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The stability of perovskite materials is profoundly influenced by the presence of moisture in the surrounding environment. While it is well-established that water triggers and accelerates the black–yellow phase transition, leading to the degradation of the photovoltaic properties of perovskites, the underlying microscopic mechanism remains elusive. In this study, we employ classical molecular dynamics simulations to examine the role of water molecules in the yellow–black phase transition in a typical inorganic metal halide perovskite, CsPbI3. We have demonstrated, through interfacial energy calculations and classical nucleation theory, that the phase transition necessitates a crystal–amorphous–crystal two-step pathway rather than the conventional crystal–crystal mechanism. Simulations for CsPbI3 nanowires show that water molecules in the air can enter the amorphous interface between the black and yellow regions. The phase transition rate markedly increases with the influx of interfacial water molecules, which enhance ion diffusivity by reducing the diffusion barrier, thereby expediting the yellow–black phase transition in CsPbI3. We propose a general mechanism through which solvent molecules can greatly facilitate phase transitions that otherwise have prohibitively high transition energies. [ABSTRACT FROM AUTHOR]

When chloroaluminate ( A l C l 4 − ) serves as the electrolyte, aluminum nitride (AlN) has shown promise as a cathode material in aluminum ion batteries. However, there is currently a lack of research on the mechanisms of charge transfer and cluster intercalation between AlCl4 and AlN cathode materials. Herein, first-principles calculations are employed to investigate the intercalation mechanism of AlCl4 within the AlN cathode. By calculating the formation energies of stage-1–5 AlN–AlCl4 intercalation compounds with the insertion of individual AlCl4 cluster, we found that the structure of the stage-4 intercalation compounds exhibits the highest stability, suggesting that when the clusters begin to intercalate, it is important to start with the formation of the stage-4 intercalation compounds. In the subsequent phases of the charging process (stages 1 and 2), the stabilized structure with four inserted clusters demonstrates two characteristics: the coexistence of standing and lying clusters and the insertion of two standing clusters in an upside-down doubly stacked configuration, which further improve the spatial utilization while maintaining the structural stability. In addition, we infer that a phenomenon of coexisting intercalation compounds with mixed stages will occur in the course of the charging and discharging processes. More importantly, the diffusion barrier of AlCl4 in AlN–AlCl4 intercalation compounds decreases with the reduction of stage number, ensuring the rate performance of batteries. Therefore, we expect that our work will contribute to comprehend the intercalation mechanism of AlCl4 into the AlN cathode materials of aluminum ion batteries, providing guidance for related experimental work. [ABSTRACT FROM AUTHOR]

Tiny NiSnO3 nanoparticles with the assistance of polyvinylpyrrolidone (PVP) are prepared to uniformly and stably "bond" on the surface of graphene to form a stable NiSnO3/RGO-PVP structure. At the same time, the excellent performance of lithium-ion batteries (LIBs) with the use of NiSnO3/RGO-PVP structure is verified through a dual combination of experiment and theory. The resulting NiSnO3/RGO-PVP structure enhanced the performance of LIBs with high cycling stability and better rate capability; even after undergoing rate performance tests at different high current densities, the NiSnO3/RGO-PVP electrode can still reach a capacity of 624 mA h g−1 at 200 mA g−1 after 400 cycles. The superior electrochemical performance of NiSnO3/RGO-PVP nanocomposites can be attributed to the synergistic effects between tiny NiSnO3 nanoparticles synthesized with the assistance of PVP and RGO, which can be verified through first-principles calculations based on DFT. The charge transfer between NiSnO3 and RGO through an electron density difference indicates a strong interaction between the two. Meanwhile, the low adsorption energies (−3.914, −0.77, and −0.65 eV), low diffusion barriers (0.025, 0.49, and 0.141 eV), and high diffusion coefficients (1.79 × 10−3, 5.38 × 10−11, and 2.97 × 10−5 cm2 s−1) of lithium ions at three different positions indicate the excellent rate performance of the NiSnO3/RGO-PVP heterostructure, which is consistent with experimental results. This work analyzes the excellent electrochemical performance of NiSnO3/RGO-PVP from the experimental results and supports the reliability of the experimental results through theoretical calculations. [ABSTRACT FROM AUTHOR]

One of the challenges in the semiconductor industry is to find new barrier materials and copper (Cu) alternative solutions in interconnects. In this work, we focused to find alternative diffusion barrier materials. Different binary (CoMo, CoRu, CoTa, CoW, MoRu, RuTa, RuW) and ternary (CoMoTa, CoRuTa, MoRuTa) metal alloys were evaluated theoretically with the Miedema model to find the amorphous phase composition range. Afterward, thin films of the alloys with various compositions were deposited by magnetron sputtering and theoretical values were compared to the experimental results. From the experimental measurements, which included grazing incidence x-ray diffraction analysis and resistivity measurements, suitable binary and ternary alloys were chosen for diffusion analysis. By annealing thin film stacks at temperatures ranging from 500 to 675 ° C, diffusion was induced and detected by x-ray photoelectron spectroscopy depth profiles. Seventeen alloys were evaluated by their diffusion barrier effectiveness, and five of those, which include Ru 60 Ta 40 , Ru 45 W 55 , Mo 47 Ru 53 , Mo 36 Ru 50 Ta 14 , and Co 40 Mo 35 Ta 25 , showed excellent barrier properties against copper diffusion. Furthermore, all of the stated materials have a lower resistivity than TaN. Last, the adhesion of the best performing alloys to SiCOH and Cu was evaluated by the modified edge lift-off test. Only Ru 45 W 55 had reasonable adhesion at both interfaces. The other materials showed low adhesion strength to Cu, which would make an adhesion promoter (liner), such as cobalt, necessary for the integration. [ABSTRACT FROM AUTHOR]

Uranium-based materials are valuable assets in the energy, medical, and military industries. However, understanding their sensitivity to hydrogen embrittlement is particularly challenging due to the toxicity of uranium and the computationally expensive nature of quantum-based methods generally required to study such processes. In this regard, we have developed a Chebyshev Interaction Model for Efficient Simulation (ChIMES) that can be employed to compute energies and forces of U and UH3 bulk structures with vacancies and hydrogen interstitials with accuracy similar to that of Density Functional Theory (DFT) while yielding linear scaling and orders of magnitude improvement in computational efficiency. We show that the bulk structural parameters, uranium and hydrogen vacancy formation energies, and diffusion barriers predicted by the ChIMES potential are in strong agreement with the reference DFT data. We then use ChIMES to conduct molecular dynamics simulations of the temperature-dependent diffusion of a hydrogen interstitial and determine the corresponding diffusion activation energy. Our model has particular significance in studies of actinides and other high-Z materials, where there is a strong need for computationally efficient methods to bridge length and time scales between experiments and quantum theory. [ABSTRACT FROM AUTHOR]

A layered sodium-ion battery cathode, O3/P3/P2-type NaNi1/3Mn1/3Fe1/3O2, has been systematically investigated by first-principles density functional theory to explore the detailed structural and Na-ion diffusion behavior during desodiation. Our results suggest that the (NaO6) spacing is greatest in the P3 phase and lowest in the O3 phase, with the P2 phase exhibiting intermediate spacing. During desodiation, the intermediate stages have a greater (NaO6) spacing than the initial and final stages. The great (NaO6) spacing facilitates the formation of the P3 phase, resulting in the structural evolution of NaxNi1/3Mn1/3Fe1/3O2 from the O3 to the P3 phase at x ≈ 0.59, finally reaching the O3 structure again at x ≈ 0.12. The electronic structure clearly proves that both Ni and Fe are active in O3/P3/P2-type NaxNi1/3Mn1/3Fe1/3O2. Ni2+ is oxidized to Ni3+ as Na content decreases from x = 1 to x = 0.66, then further oxidized to Ni4+ at x = 0.33, and finally, Fe3+ → Fe4+ oxidation occurs at x = 0. In the Na ion diffusion behavior, the order of the barrier is O3 (0.82 eV) > P2 (0.53 eV) > P3 (0.35 eV) at the initial stage, whereas it is O3 (0.53 eV) > P3 (0.21 eV) > P2 (0.16 eV) at a highly desodiated stage. The former can be traced back to the (NaO6) spacing, but the latter is related to the different Na sites. Our results thus provide a factor of the structural evolution and Na ion diffusion barrier by considering (NaO6) width and Na site changes during desodiation. [ABSTRACT FROM AUTHOR]

