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In multicomponent lattice problems, for example, in alloys and at crystalline surfaces and interfaces, atomic arrangements exhibit spatial correlations that dictate the kinetic and thermodynamic phase behavior. These correlations emerge from interparticle interactions and are frequently reported in terms of the short-range order (SRO) parameter. Expressed usually in terms of pair distributions and other cluster probabilities, the SRO parameter gives the likelihood of finding atoms/molecules of a particular type in the vicinity of other atoms. This study focuses on fundamental constraints involving the SRO parameters that are imposed by the underlying lattice topology. Using a data-driven approach, we uncover the interrelationships between different SRO parameters (e.g., pairs, triplets, and quadruplets) on a lattice. The main finding is that while some SRO parameters are independent, the remaining are collinear, i.e., the latter are dictated by the independent ones through linear relationships. A kinetic and thermodynamic modeling framework based on these constraints is introduced. [ABSTRACT FROM AUTHOR]

Although XLPE cables are widely used in power transmission and distribution systems, their insulating properties are susceptible to degradation due to thermal aging. In order to clarify the influence law of the thermal aging process on the structural and dielectric properties of XLPE cables, this paper investigates the thermal aging characteristics of XLPE cables by using polarization and depolarization current measurement. Results show that when the XLPE cable is aged at 140 °C, the crystallinity of the insulation layer appears to increase and then decrease. With the increase in aging time, micron-sized microvoids appear on the surface of the XLPE. At the same time, the DC conductivity and 0.1 Hz dielectric loss factor of the insulating layer increase with the aging time. The average DC conductivity increased from 2.26 × 10−16 S/m for new cables to 4.47 × 10−16 S/m after aging for 432 h, while the dielectric loss increased from 0.11% to 0.42%. The polarization characteristics of thermal-aged cables were further analyzed using the extended Debye model. Results indicate that the time constant of the third branch of the model increased significantly with increasing aging time. A correspondence between this parameter and the thermal aging time of the cable was established. Thermal aging can damage the crystalline structure of XLPE, so that the number of interfaces between the crystalline and amorphous regions of the material increases, resulting in structural damages and a decline in the dielectric properties of the cable insulation. [ABSTRACT FROM AUTHOR]

Experiments have shown that high strength and high plastic stability are difficult to be simultaneously obtained in crystalline-amorphous layered composites. Here we report a complete suppression of plastic instability in a strong multilayered composite via nanoscale BCC Nb crystalline-amorphous CuNb interface architecting. Specifically, the size-dependent hardness and shear instability of the designed nanolayered composites are systematically investigated with individual layer thickness (h) ranging from 2 to 100 nm by nano/micro-indentation tests. A mechanics model is also proposed to quantify the shear instability. A non-monotonic shear instability behavior is revealed with decreasing h. When h > 40 nm, a cutting-like shear banding prevails in the composites and the shear instability reduces with decreasing h. Finally, a homogeneous plastic deformation without shear banding is achieved at h of 40 nm. For h < 40 nm, a kinking-like shear banding occurs in the composites and the shear instability increases with reducing h. Further theoretical analysis reveals a critical layer thickness for activating homogeneous deformation in the composites, i.e., 45 nm, above and below which the shear deformation would be dominated by cutting-like and kinking-like shear banding, respectively. The cutting-like shear banding is attributed to the propagation of the mature shear band formed in the amorphous phase that penetrates the crystalline layer. The homogeneous plastic deformation can be ascribed to the activation of the confined layer slip mechanism in the crystalline layer and the non-clustered shear transformation zones initiated in the amorphous layer. The kinking-like shear banding below 40 nm may originate from the cooperative kinking of the constituent layers with decreasing h. The potential advantage of the ductile BCC metals over FCC ones for suppression of shear instability in crystalline-amorphous composites is discussed based on the unique dislocation activities in nanoscale BCC crystals (e.g., self-multiplication and significant cross-slipping mechanisms). The present study sheds some light on designing strong and ductile crystalline-amorphous composites by selecting an appropriate BCC crystalline phase and an optimal interface spacing to eliminate plastic instability. • Shear instability of Nb/amorphous CuNb nanolayered composites is studied. • A mechanics model is proposed to quantify the shear instability. • A non-monotonic shear instability is discovered with decreasing layer thickness. • Shear instability is fully suppressed at 40 nm sample. • Cutting and kink-like shear bandings prevail respectively at large and small scales. [ABSTRACT FROM AUTHOR]

