRACT FROM AUTHOR]

The quest for heightened energy efficiency is inextricably linked to advancements in energy storage and conversion technologies, wherein multifunctional catalysts play a pivotal role by mitigating the slow kinetics endemic to many catalytic reactions. The intricate synthesis and bespoke design of such catalysts, however, present notable challenges. Addressing this, the present study capitalizes on a novel dissolution manufacturing strategy to engineer self‐supporting, nanoporous multifunctional electrocatalysts, circumventing the prevalent issue of customizing catalytic functionalities upon demand. This innovative approach grants the flexibility to finely tune the incorporation of active species and metalloid binders, culminating in the creation of a self‐supporting nanoporous metal glass electrocatalyst doped with RuO2 (NPMG@RuO2) with outstanding performance in alkaline media. The catalyst showcases superior electrocatalytic activity, achieving low overpotentials of 41.50 mV for the Hydrogen Evolution Reaction and 226.0 mV for Oxygen Evolution Reaction alongside sustained stability over 620 hours.These achievements are attributed to the distinct nanoporous architecture that ensures a high density of catalytic sites and mechanical strength, bolstered by the synergistic interplay between RuO2 and Pt‐based metallic glass. The findings provide a versatile template for the development of nanoporous multifunctional catalysts, signifying a leap forward in the realm of energy conversion technologies. [ABSTRACT FROM AUTHOR]

A series of barium-boroaluminosilicate [30SiO 2 -11Al 2 O 3 -44B 2 O 3 -5BaO-(10-x)K 2 O-xDy 2 O 3 (with x = 0.25, 0.5, 0.75, 1.0, 1.25, 1.5 mol%)] glasses doped with Dy3+ ions were prepared by the high temperature (melt quenching) method. In the glass matrix, the relationship among structure, luminescence properties, and B/Al ratio was analyzed; also studied are the physical properties of glass and influence of Dy3+ concentration on the luminescence properties. Differential Scanning Calorimeter (DSC) results have shown the glass matrix exhibiting good thermal stability and high resistance to crystallization. FTIR and Raman spectra have confirmed the presence of stretching and bending vibrations of [BO 3 ], [AlO 4 ] and [SiO 4 ] structural units in the prepared glass. The observed UV–Vis–NIR spectra have indicated that the existence of thirteen bands corresponding to the transition Dy3+ ions from 6H 15/2 level to different excited levels; the transmittance curves obtained have shown the transmittance up to 91 %. Increase in Dy3+ concentration is found to decrease the optical band gap; the calculated Judd-Oflet parameter is found to follow the trend Ω 2 ＞Ω 4 ＞Ω 6. Photoluminescence studies have shown three emission peaks which could be associated to the transitions: 4F 9/2 → 6H 15/2 (blue light), 4F 9/2 → 6H 13/2 (yellow light), and 4F 9/2 → 6H 11/2 (red light); the maximum intensity obtained for the glass with x = 0.75 mol%, with spacing between Dy3+ ions being 1.9137 Å; and the decay curve could be fitted with double exponential function. The CIE results have revealed that the chromaticity coordinates are closer to that of standard white light, and the color temperature located in the region of cold white light. [ABSTRACT FROM AUTHOR]

Rejuvenation of glassy structures in general is characterized by the exothermic enthalpy prior to the glass transition. In the present work, we find that this situation is not applicable to a heavily-aged Zr-based metallic glass that rejuvenates by anelastic deformation before yield. Instead, its rejuvenation can be precisely captured by the low-temperature boson heat capacity peak as well as the effective enthalpy change with the glass-to-liquid transition. These results demonstrate that a structurally stable glass could rejuvenate by decreasing mechanical stability of its basin of potential energy landscape, but without changing the basin's energy level. The underlying mechanism points toward the redistribution of the atomic free volume with a constant system-averaged value. We further find that the rejuvenation limit of this glass is its steady-flow state with self-similar inherent structures at both short- and long-time scales. Our findings refresh the understanding of glass rejuvenation and suggest that the boson peak is a better probe for the structural rejuvenation of glasses. [ABSTRACT FROM AUTHOR]

The design of high‐performance structural thin films consistently seeks to achieve a delicate equilibrium by balancing outstanding mechanical properties like yield strength, ductility, and substrate adhesion, which are often mutually exclusive. Metallic glasses (MGs) with their amorphous structure have superior strength, but usually poor ductility with catastrophic failure induced by shear bands (SBs) formation. Herein, we introduce an innovative approach by synthesizing MGs characterized by large and tunable mechanical properties, pioneering a nanoengineering design based on the control of nanoscale chemical/structural heterogeneities. This is realized through a simplified model Zr24Cu76/Zr61Cu39, fully amorphous nanocomposite with controlled nanoscale periodicity (Λ, from 400 down to 5 nm), local chemistry, and glass–glass interfaces, while focusing in‐depth on the SB nucleation/propagation processes. The nanolaminates enable a fine control of the mechanical properties, and an onset of crack formation/percolation (>1.9 and 3.3%, respectively) far above the monolithic counterparts. Moreover, we show that SB propagation induces large chemical intermixing, enabling a brittle‐to‐ductile transition when Λ ≤ 50 nm, reaching remarkably large plastic deformation of 16% in compression and yield strength ≈2 GPa. Overall, the nanoengineered control of local heterogeneities leads to ultimate and tunable mechanical properties opening up a new approach for strong and ductile materials. [ABSTRACT FROM AUTHOR]