Copper (Cu) interconnections have been widely used in advanced electronic packaging due to their outstanding thermal and electric properties. Preparing a smooth and uniform Cu seed thin layer is one of the critical processes to obtain high-reliability Cu interconnections. The barrier layer between Cu and silicon (Si) devices is necessary to prevent the inter-diffusion between Cu and Si. However, little work has been done on the surface roughness analysis of the Cu seed layer deposited on the diffusion barrier layer. In this paper, the influences of deposition thickness, incident energy, barrier layer temperature, and surface morphology on the surface roughness of the Cu seed layer deposited on α-titanium (α-Ti) barrier layer were studied in detail by the molecular dynamics (MD). The simulation results indicated that appropriate parameters have a beneficial effect on reducing the surface roughness, and the surface morphology of the Cu seed layer strongly connects with that of the barrier layer. These results provided a foundation for optimizing the quality of the Cu seed layer. [ABSTRACT FROM AUTHOR]

Bimetallic, reactive multilayers are uniformly structured materials composed of alternating sputter-deposited layers that may be ignited to produce self-propagating mixing and formation reactions. These nanolaminates are most commonly used as rapid-release heat sources. The specific chemical composition at each metal/metal interface determines the rate of mass transport in a mixing and formation reaction. The inclusion of engineered diffusion barriers at each interface will not only inhibit solid-state mixing but also may impede the self-propagating reactions by introducing instabilities to wavefront morphology. This work examines the effect of adding diffusion barriers on the propagation of reaction waves in Co/Al multilayers. The Co/Al system has been shown to exhibit a reaction propagation instability that is dependent on the bilayer thickness, which allows for the occurrence of unstable modes in otherwise stable designs from the inclusion of diffusion barriers. Based on the known stability criteria in the Co/Al multilayer system, the way in which the inclusion of diffusion barriers changes a multilayer's heat of reaction, thermal conductivity, and material mixing mechanisms can be determined. These factors, in aggregate, lead to changes in the wavefront velocity and stability. [ABSTRACT FROM AUTHOR]

Adsorption, desorption, and diffusion dynamics of hydrogen gas molecules over a hexagonal ZnO monolayer have been studied thoroughly in the van der Waals Density Functional Theory (vdW-DFT) framework in association with kinetic Monte Carlo (kMC) simulations. Hydrogen molecules can attach to a ZnO sheet via a weak physisorption process with a limitation of maximum attachment of three molecules per hexagonal ring. Pressure and temperature are the main deciding parameters for the overall storage capacity of hydrogen on a ZnO substrate. kMC simulations are performed to capture the stochastic behavior of surface dynamics of gas molecules. Adsorption energy and diffusion barrier are predicted to be around 50–60 meV and 4–12 meV, respectively, according to vdW-DFT calculations. kMC simulations with these energy parameters estimate the surface coverage of hydrogen to be pretty high below room temperature and high pressure. Furthermore, the hydrogen adsorption in the ZnO monolayer leads to the increase of the bandgap value, subsequently changing the conductivity of the material. The present research work sheds light on the usage of a ZnO monolayer for suitable hydrogen gas storage and sensing applications. [ABSTRACT FROM AUTHOR]

Understanding the trapping and diffusion mechanism of hydrogen in vanadium carbide (VC) precipitates is crucial for exploring the issue of hydrogen embrittlement in steel. Although there is widespread consensus that VC can trap hydrogen, the mechanism by which hydrogen diffuses into VC is still unclear. In this study, we used first-principles calculation methods to study the influence of different spacings of carbon vacancies on the trapping and diffusion of hydrogen in VC. The increase in the number of C vacancies makes it easier for vacancies to trap hydrogen, and hydrogen tend to fill up C vacancies. The diffusion of hydrogen into VC only occurs via neighboring C vacancies at a distance of 0.295 nm (connecting vacancies), leading to a diffusion barrier of 0.63–0.78 eV. This is consistent with experimental results and validates the experimental speculation that the diffusion of hydrogen in VC requires a connecting C vacancy grid. [Display omitted] • Connectivity of C vacancies is crucial for hydrogen trapping in VC precipitates. • Diffusion barrier of hydrogen in VC is 0.63–0.78 eV, consistent with experiments. • Electron gas channels enable hydrogen diffusion through adjacent C vacancies. [ABSTRACT FROM AUTHOR]

Lattice engineering is reported to enhance Zn2+ storage capability of MnO via anionic doping, which effectively lowers the Zn2+ diffusion barrier and boosts Zn2+ diffusion kinetics. The optimized MnOS0.3@rGO exhibits superior rate capability and reversible capacity of 115.1 mA h g−1 at 0.5 A g−1 for 350 cycles. [ABSTRACT FROM AUTHOR]

Developing cathode materials for aqueous zinc‐ion batteries (ZIBs) that offer high capacity, rapid charge–discharge rates, and prolonged cycle life remains a significant challenge. This study explores the use of zipper‐type Bi2O2Se nanoplates modified by selenium vacancy (Vse) modulation, which reduces electron scattering, enhances carrier mobility in [Bi2O2] conducting channels, and decreases coulombic interactions within electrostatic layers. The introduction of Se vacancies facilitates electron transfer from the host to [Bi2O2] channels and reduces scattering in the [Bi2O2] framework, thus improving carrier mobility. These Se‐poor Bi2O2Se nanoplates demonstrate a greater affinity for zinc ions, reduced diffusion barriers, and faster transport kinetics, which enable more efficient Zn‐ion insertion, tripling the electrochemical capacity, improving rate capabilities, and extending cycling life. Enhancements such as reinforced structural integrity and expanded interlayer spaces support a dual Zn‐ion‐driven mechanism involving both insertion and conversion reactions, essential for superior electrochemical storage performance. The results include an impressive discharge/charge capacity of 380.3 mA h g−1 at 0.1 A g−1, a cycle life of up to 10 000 cycles at 5 A g−1, and a current tolerance exceeding 10 A g−1. This research highlights how nano‐ and defect engineering of Bi2O2Se can significantly enhance ionic conductivity, expedite electron transfer, and improve Zn‐ion diffusion. [ABSTRACT FROM AUTHOR]

Magnesium‐based batteries have garnered significant attention due to their high energy density, excellent intrinsic safety, and low cost. However, the application process has been hindered by the high Mg2+ ions diffusion barrier in solid‐state structures and solid‐liquid interphase. To address this issue, a hybrid battery technology based on Mg anode and Fe‐based Prussian Blue Analogue cathode doped with functional transition metal ions and N═O bonds is proposed. Combined multiscale experimental characterizations with theoretical calculations, the subtle lattice distortion can create an asymmetric diffusion path for the active ions, which enables reversible extraction with significantly reduced diffusion barriers achieved by synergistic doping. The optimized cathode exhibits a working potential of 2.3 V and an initial discharge capacity of 152 mAh g−1 at 50 mA g−1. With the preferred electrolyte combined with equivalent concentration [Mg2(µ‐Cl)2(DME)4][AlCl4]2 and NaTFSI salt solution, the hybrid system demonstrates superior cycling performance over 200 cycles at a high current density of 200 mA g−1, maintaining ≈100% coulombic efficiency with superior ion dynamic. The findings are expected to be marked an important step in the further application of high‐voltage cathodes for Mg‐based hybrid batteries. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have gained significant attention due to the abundant availability and low cost of sodium. However, the search for high-performance anode materials remains a critical challenge in advancing SIB technology. Based on first-principles swarm-intelligence structure calculations, we propose a metallic 1T′-MoSP monolayer as an anode material that offers a remarkably high storage capacity of 1011 mA h g−1, an ultralow barrier energy of 0.04 eV, and an optimal open-circuit voltage of 0.29 V, ensuring high rate performance and safety. Additionally, the monolayer presents favorable wettability with commonly used SIB electrolytes. Even after adsorbing three-layer Na atoms, the 1T′-MoSP monolayer retains its metallic nature, ensuring excellent electrical conductivity during the battery cycle. These desirable properties make the 1T′-MoSP monolayer a promising anode material for SIBs. [ABSTRACT FROM AUTHOR]