A novel electrocatalyst containing amorphous FeSeO x and Mo doped NiSe 2 (denoted as FeSeO x /Mo-NiSe 2) was developed via pseudocrystalline replication method and selenization treatment, and heteroatom doping and amorphous and crystalline (a-c) interface enables attractive OER performances. [Display omitted] • A novel FeSeO x /Mo-NiSe 2 electrocatalyst was desinged for water oxidation. • The optimized FeSeO x /Mo-NiSe 2 exhibits a low overpotential of 205 mV at 10 mA cm−2 for OER in alkaline solution. • The excellent performance is attributed to amorphous and crystalline (a-c) interface engineering and heteroatom doping strategies. Exploring integrated regulation strategies to boosting electrocatalytic performance is essential to design more efficient and inexpensive OER catalysts. Herein, amorphous and crystalline (a-c) interface engineering and heteroatom doping are integrated to construct a novel electrocatalyst containing amorphous FeSeO x and crystalline Mo-doped NiSe 2 (denoted as FeSeO x /Mo-NiSe 2) via pseudocrystalline replication method and selenization treatment. The resultant FeSeO x /Mo-NiSe 2 electrocatalyst with 3D hierarchical nanoarchitectures of nanorod arrays covered by interlocking nanoblocks exposes more active sites and accelerated reaction kinetics. Furthermore, a-c interface engineering and heteroatom doping can synergistically enhance the intrinsic activity and charge transfer capability of NiSe 2 by decreasing the electron diffusion distance and flexibly modulating the electronic structure, which contributes to boost the oxygen evolution reaction (OER) performance. Consequently, the obtained FeSeO x /Mo-NiSe 2 achieves a low overpotential of 205 mV at 10 mA cm−2, which outperforms many other transitions metal selenides electrocatalysts. Density functional theory (DFT) calculations demonstrate that the formation of an internal electric field between FeSeO x and Mo-NiSe 2 accelerates charge transport and optimizes the adsorption/desorption of oxygen-containing intermediates, thereby accelerating the reaction kinetics and improving the OER performance. This work serves as a point of reference for designing innovative metal selenides based electrocatalysts combining a-c interface engineering and heteroatom doping. [ABSTRACT FROM AUTHOR]

Reaching near-zero friction is one of the jewels on the crown of tribology, and structural superlubricity is a crucial mechanism to achieve it. Previous works focus mainly on the structural superlubricity at incommensurate crystalline interfaces. However, realizing such interfaces on a large scale without defects and contaminations is a formidable challenge. Here, we report a charge-induced robust macroscale superlubricity between graphite and atomically flat surfaces in the ambient condition. We transferred graphite flakes on Si 3 N 4 balls and used them to measure the friction properties on pristine and charged atomically flat surfaces such as 300 nm SiO 2 /Si and sapphire. We found that the surface charge can dramatically reduce the coefficient of friction between graphite and substrates by two orders of magnitude to 10−4, and the sliding is wearless even under harsh contact conditions (∼1.1 GPa center pressure and >100 m). We demonstrate that the surface charge is critical in achieving superlubricity possibly because it can reduce adhesion between graphite and substrate surfaces and make the substrate surfaces resistant to contaminations. Our method offers a ready-to-use solution to superlubricity alternative to achieve incommensurate crystalline interfaces. Thus, it can reduce the difficulty of realizing macroscale superlubricity for applications. [Display omitted] • The surface charge can reduce the coefficient of friction between graphite and atomically flat surfaces to 10−4. • The sliding between graphite and charged surfaces is wearless under harsh conditions (∼1.1 GPa center pressure, >100 m). • The surface charge can reduce the adhesion between graphite flake and substrate surface by 50%. [ABSTRACT FROM AUTHOR]