Amorphous alloys, also known as metallic glasses, are a type of novel amorphous material discovered by chance. This discovery has greatly enriched the field of metal physics, spurred the rapid development of amorphous physics and materials science, and propelled amorphous physics to the forefront of condensed matter physics. As an important and challenging branch of this discipline, amorphous physics now plays a pivotal role in understanding the complexities of non-crystalline materials. Amorphous materials, characterized by their unique properties, are not only widely used in daily life and high-tech fields but also serve as model systems for studying significant scientific issues within materials science and condensed matter physics. This paper provides a comprehensive review of amorphous alloys, discussing major scientific issues and challenges in amorphous science, the formation mechanisms of these materials, their structural characteristics, and their physical and mechanical properties. Additionally, it explores the various applications of amorphous materials and forecasts future research trends, significant issues, development prospects, and directions within this vibrant field. [ABSTRACT FROM AUTHOR]

Amorphous metals are increasingly used as advanced engineering materials, due to several desirable properties, like high hardness and ductility, high resilience, high mechanical strength and high wear resistance, among others. However, many details of the mechanical behavior of amorphous metals are still unknown, and currently used models and theories are far from predictive. Here we use atomistic molecular dynamics (MD) simulations to study the mechanical behavior of an amorphous Cu 46 Zr 54 sample, focusing on temperature effects on the tension-compression asymmetry. We find a large tension-compression asymmetry in plastic yielding, and an expected softening of the material as temperature is increased. We observe the formation of shear bands and, under tension, void nucleation leads to significant stress relaxation. The behavior of icosahedra-like polyhedra versus strain correlates with the onset of plastic behavior. The temperature-dependent softening response follows a T 2 / 3 -relationship as discussed in previous studies. [ABSTRACT FROM AUTHOR]

Measuring pH with an optical sensor requires the immobilization of a chemical recognition phase on a solid surface. Neutral red (NR), an acid base indicator was used to develop two different optical probe configurations. The chemistry of aryl diazonium salts was chosen for the elaboration of this chemical phase, as it enables strong covalent bonds to be established on the surface of metallized glass or metallic surfaces. It also allows the formation of a thick film required to obtain an exploitable spectral response. The surfaces of interest (metallized optical fiber and 316 L stainless-steel mirror) are modelized by flat surfaces (metallized glass plates and 316 L stainless-steel plates). The analytical characterizations carried out (IR, XPS, UV-Visible, and profilometry) show that NR was covalently grafted onto the model surfaces as well as on the surfaces of interest. The supports grafted with NR to develop optical pH probes exhibit spectral changes, particularly the values of pKa, the pH range, and the isosbestic point wavelength. The experimental results show that the optical probe can be used for pH measurements between 4 and 8. [ABSTRACT FROM AUTHOR]

The performance of ab initio descriptors derived from density functional theory simulations is systematically investigated in comparison to traditional compositional descriptors for the ability to predict glass properties utilizing machine learning algorithms. Two datasets are used for this purpose: an extensive, publicly available database involving a wide range of oxide glasses, and a small in‐house dataset covering a broader collection of inorganic glasses from metallic to non‐metallic materials. For the larger dataset, it was demonstrated that ab initio descriptors offer a substantial reduction in input dimensionality while retaining nearly equivalent predictive performance when compared to the compositional descriptors. The combination of ab initio and compositional descriptors showed an improvement in prediction accuracy. For the smaller dataset, the ab initio‐derived descriptors performed significantly better than the compositional descriptors, providing a valuable tool to improve glass property prediction in settings where the availability of data is limited. Furthermore, ab initio‐derived descriptors are not only computationally inexpensive and allow extrapolation beyond the training composition space but also facilitate model interpretation. [ABSTRACT FROM AUTHOR]

In the present work nano-sized TiN powders were consolidated and sintered in nitrogen, argon and air using microwave power of 900 W at frequency 2.45 GHz. Green compacts were exposed to microwave energy, and heated at an in-situ temperature of 1500 °C without holding time. The relative density achieved was ∼92 %. X-ray diffraction analysis showed presence of TiN as the dominant major phase. The microstructures indicate that the sintered samples retained their nanocrystallinty, though aggregates comprising clusters of nanoparticle was noticed with size in the range of 80–400 nm due to high heating rate. Micro indentation assessment indicates average Vickers hardness of 15.2 ± 0.5 GPa. The lengths of cracks originating from the indentation edges were measured; the indentation fracture toughness were obtained between 4.0 and 4.5 MPa.m1/2. The observed properties indicate the suitability of the sintered material in tribological applications. [Display omitted] • TiN ceramics without binders and additives was processed using microwave energy. • Use of SiC and graphite powder susceptors significantly reduced processing time. • Compacts sintered at high heating rate attained ∼92 % relative density. • Sintering was accomplished with comparable mechanical properties while retaining nanocrystallinity. [ABSTRACT FROM AUTHOR]