The development of high‐performance ion battery anode materials is conducive to the rapid development of urban rail transit. Based on first‐principles calculations, this paper studies the potential performance of the recently discovered two‐dimensional material SnSe2 as a negative electrode for zinc ion batteries. By calculating the adsorption energy, the most stable adsorption configuration of Zn was determined. The band gap of intrinsic SnSe2 decreases after strain, which promotes the transition of carriers. The band gap opens after the strain occurs in the Zn adsorbed SnSe2 system (Zn‐SnSe2), which confirms the regulation of strain on the band gap. The lowest diffusion barrier of Zn is 0.083 eV. The theoretical zinc storage capacity is calculated to be 387.550 mAh/g. The calculation results provide theoretical parameters for the application of SnSe2 in ion batteries. [ABSTRACT FROM AUTHOR]

The effects of thermal annealing on V‐based electrodes (V/Al/X/Au) with different diffusion barrier metal X are investigated for n‐type Al0.7Ga0.3N. At an annealing temperature of 800 °C, linear current (I)–voltage (V) characteristics are obtained, and the specific contact resistivities of the electrodes for X = Pt, Ni and V are 9.7 × 10−5, 2.3 × 10−4, and 1.8 × 10−4 Ω cm2, respectively. When the annealing temperature is increased to 850 °C, the I–V characteristics become nonlinear. Especially in the case of the V diffusion barrier, significant degradation of the ohmic contact is observed. The coverage of the electrode on the n‐type Al0.7Ga0.3N surface is significantly reduced after thermal annealing at 850 °C, resulting in a decrease in the current value. Furthermore, the formation of V–Al–Au and Al–Au alloys and diffusion of Au to the interface between the n‐type Al0.7Ga0.3N and electrode are found. The Au diffusion preferentially occurs through the domain boundaries of the alloys and causes the deterioration of the ohmic contact properties. In contrast, from the viewpoint of miscibility, Pt and Ni diffusion barriers are more effective than V in suppressing the formation of alloys with Au and then the diffusion of Au. [ABSTRACT FROM AUTHOR]

Metal ion intercalation into van der Waals gaps of layered materials is vital for large-scale electrochemical energy storage. Transition-metal sulfides, ABS4 (where A and B represent Zr, Hf, and Ti as monolayers as anodes), are examined as lithium and sodium ion storage. Our study reveals that these monolayers offer exceptional performance for ion storage. The low diffusion barriers enable efficient lithium bonding and rapid separation while all ABS4 phases remain semiconducting before lithiation and transition to metallic states, ensuring excellent electrical conductivity. Notably, the monolayers demonstrate impressive ion capacities: 1639, 1202, and 1119 mAh/g for Li-ions, and 1093, 801, and 671 mAh/g for Na-ions in ZrTiS4, HfTiS4, and HfZrS4, respectively. Average voltages are 1.16 V, 0.9 V, and 0.94 V for Li-ions and 1.17 V, 1.02 V, and 0.94 V for Na-ions across these materials. Additionally, low migration energy barriers of 0.231 eV, 0.233 eV, and 0.238 eV for Li and 0.135 eV, 0.136 eV, and 0.147 eV for Na make ABS4 monolayers highly attractive for battery applications. These findings underscore the potential of monolayer ABS4 as a superior electrode material, combining high adsorption energy, low diffusion barriers, low voltage, high specific capacity, and outstanding electrical conductivity. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) and its two-dimensional derivative (2D-BP) have garnered significant attention as promising anode materials for electrochemical energy storage devices, including next-generation fast-charging batteries. However, the interactions between BP and light metal ions, as well as how these interactions influence BP's electronic properties, remain poorly understood. Here, we employed density functional theory (DFT) to investigate the effects of monovalent (Li+ and Na+) and divalent (Mg2+ and Ca2+) ions on the valence electronic structure of 2D-BP. Molecular orbital analysis revealed that the adsorption of divalent cations can significantly reduce the band gap, suggesting an enhancement in charge transfer rates. In contrast, the adsorption of monovalent cations had minimal impact on the band gap, suggesting the preservation of 2D-BP's intrinsic electrical properties. Energetic and charge analyses indicated that the extent of charge transfer primarily governs the ability of ions to modulate 2D-BP's electronic structure, especially under high-pressure conditions where ions are in close proximity to the 2D-BP surface. Moreover, charge polarization calculations revealed that, compared with monovalent cations, divalent cations induced greater polarization, disrupting the symmetry of the pristine 2D-BP and further influencing its electronic characteristics. These findings provide a molecular-level understanding of how ion interactions influence 2D-BP's electronic properties during ion-intercalation processes, where ions are in close proximity to the 2D-BP surface. Moreover, the calculated diffusion barrier results revealed the potential of 2D-BP as an effective anode material for lithium-ion, sodium-ion, and magnesium-ion batteries, though its performance may be limited for calcium-ion batteries. By extending our understanding of interactions between ions and 2D-BP, this work contributes to the design of efficient and reliable energy storage technologies, particularly for the next-generation fast-charging batteries. [ABSTRACT FROM AUTHOR]

Segmented thermoelectric (TE) legs are promising for improving heat‐electricity conversion efficiency, but their practical applications are still limited by the lack of cost‐effective interface‐connection technology. Here, an interface‐connection method for one‐step sintering of GeTe‐Bi2Te3 segmented TE legs is developed using mixtures of Al0.88Si0.12 and Ni (ASN) as diffusion barrier materials. Although the interface‐connection performance using Ni or Al0.88Si0.12 alone is poor, their mixtures can realize a compromise optimization of interface‐connection properties, simultaneously achieving a matched coefficient of thermal expansion, low contact resistivity, high shear strength, and high reliability. These robust interface‐connection properties can be attributed to the activation of the eutectic‐alloy Al0.88Si0.12 and the formation of appropriate reaction‐diffusion layers between ASN and GeTe/Bi2Te3 and between Al0.88Si0.12 and Ni in ASN. Finally, a remarkable energy conversion efficiency of ≈15.5% at a temperature difference of 449 K can be obtained in this segmented TE leg. Moreover, ASN can also be applied in fabricating n‐type PbTe‐Bi2Te3 segmented legs and multi‐pair TE devices, demonstrating the universality of this methodology. This work accelerates the development of robust, low‐cost, one‐step‐sintered segmented TE legs and promotes the use of eutectic alloys as "alloy glues" for advancing TE‐device connection technology. [ABSTRACT FROM AUTHOR]

High‐temperature oxidation (1050°C) of Sr.9(Zr.9Yb.05Y.05)O2.85 (SZYY) thermal barrier coatings (TBCs) by suspension plasma spraying (SPS) and growth behavior of thermally grown oxide (TGO) were investigated. When the TBCs were exposed to high temperature for a period of time (∼5 h), the BC oxidized and TGO inevitably formed between the bond coating (BC) and the ceramic top coating (TC). The high‐temperature oxidation behavior of the BC is generally manifested as the growth of TGO, which has four specific stages as follows: (1) formative oxidation stage (0‒10 h), (2) rapid oxidation stage (10‒50 h), (3) stable oxidation stage (50‒100 h), and (4) complex oxidation stage (100‒200 h). The main component of early TGO is α‐Al2O3. It has a very low oxygen ion diffusivity and provides an excellent diffusion barrier, which has a positive effect on preventing further BC oxidation. However, as the heat treatment time increased, the Al consumption and the formation of a CNS layer (NiO, Co3O4, and spinel) in the BC eventually led to coating failure. The working life of TBCs can be improved by improving the ceramic TC structure and the Al content of BC. SZYY‐TBCs have certain potential application value. [ABSTRACT FROM AUTHOR]