Phonon diffraction and interference patterns are observed at the atomic scale, using molecular dynamics simulations in systems containing crystalline silicon and nanometric obstacles, such as voids or amorphous inclusions. The diffraction patterns due to these nano-architectured systems of the same scale as the phonon wavelengths are similar to the ones predicted by the simple Fresnel–Kirchhoff integral. The few differences between the two approaches are attributed to the nature of the interface and the anisotropy of crystalline silicon. Based on the wave description of phonons, these findings can provide insights into the interaction of phonons with nano-objects and can have applications in smart thermal energy management. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are performed to investigate the effect of the interface structure, diffusion time and diffusion temperature on the diffusion behavior and amorphization mechanism of the dual-phase Mg alloys. The results indicate that there is a critical concentration of Y element in the amorphous/crystalline interface (ACI), which depends on the interface structure and temperature. And when the concentration of Y atoms in the ACI is higher than the critical concentration, the ACI will migrate towards the crystalline side, accompanied by the amorphization of the crystalline layer. In addition, it is found that the presence or absence of Y element in the amorphous layer has a significant impact on the amorphous layer thickness of the alloys. For the alloys containing Y atoms, the amorphous layer thickness increases with the increase of diffusion temperature and diffusion time. [ABSTRACT FROM AUTHOR]

Sodium ion batteries (SIBs) have garnered more and more attentions owing to the uneven distribution and increasing price of lithium mineral. Herein, BiVO 4 –V 2 C endogenous heterostructures as anode for SIBs are synthesized via one-step in situ hydrothermal method. The designed hydrangea-like heterostructure ensures a wide contact surface for the interaction of anode material with the electrolyte, and endows stable heterojunction interfaces between BiVO 4 and V 2 C MXene, the synergistic effect of which significantly improves the electrical conductivity, pseudo-capacitance and alleviates the volumetric change of BiVO 4 during charge/discharge process. Density functional theory (DFT) calculations ulteriorly demonstrate that the electric field at the BiVO 4 –V 2 C interface contributes to the excellent Na ion diffusion kinetics and impressive sodium storage capacity. As a result, the BiVO 4 –V 2 C anode achieved outstanding performance with a high discharge capacity (480 mAh g−1 after 600 cycles at 0.2 A g−1), and impressive long-term lifespan (303 mAh g−1 over 2000 cycles at 1 A g−1). This work reveals a new design of novel V 2 C MXene heterojunctions which coupling with BiVO 4 combined with the analysis of amorphous/crystalline interface, developing a proper strategy for the effective energy storage of sodium. An endogenous heterostructure of BiVO 4 coupled with V 2 C MXene (BiVO 4 –V 2 C) is developed via a one-step hydrothermal method. The designed hydrangea-like heterostructure provides a large surface area for the contact of the electrode material with electrolyte, and endows stable heterojunction interfaces between BiVO 4 and V 2 C, which significantly improves the reaction kinetics. [Display omitted] • Hydrangea-like endogenous BiVO 4 –V 2 C heterostructure is firstly reported. • Internal micro-electric field for improving Na+ migration and reaction kinetics. • The electrode delivers superior specific capacity and excellent cycle stability. • Endogenous heterostructure offers new insights for MXenes heterojunctions design. [ABSTRACT FROM AUTHOR]

Mechanical deformation of Cu 50 Zr 50 metallic glasses (MGs) with CuZr B2 layers was explored using tensile tests under iso-strain and iso-stress conditions using molecular dynamics simulations. Atomic structure identification was conducted through machine learning techniques, enabling a distinct examination of the deformation exhibited by each phase. Our results revealed early-stage plasticity driven primarily by shear transformation zones at the amorphous/crystalline interface, rather than shear band formation and propagation observed in the monolithic MG, leading to nanolaminates with enhanced strength. Furthermore, under iso-strain deformation, B2 layers underwent martensitic transformation promoted by the nucleation of voids. However, void growth quickly supersedes these effects under both iso-strain and iso-stress conditions, culminating in sample fracture. In summary, this work advances our understanding of amorphous/crystalline nanolaminates, providing valuable insights into their mechanical complexities. • Structure identification is performed based on machine learning techniques. • Amorphous/crystalline interfaces promote plasticity, hindering shear band propagation. • Void growth induce martensitic transformation in the B2 layer under iso-strain condition. • Void growth quickly dominates plastic deformation resulting in fracture. [ABSTRACT FROM AUTHOR]