[Display omitted] • N doped carbon coating CoP hollow nanofibers was successfully fabricated. • Multifunctional materials N/C@CoP-HNFs are used for PIBs and Li-S batteries. • N/C@CoP-HNFs with unique structures show good performance in PIBs and Li-S batteries. • Phase variations of electrodes at different states are studied. • DFT are used to understand electrochemical properties at the atomic level. Herein, a composite of N -doped carbon coated phosphating cobalt hollow nanofibers (N/C@CoP-HNFs) was synthesized by electrospinning, phosphating, and carbon coating processes. When employed as multifunctional electrode materials for potassium-ion batteries (PIBs) and lithium-sulfur (Li-S) batteries, the N/C@CoP-HNFs demonstrated notable electrochemical properties. Specifically, it delivered an initial specific capacity of 420.4 mA h g−1 at a current density of 100 mA g−1, with a sustained capacity of 190.8 mA h g−1 after 200 cycles in PIBs, and a specific capacity of 1448 mA h g−1 at a current density of 0.5C in Li-S batteries, which is considered relatively high for these types of battery technology. This good performance may due to the combination of the carbon nitrogen layer and cobalt phosphide bilayer hollow tube structure, which is conducive to telescoping the diffusion length of ions and electrons and buffer volume variation, and effectively inhibits the shuttle effect. Density functional theory (DFT) calculations were also used to explore the energy storage mechanism of the material. The possible adsorption sites and corresponding adsorption energy of K+ were analyzed, and the advantages of the material were explored by calculating the diffusion barrier and state density. The theoretical simulations further validated the strong adsorption capability of CoP for polysulfides. This work is expected to provide new ideas for new energy storage materials. [ABSTRACT FROM AUTHOR]

Purpose: The reliability of solder joints is closely related to the growth of an intermetallic compound (IMC) layer between the lead-free solder and substrate interface. This paper aims to investigate the growth behavior of the interfacial IMC layer during isothermal aging at 125°C for Sn-3Ag-3Sb-xIn/Cu (x = 0, 1, 2, 3, 4, 5 Wt.%) solder joints with different In contents and commercial Sn-3Ag-0.5Cu/Cu solder joints. Design/methodology/approach: In this paper, Sn-3Ag-3Sb-xIn/Cu (x = 0, 1, 2, 3, 4, 5 Wt.%) and commercial Sn-3Ag-0.5Cu/Cu solder were prepared for bonding Cu substrate. Then these samples were subjected to isothermal aging for 0, 2, 8, 14, 25 and 45 days. Scanning electron microscopy and transmission electron microscopy were used to analyze the soldering interface reaction and the difference in IMC growth behavior during the isothermal aging process. Findings: When the concentration of In in the Sn-3Ag-3Sb-xIn/Cu solder joints exceeded 2 Wt.%, a substantial amount of InSb particles were produced. These particles acted as a diffusion barrier, impeding the growth of the IMC layer at the interface. The growth of the Cu3Sn layer during the aging process was strongly correlated with the presence of In. The growth rate of the Cu3Sn layer was significantly reduced when the In concentration exceeded 3 Wt.%. Originality/value: The addition of In promotes the formation of InSb particles in Sn-3Ag-3Sb-xIn/Cu solder joints. These particles limit the growth of the total IMC layer, while a higher In content also slows the growth of the Cu3Sn layer. This study is significant for designing alloy compositions for new high-reliability solders. [ABSTRACT FROM AUTHOR]

Single crystal perovskites have garnered significant attention as potential replacements for existing absorber layer materials. Despite the extensive investigations on their photoinduced charge‐carriers dynamics, most of the time‐resolved techniques focus on bulk properties, neglecting surface characteristic which plays a crucial role for their optoelectronic performance. Herein, 4D ultrafast scanning electron microscopy (4D‐USEM) is utilized to probing the photogenerated carrier transport at the first few nanometers, alongside density functional theory (DFT) to track both defect centers and ions migration. Two compositions of mixed cation are investigated: FA0.6MA0.4PbI3 and FA0.4MA0.6PbI3, interestingly, the former displays a longer lifetime compared to the latter due the presence of a higher surface‐defect centers. DFT calculations fully support that revealing samples with higher FA content have a lower energy barrier for iodide ions to migrate from the bulk to top layer, assisting in passivating surface vacancies, and a higher energy diffusion barrier to escape from surface to vacuum, resulting in fewer vacancies and longer‐lived hole–electron pairs. These findings manifest the influence of cation selection on charge carrier transport and formation of defects, and emphasize the importance of understanding ion migrations role in controlling surface vacancies to assist engineering high‐performance optoelectronic devices based on single crystal perovskites. [ABSTRACT FROM AUTHOR]

The electrochemical performances of lithium‐ion batteries (LIBs) will be significantly degraded under low‐temperature conditions, which restricts their wide application in cold environments. Herein, the low‐temperature transport kinetics of a novel Nb1.94Mo0.06O5@C nanocomposite anode is accelerated greatly via engineering the microstructure and NbO6 octahedron. The detailed crystallographic features are characterized by using synchrotron radiation, spherical electron microscope, and density functional theory simulation methods. Both experimental and simulation analysis suggest that Mo6+ preferentially replaces Nb5+ in the regular octahedral location and distorts the NbO6 octahedron, resulting in a widened c‐axis spacing and a lowered ion diffusion barrier. Coupled with the enhanced electronic conductivity derived from surface carbon layer, Nb1.94Mo0.06O5@C anode exhibits an enhanced charge transfer process, improved Li+ diffusion kinetics, pronounced pseudo‐capacitance process, and excellent low temperature capacity. Furthermore, in situ X‐ray diffraction and ex situ electron microscope elucidate that the structural evolution of Nb1.94Mo0.06O5@C is highly reversible, unveiling its excellent cycling stability. The full cell assembled with LiNi0.6Co0.2Mn0.2O2 cathode demonstrates excellent practicality. This study reveals the critical role of distorting NbO6 octahedron and expanding crystal spacing in facilitating rapid Li+ diffusion and enhancing charge storage performance of Nb2O5 at low temperatures. [ABSTRACT FROM AUTHOR]

The Gd-doped CeO 2 (GDC) diffusion barrier between the zirconia-based electrolyte and the LSCF-based cathode in a solid-oxide fuel cell (SOFC) is essential for preventing the formation of Sc 2 ZrO 3 as a secondary phase. However, the reaction between ceria and zirconia at high temperatures (>1300 °C) impedes the formation of a highly dense GDC layer. Herein, we present a cost-effective approach for fabricating a highly dense GDC diffusion barrier layer at lower sintering temperatures by filling the pores of the GDC skeleton using a gelatin or polyvinylpyrrolidone (PVP) solution as a chelating agent for GDC cations. We investigated the interaction between the cations and the chelating agent molecules and its effect on the diffusion barrier. In addition, the flow behavior of the pore-filling solution was evaluated to determine its penetrability. The proposed method yielded a pore-filled GDC (PF-GDC) interlayer with enhanced density at 1000 °C, a remarkable 250 °C below the conventional sintering temperature for a porous GDC interlayer. The effectiveness of the PF-GDC was investigated by analyzing the performance of electrolyte-supported cells (ESCs) and anode-supported cells (ASCs). On ASCs, the observed peak power density at 800 °C was enhanced 1.5-fold, from 1.91 W⋅cm−2 (porous GDC sintered at 1250 °C) to 2.61 W⋅cm−2 (PF-GDC sintered at 1200 °C). These findings highlight the potential for pore-filling methods to improve the performance of SOFCs. • Pore-filling as a novel and cost-effective approach for fabricating GDC interlayers. • Dense GDC interlayer achieved via pore-filling method sintered at 1000 °C. • SOFC with pore-filled GDC sintered at 1200 °C showed a 1.5-fold enhancement. • Remarkable peak power density of 1.08 W·cm-2 (ESC) and 2.61 W·cm-2 (ASC) at 800 °C. • Gelatin and PVP as GDC chelating agents to fabricate single-phase GDC interlayer. [ABSTRACT FROM AUTHOR]

Diabetic polyneuropathy (DPN) is a multifactorial disease associated not only with hyperglycaemia but also with circulatory disturbances such as hypertension. A close interaction between the immune system and hypertension is known. It remains unclear whether the inflammatory response is associated with hypertension in the pathology of human DPN. Autopsied patients were evaluated: 7 non‐diabetic patients (nDM), 11 non‐diabetic patients with hypertension (nDMHT), 6 patients with diabetes (DM) and 9 patients with hypertension and diabetes (DMHT). Intraepidermal nerve fibre density (IENFD) was examined by immunofluorescent staining. Dissected sural nerve (SNs) were morphometrically quantified. Dermal and endoneurial macrophage infiltration was evaluated by double immunostaining using anti‐CD68 and anti‐CD206 antibodies. IENFD was significantly decreased in DM compared to nDM (p < 0.05) and was further decreased in DMHT (p < 0.05). Myelinated nerve fibre density (MNFD) in the SN was significantly decreased in DM compared with nDM (p < 0.05) and further decreased in DMHT (p < 0.01 vs. DM). The infiltration of CD206−/CD68+ proinflammatory macrophages in the SN was significantly increased in DM compared to nDM (p < 0.05), whilst the number of CD206+/CD68+ anti‐inflammatory macrophages was decreased in DM (p < 0.05). Hypertension had no impact on macrophage infiltration. The ratio of CD206− and CD206+ macrophage was negatively correlated with MNFD (r = 0.42, p < 0.05) but not IENFD (r = 0.30, p = 0.09). Dermal CD206+ macrophage infiltration was similar amongst all groups. Diabetes complicated by hypertension significantly increased the total diffusion barrier thickness (p < 0.01 vs. DM). Total diffusion barrier thickness was inversely correlated with both IENFD (r = ‐0.59, p < 0.01) and MNFD (r =‐0.62, p < 0.01). Our results suggest that vascular factors and inflammation might be synergistically involved in pathological changes in human diabetic patients through different mechanisms. [ABSTRACT FROM AUTHOR]

The tantalum oxide film was fabricated using an anodization process in a 0.5M H 2 SO 4 electrolyte. The evolution and corrosion resistance mechanism of anodized film on the Ta surface has been investigated by experiments and theoretical calculations. The results indicate that the sample with an anodic oxidation voltage of 20V and an anodic oxidation time of 60 min (Ta 20-60) exhibits the thickest oxidation film, measuring 360.00 nm and comprising an outer porous layer and an inner dense layer. Ta 20-60 demonstrates the highest E corr value of 0.009 V and the lowest I corr value of 0.879 μA cm−2, with a minimal density of point defects at 1.24 × 1019 cm−3, which imparts superior corrosion resistance. The calculation result shows that the growth rate of Ta anodic oxidation film is controlled by the diffusion and migration of vacancy defects. The O atom passes through one bridge site from the tetrahedral gap to another tetrahedral gap (Path 1) on the complete (110) surface has a low diffusion barrier of 0.470 eV and the shortest diffusion path of 2.04 Å, which is the most favorable path for the diffusion of O atoms. This paper offers a fresh perspective on the corrosion resistance of tantalum while furnishing guidance for improving Ta oxide film performance. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO)‐based all‐solid‐state lithium metal batteries (ASSLMBs) are strongly hindered by the fast dendrite growth at the Li metal/electrolyte interface, especially under large rates. The above issue stems from the suboptimal interfacial chemistry and poor Li+ transport kinetics during cycling. Herein, a SnF2‐catalyzed lithiophilic‐lithiophobic gradient solid electrolyte interphase (SCG‐SEI) of LixSny/LiF‐Li2O is in situ formed. The superior ionic LiF‐Li2O rich upper layer (17.1 nm) possesses high interfacial energy and fast Li+ diffusion channels, wherein lithiophilic LixSny alloy layer (8.4 nm) could highly reduce the nucleation overpotential with lower diffusion barrier and promote rapid electron transportation for reversible Li+ plating/stripping. Simultaneously, the insoluble SnF2‐coordinated PEO promotes the rapid Li+ ion transport in the bulk phase. As a result, an over 46.7 and 3.5 times improvements for lifespan and critical current density of symmetrical cells are achieved, respectively. Furthermore, LiFePO4‐based ASSLMBs deliver a recorded cycling performance at 5 C (over 1000 cycles with a capacity retention of 80.0 %). More importantly, impressive electrochemical performances and safety tests with LiNi0.8Mn0.1Co0.1O2 and pouch cell with LiFePO4, even under extreme conditions (i.e. 100 °C), are also demonstrated, reconfirmed the importance of lithiophilic‐lithiophobic gradient interfacial chemistry in the design of high‐rate ASSLMBs for safety applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Through the variable substitution and separated variable methods, this study develops a two‐dimensional (2‐D) axisymmetric diffusion analytical solution for organic pollutants in a circular‐shaped cutoff wall (CCW) system for the first time, which can more precisely and reasonably simulate the diffusion behaviors in “circular‐shaped” vertical barriers. Then, the proposed analytical solution's reasonableness is verified by comparing it with an existing analytical solution and a corresponding finite‐difference solution. Meanwhile, the comparison suggests that this solution will degrade to a 2‐D diffusion analytical solution when the pollution source radius is large enough. Furthermore, the presented analytical solution can also be simplified to a one‐dimensional axisymmetric diffusion analytical solution, or to the axisymmetric diffusion analytical solutions in a single‐layered medium. These exact analytical solutions can not only be applied to study axisymmetric diffusion behaviors under specific scenarios, but also be used to validate other complex numerical models. Last, a case study is conducted to investigate the impacts of pollution source concentration distribution, CCW horizontal thickness, and defined equivalent diffusion coefficient on the barrier performance. Overall, the proposed analytical solutions and obtained diffusion laws in this study can provide guidance for the service effect assessment and the engineering design of cutoff walls. [ABSTRACT FROM AUTHOR]

In light of the extensive use of tungsten (W) in fusion experimental devices and the importance of hydrogen isotopes permeation, based on the first principle approaches we study the effects of W doping on the formation energies of intrinsic point defects, hydrogen interactions with such defects, and hydrogen diffusion in bulk of α-Al 2 O 3. Our investigation demonstrated that W doping enhances the formation of oxygen and aluminum vacancies (Vo and V Al) in α-Al 2 O 3. In W doping α-Al 2 O 3 , hydrogen primarily exists in the form of Ho− (hydrogenation of the bulk V O 3−) and Hi− (H interstitial) defects, while it hardly occupies V Al. Hydrogen is firmly trapped by Vo with a formation energy −3.35eV, and Hi− diffusion become extremely challenging because W doping significantly raises the Hi− diffusion barrier to 4.44 eV. Our findings indicate that W doping is beneficial for hydrogen permeation resistance in α-Al 2 O 3. • W doping in α-Al 2 O 3 promotes oxygen and aluminum vacancies (Vo and V Al). • Hydrogen is firmly trapped by Vo (formation energy: −3.35eV) and rarely occupies V Al. • Hydrogen exists as Hi− (H interstitial) and Ho− (hydrogenation of bulk V O 3−). • W doping increases the migration barrier for Hi− to 4.44 eV, significantly limiting hydrogen permeation in α-Al 2 O 3. [ABSTRACT FROM AUTHOR]