The CoFeLDH@Ni 2 P electrocatalyst was fabricated via a facile hydrothermal and electrodeposition process. Benefitting from the amorphous/crystalline (a-c) interfaces and modified electronic structure, CoFeLDH@Ni 2 P exhibits remarkable saline water splitting performance, requires cell voltages of 1.56 V to deliver 10 mA cm−2. The strongly negative charge surface and formed PO 4 3− selectively rejects Cl−, endowing its high tolerance in saline electrolytes. [Display omitted] • Amorphous CoFeLDH-crystalline Ni 2 P heterostructures were constructed. • Vertically aligned structure endows CoFeLDH@Ni 2 P with abundant active sites. • Different surface reconstruction behavior for CoFeLDH@Ni 2 P during HER/OER. • PO 4 3− and more negative charge surface improves anti-corrosive properties. Developing electrocatalysts with high activity and robust performance for large-scale seawater electrolysis to produce hydrogen holds immense significance. Herein, a highly active bifunctional electrode composed of amorphous cobalt-iron layered double hydroxides (CoFeLDH) and crystalline nickel phosphide (Ni 2 P) (denoted as CoFeLDH@Ni 2 P), is employed to boost hydrogen production through seawater electrolysis. The strong interface coupling effectively modifies the electronic structure at active sites, thereby accelerating the catalytic reaction kinetics. Impressively, in situ Raman and post-stability analyses demonstrate a unique reconstruction behavior on the CoFeLDH@Ni 2 P electrode. Bimetal co-incorporated NiOOH (CoFe-NiOOH) and Ni(OH) 2 species are formed during the oxygen evolution reaction (OER), while CoFeLDH@Ni 2 P can transform into Ni(OH) 2 species during the hydrogen evolution reaction (HER) process. Furthermore, the highly negatively charged surface selectively rejects Cl− ions by formed PO 4 3−, endowing CoFeLDH@Ni 2 P with excellent tolerance and promising durability in saline electrolytes. Consequently, the CoFeLDH@Ni 2 P electrode exhibits an overpotential of 106 mV for HER at 10 mA cm−2 and 308 mV for OER to achieve 100 mA cm−2 in 1.0 M KOH solution. Additionally, the CoFeLDH@Ni 2 P (+,-) electrolyzer requires a low cell voltage of 1.56 V to deliver 10 mA cm−2 in 1.0 M KOH + Seasalt. This work presents an appealing strategy for the rational design of advanced electrocatalysts with amorphous-crystalline interfaces, which reveals the source of the activity of transition-metal phosphating compounds in saline water electrolysis. [ABSTRACT FROM AUTHOR]