The notion of spontaneous and persistent energy generation from omnipresent atmospheric moisture presents an alluring prospect in the realm of next‐generation energy sources. Here, an ultra‐durable and all‐weather energy generator (UAEG) predicated on interface‐induced proton migration derived from enhanced proton dissociation by charge transfer and ion occupation is reported, which reduces the diffusion barrier of protons in chromatogram‐like mass transfer by avoiding the rebinding of dissociated protons with charged polyelectrolyte chains, thus leading to efficient and continuous proton migration through heterogeneously hygroscopic interface and delivering ultra‐durable direct‐current output. Deep insight into underlying mechanisms is demonstrated by theoretical calculations and in situ investigations toward molecular interactions and charge distribution. A UAEG unit with 4 cm2 in size can generate an impressive electric output (0.88 V and 37.58 µA) across extensive relative humidity (10–90%) and ambient temperature (−30–50 ˚C), capable of generating energy in all‐weather conditions (e.g., sunny, cloudy, overcast, and rainy) regardless of day and night. Importantly, it is the first time that a commercial electronic is continuously driven for over 200 days in all‐weather conditions just depending on ambient moisture. This work provides a novel perspective for the development of ultra‐durable and all‐weather moisture‐enabled energy generators. [ABSTRACT FROM AUTHOR]

An artificial built‐in electric field from phase heterojunction is constructed within sodium‐rich manganese‐based layer‐structured oxide O3‐Na[Ni0.3Mn0.55Cu0.1Ti0.05]O2@Na2MoO4 through shared oxygen atoms. The spinel Na2MoO4 phase behaves as a p‐type semiconductor, while the O3‐Na[Ni0.3Mn0.55Cu0.1Ti0.05]O2 phase functions as an n‐type semiconductor. It can efficiently reduce the diffusion barrier and enhance electron transport, which can adequately promote the interfacial desolvation ability and reduce bulk lattice strains. The formed spinel heterostructure with crystal structure stability can also enhance the interface Na+ diffusion and protect the electrode against moisture and carbon dioxide corrosion. Besides, the molybdenum introduction within the lattice bulk can enhance the bond covalency, fortifying lattice oxygen stability and restraining structural distortion effectively. The obtained cathode demonstrates a high up to 224.61 mAh g−1 discharge specific capacity at 0.1 C and a long cycle stability with a 60.44% capacity retention after 265 cycles at 0.5 C. This study illuminates the potential of Na‐rich Mn‐based oxide cathodes for high‐energy‐density sodium battery utilizations. [ABSTRACT FROM AUTHOR]

As a promising anode candidate for sodium-ion batteries (SIBs), tin-based oxides suffer from rapid capacity fading, greatly limiting their practical applications. Herein, we designed and synthesized three cobalt–tin oxide composites (CSOs), with different degrees of crystallinity by controlling the annealing temperature, to understand the effect of amorphous and crystalline structures on the Na+ storage behavior of tin-based alloy anodes. Theoretical calculations suggest that the amorphous CSO (CSO-A) presents the lowest binding energy with Na+ and the lowest diffusion barriers of Na+ in comparison with that of crystallinity samples (CSO-AC and CSO-C), indicating that the amorphous CSO is the most energetically favorable for Na insertion. Similarly, the experimental results suggest that CSO-A delivers the highest initial specific capacity; however, it presents the worst cycling stability and reversibility. CSO-C displays the best cycling stability but the lowest specific capacity. Interestingly, the CSO-AC sample with both amorphous and crystalline domains achieves the best comprehensive electrochemical performance. Quantitative analysis of the electrochemical process reveals that controlled crystallinity significantly impacts the microstructure and band gap of CSO, which will further affect the reversibility of the conversion reaction and the percent of pseudocapacitance contribution. Our work suggests that, for the alloy anode, rational regulation of crystallinity is a substantial approach to improve capacity retention. [ABSTRACT FROM AUTHOR]

Lithium (Li) is a promising anode material for all‐solid‐state Li metal batteries (ASSLMBs) due to its high energy density. However, the interface incompatibility of Li/solid electrolyte and uneven Li deposition induces the penetration of Li dendrites. Herein, a multifunctional rich‐LiF/Mg artificial solid electrolyte interphase (SEI) layer is constructed from a MgF2‐PVDF‐HFP film to passivate the Li anode and achieve effective inhibition of Li dendrites. Notably, the triggered LixMg alloys rivet the Li6PS5Cl (LPSCl) electrolyte and Li anode together well, producing satisfactory interface contact and reducing overpotential. The mechanism of LiF and LixMg alloys to enhance the stability of the Li/LPSCl interface is further elucidated by density functional theory (DFT). Moreover, the synergistic interaction of LiF with high interfacial energy and LixMg alloys with low diffusion barrier promotes uniform deposition of Li during plating/stripping and structural stability. Therefore, the modified Li‐symmetric cell exhibits ultra‐high critical current density (2.0 mA cm−2) and considerable cyclic stability (more than 1000 h at 0.5 mA cm−2). Remarkably, NCM//LPSCl//3% MgF2‐PVDF‐HFP@Li ASSLMBs exhibit considerable long‐term cycle stability (86.9% capacity retention after 100 cycles at 0.2 C). This work highlights the critical role of the intermediate passivating layer in mitigating side reactions and preventing Li penetration. [ABSTRACT FROM AUTHOR]

The strain can regulate the electronic properties of transition metal sulfides and enhance their application in ion battery electrode materials. In this article, the potential of single‐layer SnS2 as anode material for magnesium ion batteries under shear strain and torsional strain was studied by first‐principles calculation. The calculation of adsorption energy shows that the strain does not have a great influence on the structural stability. The band gap of SnS2 calculated by HSE06 is 2.210 eV. When Mg is on the surface of SnS2, the band gap of SnS2 drops to 0.113 eV, which shows quasi‐metallic properties. Both strains can regulate the band gap value of SnS2. The diffusion energy barrier of SnS2 after strain is significantly lower than that without strain. After torsion strain, the diffusion barrier of Mg ions on SnS2 is 0.11 eV. The research results provide a theoretical basis for the design of magnesium ion batteries. [ABSTRACT FROM AUTHOR]

Amorphous transparent SiCx:H and SiCxNy:H films are prepared at a temperature of 200 °C and a discharge power of 200 W in an inductively coupled RF plasma reactor using hexamethyldisilane vapors and additional argon and/or nitrogen gases. The influence of N2 flow rate on the morphology, chemical structure, elemental composition, transmittance, refractive index, contact angle, and film deposition rate is studied. Plasma components are determined by optical emission spectroscopy. It is shown by HRTEM and EDS mapping methods that the annealed Cu/SiCx:H/Si(100) sample has distinct substrate/film and film/copper layer interfaces, no Cu diffusion occurs, and that the SiCx:H the film can be considered as a promising diffusion barrier layer. Stability of the films during storage under ambient conditions is studied. The tendency of SiCxNy:H films to oxidize is revealed by EDS, IR spectroscopy, and XPS. [ABSTRACT FROM AUTHOR]

Metal‐ion batteries are in huge demand to cope with the increasing need for renewable energy, especially in automobiles. In this work, we apply first‐principle calculations to examine two‐dimensional beryllium carbide (2D‐Be2C) as a possible anode material for metal‐ion (Na and K) batteries. 2D‐Be2C is a semiconductor and becomes metallic by adsorbing metal ions. Negative adsorption energy indicates stable adsorption on the monolayer of Be2C. Alkali metal diffusion barrier and optimum path for minimum energy are studied within the framework of the climbing image nudged elastic band method. Here, six intermediate images are considered between the initial and final states. The lowest diffusion barriers for a single adsorbed Na and K atom are 0.016 and 0.026 eV, respectively. A maximum open circuit voltage of around 1 V is computed for K ions, whereas 0.5 V is for Na ions. Also, the maximum storage capacity of the Be2C monolayer is estimated at 1785 Ah/kg. [ABSTRACT FROM AUTHOR]

Chemical mechanical planarization (CMP) of metal components is an essential step in the fabrication of integrated circuits. Metal CMP is a complex process where strategically activated (electro)chemical reactions serve to structurally weaken the surface layers of the material being processed, and the resulting overburdens are removed under low-force abrasion. Understanding the tribo-electrochemical mechanisms of this process is crucial to successfully designing the consumable materials for advanced CMP slurries that are needed for the new technology nodes. Using a model CMP system involving copper (wiring material in interconnect structures) and molybdenum (a new diffusion barrier material for copper), the present work illustrates a tribo-electroanalytical scheme for studying various mechanistic details of metal CMP. Electroanalytical probes are employed both in the absence and in the presence of surface polishing to quantify the interplay between mechanical abrasion and chemical surface modification. Weakly alkaline slurry formulations are tested with variable concentrations of silica abrasives and a complexing agent, citric acid. The results serve to examine the link between material removal and tribo-corrosion and to identify the functions of the active slurry additives in governing the rates and selectivity of material removal for CMP. [ABSTRACT FROM AUTHOR]

The influence of Si interlayers on the microstructure of the films and boundaries and on the reflective characteristics of Ti/Ni multilayer mirrors has been studied using X‐ray reflectometry and diffractometry. We established that these Si interlayers perform different functions at different interfaces. An Si interlayer at an Ni‐on‐Ti interface acts as a diffusion barrier. An Si interlayer at a Ti‐on‐Ni interface mainly acts as a smoothing layer with a slight diffusion barrier effect. The largest increase in the reflectance, from 62 to 65.7%, at a wavelength of 1.54 Å, is observed when Si interlayers are deposited on both boundaries. The reason for the increase in reflectivity is the decrease in the widths of the transition layers from 6.5 Å on Ni and 7.5 Å on Ti, to 6.0 Å on Ni and 5.0 Å on Ti, respectively. Here, we explain this through the 'barrier' effect of Si interlayers, which results in less mixing of film materials at the interfaces. Data on the reflectance of Ni/Ti multilayer mirrors in the spectral range of the 'water window' at a wavelength of 27.4 Å are presented for the first time. The maximum reflectivity for an Ni/Ti multilayer mirror at a grazing angle of 7.2° was about 56%. [ABSTRACT FROM AUTHOR]

Herein, the operation of a GeSe ovonic threshold switch (OTS) is studied as a self‐selecting memory cell based on the polarity effect. From the observed operating current (Iop) dependence and area scaling behavior, the critical role of Joule heating in ensuring exceptionally large memory window in this material is confirmed. The underlying mechanism is further investigated by means of chemical analysis and is confirmed to be caused by polarity‐dependent atomic migration under high‐Iop regime, consistent with elemental segregation due to electronegativity contrast. More specifically, selective diffusion of Ge atoms through the TiN layer into negatively biased top electrode stack is observed. At the same time, there is no sign of a similar process for Se atoms under opposite voltage polarity. Based on these observations, a novel memory concept utilizing a selective diffusion barrier is proposed. Furthermore, under low‐Iop regime, no major composition change is observed, leaving room for alternative interpretation of the polarity effect under such conditions. Finally, it is demonstrated that functional GeSe OTS‐only memory is fabricated with atomic layer deposition, making it suitable for vertical 3D integration to enable low‐cost applications. [ABSTRACT FROM AUTHOR]

Rechargeable magnesium batteries (RMBs) have garnered considerable interest from researchers and industries owing to their abundant resources, cost‐effectiveness, impressive energy density, and safety features, positioning them as a compelling technology for sustainable energy. Chalcogenides, with their high electrochemical activity and low charge density, facilitate the diffusion and migration of Mg2+. "Soft" anionic lattices, such as S or Se, weaken the Coulombic attraction between the crystal structure and Mg2+, thereby promoting the accelerated diffusion and reversible intercalation of Mg2+. Consequently, they are highly regarded as promising cathode materials for RMBs. However, their real‐world implementation is hindered by challenges including low conductivity, formidable ion diffusion barriers, and insufficient cyclic stability. In this study, chalcogenides are categorized into intercalation‐ and conversion‐types based on the Mg2+ storage mechanism, providing a comprehensive examination and taxonomy of various modification approaches aimed at enhancing the electrochemical performance of chalcogenides. These approaches include intercalation engineering, phase engineering, defect engineering, doping effects, and nanostructure engineering. Furthermore, specific modification strategies for certain chalcogenide cathode materials are summarized and discussed. Finally, the key points of optimization strategies for chalcogenide cathode materials are summarized, along with the proposed future breakthrough directions. [ABSTRACT FROM AUTHOR]

The development of new crystal materials for sodium-ion batteries is considered one of the most exciting fields in solid-state electrochemistry. To search for new sodium-ion conductors, we selected more than 200 structures from the Inorganic Crystal Structure Database (version 2023/1), consisting of four, five, and six elements with several oxygen-anionic groups. After the selection of 45 unique structures through geometrical analysis with the periodic 1D, 2D, and 3D migration maps, we calculated diffusion barriers and the crystal chemical stability index for each within the bond valence site energy method. Thus, we selected 21 different compounds to determine the room-temperature ionic conductivity and obtained 7 substances that have conductivity greater than 10−5 S cm−1. Among these prospective conductors, we identified a new class of Na2Ln(MO4)(PO4) (Ln = Er, Y, Tb, Ho; M = Mo, W) compounds with the layered sodium diffusion, which were not previously considered as possible conductors. [ABSTRACT FROM AUTHOR]

Under salt stress, the root system is the first barrier in plant resistance. Endodermal suberin in plant roots can act as a diffusion barrier to effectively control ion uptake under abiotic stress. Soil biological interaction can affect plant root anatomic characters. In this study, the effects of earthworms (Eisenia foetida) and arbuscular mycorrhizal (AM) fungi (Funneliformis mosseae) on the maize root diffusion barrier in saline-alkali soil and the distribution characteristics of Na+ were investigated. Maize seedlings grown in soil amended with earthworms and AM fungus were measured, and FY088 fluorescence staining was used to locate the accumulation of suberin in the endodermis. Scanning electron microscopy–energy dispersive X-ray spectrometry (SEM‒EDS) scanning was used to analyze the distribution of Na+ in the cross-section of roots, and inductively coupled plasma-optical emission spectrometry (ICP-OES) was used to measure the mineral absorption of plants. The results showed that the total biomass of maize seedlings under salt stress increased by 70.4% with the amendment of earthworms and AM fungus, compared with the group without the amendment. Earthworms and AM fungus significantly changed the root anatomy of maize seedlings in saline-alkali soil increasing the accumulation of suberin layers in maize endodermis, effectively changing the distribution characteristics of Na+ in root cross-section, reducing the transfer of Na+ to stele, and increasing the K/Na ratio in roots and shoots by 59.8% and 73.3%, respectively. Our research showed that in saline-alkali soil, earthworms and AM fungus mediated root development and anatomical structure changes of maize, which was beneficial to maintain ion homeostasis of maize seedlings and improve root salt tolerance. This study provides new evidence for earthworm–mycorrhizal interaction to improve plant salt tolerance in saline-alkali soil. [ABSTRACT FROM AUTHOR]

With the rapid development of the advanced electronic packaging field, the requirements for the connection between solder and Cu substrate are becoming increasingly stringent. Currently, the commonly used Ni-P diffusion barrier layer in the industry lacks long-term reliability, and its resistivity is higher than that of other substrates. This paper introduces the highly conductive metal element W to modify the binary Ni-P coating and prepares a ternary Ni-W-P coating through electrodeposition to improve this situation. The key parameters for the electrodeposition of ternary Ni-W-P are determined. The isothermal aging reaction of Ni-W-P with Sn-Bi solder at 100 °C was studied, and the results showed that, compared to the conventional Ni-P coating, the Ni-W-P barrier coating with higher W content has a much longer lifespan as a barrier layer and exhibits significantly better electrical conductivity. Additionally, the reaction mechanism between Ni-W-P and the Sn-Bi solder is proposed. This research presents a promising advancement in the development of barrier layers for electronic packaging, potentially leading to more reliable and efficient electronic devices. Introducing tungsten into the Ni-P matrix not only extends the lifespan of the coating but also enhances its electrical performance, making it a valuable innovation for applications requiring high conductivity and durability. This study could guide further investigations into the application of ternary coatings in various electronic components, paving the way for improved designs and materials in the semiconductor industry. [ABSTRACT FROM AUTHOR]