Surface reconstruction that produces real active species for catalytic reactions generally occurs during electrocatalytic water splitting, but overcoming the reconstruction level‐mass activity‐stability trade‐off is a grand challenge. A cation‐doping in conjunction with a geometrical topology strategy is proposed to concurrently realize deep reconstruction and self‐optimization of FeNi phosphide nanoarrays during an electrochemical activation process. The doped Zn cation induces a deep reconstruction of FeNiP@Fe2P precatalyst by continuously dissolving Fe2P and re‐depositing as amorphous FeOOH that solders Ni2P nanoparticles, forming small ultra‐thin nanosheets with abundant amorphous‐crystalline interfaces for structural stability. Moreover, multichannel topology exhibits an unusual ability to optimize their morphology via finally evolving into multi‐microchannel tubular nanoarrays comprising of interconnected‐nanosheets with a very loose structure for enhanced electrolyte permeability, mass transfer, and accessibility of active sites. The reconstructed Zn‐Ni2P/FeOOH superstructure catalysts reach 10 mA cm−2 current density at an ultra‐low overpotential of 11 mV for hydrogen evolution reactions (HER). Impressively, when assembled as a two‐electrode cell with Zn‐FeNiP@Zn‐Fe2P as anode and Zn‐Ni2P/FeOOH as cathode, it delivers current densities of 10 mA cm−2 at a record low cell voltage of 1.40 V. This strategy provides a novel avenue to promote reconstruction for achieving high catalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anthracene-appended poly(ʟ-lactide)s (AAP) were synthesized by ROP of ʟ-lactide. • The excimer emission was observed in the low molecular weight AAP. • The monomeric emission is observed in amorphous and single crystals of AAP. • In crystallized AAP, fluorescence arises from anthracene excimers and monomers. • In the gel state AAP (e form), only the excimer emission was observed. The design and development of solid-state excimer-emitters bear great potential for attaining efficient solid-state luminescent materials. In this study, we have synthesized anthracene-appended poly(ʟ-lactide)s (AAPs) to regulate the arrangement of anthracene moieties by controlling the crystallization and polymorphic form of covalently linked poly(ʟ-lactide) (PLLA). In the high molecular weight AAP, the fluorescence intensity mainly arises from the monomeric anthracene moieties, whereas in the low molecular weight AAP, the excimer emission was observed depending on the structure and morphology of covalently-linked PLLA. The monomeric emission is predominantly observed in amorphous polymer due to the molecular level dispersion of covalently-linked anthracene moieties throughout the polymer matrix. When the polymer was crystallized under different conditions, covalently-linked anthracene moieties were excluded from polymer crystals or crystalline lamellae and are located on the surface or at the interface, which is advantageous for regulating the geometry of anthracene moieties. In the case of single crystals of PLLA, covalently-linked anthracene moieties assemble on the surface and emit mainly in their monomeric state due to the lack of π-stacking. In the melt-crystallized sample (α form), covalently-linked anthracene moieties reside at the interface of crystalline and amorphous domains by either dipolar interactions or π-stacking and fluorescence arising from anthracene excimers and monomers. In the gel state (ε form), only the excimer emission was observed due to the effective interactions between the anthracene moieties in the presence of excess solvent in the amorphous domains. In this way, polymer crystallization played a significant role in determining the arrangement of covalently-linked anthracene moieties in AAP. This study reveals the role of polymer crystallization on the excimer evolution in fluorophore-appended semicrystalline polymers and provides new insight into the design and development of fluorophore-appended polymers for optoelectronic devices. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction reaction (CO2RR) provides a promising way for producing value‐added fuels and chemicals via renewable electricity. However, the dynamic reconstruction of electrocatalysts of atomic active sites hinders in‐depth understanding of catalytic mechanism and further industrial application, especially under ampere‐level current density conditions. In this work, electro‐induced crystallization is reported over an amorphous Indium hydroxide gel (In gel) catalyst, which generates active sites for efficient and selective CO2RR. Molecular dynamic calculation reveals the crystallization process can maintain amorphous In‐OH species on the surface while generating crystallized metallic In under electroreduction condition; structural characterizations prove that the derived partially crystallized In gel is stable consisting of amorphous/crystalline interface, even biased at a high polarization potential of −4 V versus reversible hydrogen electrode. The resultant partially crystalized In gel exhibits a highly selective CO2RR performance toward formate under an ampere‐level current density up to 1200 mA cm−2 simultaneously with 91.89% Faradaic efficiency, which can motivate a high formate generation rate of 20.55 mmol h−1 cm−2. The operando Raman spectroscopic and density functional theoretic results demonstrate the optimized adsorption of *HCOO intermediate for the enhanced formate activity and selectivity over the partially crystallized In gel. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous RuSe 2 electrocatalysts with abundant amorphous-crystal interfaces were synthesized. • The amorphous structure is conducive to the adsorption of H 2 O molecules. • The crystalline structure provides an optimal the free energy of hydrogen adsorption (ΔG H*). • RuSe 2 -400 °C featuring coexistence of crystal and amorphous structures, exhibited an overpotential of 27 mV superior to Pt/C at 10 mA cm-2. Transition metal chalcogenides have garnered considerable attention as high-performance electrocatalysts for the hydrogen evolution reaction (HER). Enriching their structural properties through constructing a porous architecture and creating crystalline-amorphous interfaces holds promise for enhancing HER performance. In this study, porous RuSe 2 electrocatalysts with varying crystallinities (i.e., amorphous, amorphous-crystal, and crystal) were synthesized using a straightforward hydrothermal method followed by a subsequent annealing process. Comparable experiments indicate that porous RuSe 2 -400°C, featuring a crystalline-amorphous structure, exhibited enhanced catalytic activity compared to its amorphous and crystalline counterparts. The porous architecture and interfacial sites between crystalline and amorphous phases in RuSe 2 -400°C not only integrate the critical factors of abundant unsaturated coordination sites and good electrical conductivity but also modify its surface electronic state, which can optimize the adsorption energies of reaction intermediates. As a result, the optimized samples displayed remarkable HER activity in an alkaline medium, showcasing an extremely low overpotential of 27 mV at 10 mA cm-2 and a Tafel slope of 39.8 mV dec-1. This study provides a platform for rationalizing high-perform porous electrocatalysts with rich amorphous/crystalline interfaces. [ABSTRACT FROM AUTHOR]

The thermal stability of crystalline-amorphous interfaces was investigated in Fe/FeW nanomultilayers (NMs), where the alloy layers were amorphous in the as-sputtered state with concentrations of Fe-38 at.% W or Fe-67 at.% W. Compositionally driven devitrification, layer breakdown, and recrystallization were compared using both single-layer and multilayer configurations at temperatures ranging from 250 °C to 750 °C. Annealing of the NMs to 500 °C revealed destabilization in the Fe-67 W layers with the formation of crystalline-crystalline interfaces (CCIs) whereas the Fe-38 W layers remained intact with stable crystalline-amorphous interfaces (CAIs). Further annealing to 750 °C resulted in multilayer evolution and recrystallization, where breakdown of the CAIs was attributed to layer intermixing while the CCIs experienced intermetallic grooving and pinch-off. The influence of amorphous stability, composition, and intermetallic formation are discussed with respect to the NM breakdown mechanisms. This work highlights a promising strategy for exploring compositionally driven stability at the nanoscale in crystalline-amorphous alloys. [Display omitted] [ABSTRACT FROM AUTHOR]

• Nanoscale ferroelectric domain switching of undoped HfO 2 were investigated. • Well-controlled thermal stress can enhance polarization strength of undoped HfO 2. • Ferroelectric negative capacitance effect can be improved by thickness scaling. • Undoped HfO 2 NCFET with tight hysteresis distribution can be achieved. In this work, we investigated the polarization characteristics of nanoscale undoped hafnium oxide (HfO 2) ferroelectric film. The nanoscale domain switching behavior of undoped HfO 2 is mainly dominated by mixed ferroelectric/nonferroelectric crystalline phases and interface domain pinning by oxygen vacancies or defect traps. Our experimental results confirm that these issues can be improved by film thickness scaling and well-controlled mechanical stress. We demonstrated a 4-nm-thick undoped HfO 2 negative capacitance thin film transistor (NCFET) with an energy-efficient switch characteristic of a low overdrive voltage of -0.6 V, a steep subthreshold swing of sub-60 mV/dec and a uniform hysteresis distribution of sub-60 mV. [ABSTRACT FROM AUTHOR]

• A method for developing models of realistic CASS microstructure is shown. • Simulated sound fields in CASS models agree well with experimental sound fields. • Simplified CASS models using Voronoi regions outperformed the realistic CASS models. • Large variations in echo amplitude were observed when randomizing the CASS model microstructure. Ultrasonic inspection of cast austenitic stainless steel (CASS) in the nuclear industry is particularly challenging because of sound field scatter and attenuation caused by the coarse-grained microstructure. Modeling and simulation are important tools in ultrasonic testing, as they can be used to help address key aspects of inspections, such as developing new probe designs, predicting inspection reliability, and testing phased-array focal laws. However, developing a useful and reliable CASS model is challenging due to the many grain interfaces and crystalline orientations that must be captured. We demonstrate a method of creating a realistic CASS model that is usable in CIVA, a commercially available modeling and simulation software platform. Using polished and chemically etched sections to highlight the grain structure and orientation, we generate models of a coarse-grained equiaxed specimen and a columnar specimen. We also test an alternative method of generating a coarse-grained model using Voronoi regions. We qualitatively compare sound field scatter and quantitatively compare sound field attenuation and beam partitioning in simulated sound fields to those of laboratory-measured sound fields. Results show that the Voronoi models perform as well as or better than the models based on actual grain morphology. We also show that model-to-model randomness in Voronoi grain structure can impact the magnitude of a simulated echo response by a factor of two or more. Although CASS models are potentially a good depiction of reality for a given scenario, they should not be considered representative since CASS morphology can change significantly from specimen to specimen or within the same specimen. [ABSTRACT FROM AUTHOR]