Melting point depressants (MPDs) are required to lower the melting point of filler for brazing. In this study, Zr was used as the MPD, and powder filler was prepared by adjusting the Zr and Mo content referring to Thermo-Calc calculations. The prepared filler was used to braze a high-Mo Ni3Al-based single crystal superalloy, IC21, for 1200 °C/30 min. The effects of adjusting the Zr and Mo content on the microstructure and tensile properties of the joint were investigated. The increase in Zr content promotes the formation of Ni7Zr2 in the joint, leading to a decrease in the tensile strength of the joint. The increase in Mo content forms diffusion barriers between the BM and filler, resulting in an enhancement in the tensile strength of the joint. However, continued increases in Mo content leads to an increase in the P-topologically close packed phase, causing a decline in the tensile strength of the joint. When the Zr content was (11.8–12.2) wt.% and the Mo content was (7.3–7.7) wt.%, the tensile strength of the joint at 980 °C reached a maximum of 550 MPa. This study provides a potential direction for the design of brazing filler composition for high-Mo Ni3Al-based superalloys. [ABSTRACT FROM AUTHOR]

Developing high‐capacity and high‐rate anodes is significant to engineering sodium‐ion batteries with high energy density and high power density. Layered Na2Ti3O7 (NTO), with an open crystal structure, large theoretical capacity, and low working potential, is recognized as one of the prospective anodes for sodium storage. Nevertheless, it suffers from sluggish sodiation kinetics and low (micro)structure stability triggered by a high Na+ diffusion barrier and weak adhesion of [Ti3O7] slabs. Herein, the interlayered local structure of NTO is regulated to solve the above issues, in which parts of interlayered Na+ sites are substituted by H+ (Na2−xHxTi3O7 [NHTO]). Theoretical calculations prove that the NHTO offers lower activation energy for Na+ transports and low interlayer spacings with alleviated Na–Na repulsion and relatively flexible [Ti3O7] slabs to reduce fractural stress. In situ and ex situ characterizations of (micro)structure evolution reveal that NHTO goes through transformation between H‐rich and Na‐rich phases, resulting in high structure stability and microstructure integrity. The optimal NHTO anode delivers a high capacity of 190.6 mA h g−1 at 0.5 C after 300 cycles and a superior high‐rate stability of 90.6 mA h g−1 at 50 C over 10,000 cycles at room temperature. Besides, it offers a capacity of 50.3 mA h g−1 after 1800 cycles at a low temperature of −20°C and 195.7 mA h g−1 after 500 cycles at a high temperature of 40°C at 0.5 C. The developed topologically interlayered local structure regulation strategy would raise the prospect of designing high‐performance layered anodes. [ABSTRACT FROM AUTHOR]

The development of high‐performance low‐temperature lithium metal batteries (LMBs) is hindered by severe lithium dendrite growth and sluggish charge transfer, both of which can be effectively addressed by constructing a robust solid electrolyte interphase (SEI) with improved Li+ transport kinetics. Compared to the soft organic SEI layers, LiF‐rich SEI shows sufficient mechanical strength to impede lithium dendrite growth, however, its extremely low ionic conductivity (≈10−13 S cm−1) hinders Li+ transport kinetics at low temperatures. Herein, a quasi‐ionic liquid (QIL, [Li(15‐crown‐5)]NO3) additive with rich NO3− is developed by introducing 15‐crown‐5 into LiNO3, which induces the in situ formation of SEI with abundant Li3N. Impressively, this Li3N SEI exhibits superior lithium affinity and lower ionic diffusion barriers as learned from empirical and computational studies, suggesting that it may be powerful to conquer the sluggish Li+ kinetics at low temperature. With the assistance of QIL additive, Li/LiCoO2 cells with a high mass loading of 11.5 mg cm−2 demonstrate stable cycling for 250 cycles without any capacity decay at ‐20 °C. This work opens an emerging avenue to construct high‐performance low‐temperature LMBs by manipulating SEI composition. [ABSTRACT FROM AUTHOR]

Flexible regulation of local chemistry and band gap of perovskite quantum dots (PeQDs) is crucial for exploring their new functionalities and device applications. In this work, a strategy based on the combination of femtosecond (fs) laser‐irradiation and thermal treatment to effectively manipulate chemical composition and emitting wavelength of PeQDs in amorphous glass, is reported. The engineering of ultrafast laser‐induced thermal effect enables to induce in situ nucleation/growth of dual‐phase PeQDs within an individual glass matrix. By elevating heat‐treatment (HT) temperature, I− ions are driven to surmount the diffusion barrier into the PeQDs lattice, leading to a tunable emission wavelength ranging from 613 to 647 nm. Besides, it is verified that the temperature‐dependent diffusion rate of I− ions plays a pivotal role in affecting luminescent efficiency and color of the dual‐phase glass. Finally, fs laser direct writing of multi‐color patterns is presented, which provides a flexible method to develop new encryption/decryption technology for information security and anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Ultra‐thin 2D materials have great potential as electrodes for micro‐supercapacitors (MSCs) because of their facile ion transport channels. Here, a high‐precision controllable photonic‐synthesis strategy that provided 1 inch wafer‐scale ultra‐thin film arrays of alloyed WxMo2xSy with sulfur vacancies and expanded interlayer (13.2 Å, twice of 2H MoS2) is reported. This strategy regulates the nucleation and growth of transition metal dichalcogenides (TMDs) on the picosecond or even femtosecond scale, which induces Mo–W alloying, interlayer expansion, and sulfur loss. Therefore, the diffusion barrier of WxMo2xSy is reduced, with charge transfer and ion diffusion enhancing. The as‐prepared symmetric MSCs with the size of 100 × 100 µm2 achieve ultrahigh specific capacitance (242.57 mF cm−2 and 242567.83 F cm−3), and energy density (21.56 Wh cm−3 with power density of 485.13 W cm3). The established synthesis strategy fits numerous materials, which provides a universal method for the flexible synthesis of electrodes in microenergy devices. [ABSTRACT FROM AUTHOR]

All-solid-state lithium–sulfur batteries (ASSLSBs) have gained significant attention due to their high energy density and excellent safety characteristics. However, the practical application of these batteries is hindered by interfacial issues between the solid electrolyte and electrode. The instability of this interface during charge–discharge cycles arises from side effects of the electrolyte and anode, as well as poor solid–solid contact. In this study, we employ first principles calculations to analyze the chemical stability at the interface between the Li1/2La1/2TiO3 (LLTO) electrolyte and the Li anode, with a focus on strategies to address this issue and stabilize the cathode–electrolyte interface. We systematically investigate various physicochemical properties at the LLTO‖Li and LLTO‖LiIn2 interfaces, including electron conductivity, work function, chemical stability, and Li+ diffusion across the interface. Our findings demonstrate that LLTO‖LiIn2 exhibits enhanced long-term storage capabilities for ASSLSBs while reducing overall costs. Alloying lithium anodes with In atoms weakens electron injection into the electrolyte within the anode, thereby reducing chances of electrolyte reduction and improving charge–discharge performance. Additionally, a lower Li+ diffusion barrier is observed at the LLTO‖LiIn2 interface which promotes efficient Li+ transport. This work provides valuable theoretical insights for developing effective interface engineering strategies between electrolytes and anodes. [ABSTRACT FROM AUTHOR]