Transactions of Nonferrous Metals Society of China (中国有色金属学报)•2026•DOI: 10.1016/S1003-6326(26)67065-3
Polycrystalline LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes undergo intergranular cracking and structural collapse during extended cycling, limiting their commercial viability. This study reports single-crystalline NCM811 synthesized via a rapid ethanol–water solvothermal method. The solvothermal duration was varied, and the 60 min sample (NCM-60) exhibited optimal electrochemical performance. X-ray diffractometry confirmed an α-NaFeO2 structure with R-3m space group and high crystallinity. NCM-60 delivered a reversible capacity of 157.28 mA·h/g at 1C and a capacity retention of 55.06% after 200 cycles, significantly outperforming polycrystalline NCM (PC-NCM). Cross-sectional scanning electron microscopy revealed no apparent cracks in NCM-60 after 200 cycles, whereas PC-NCM exhibited severe intergranular fracture. The results demonstrate that shortening solvothermal time reduces precursor particle size and crystallinity, but 60 min yields the best balance. Pre-oxidation of the carbonate precursor before lithiation is recommended to mitigate CO2 evolution and lithium–nickel disorder during high-temperature sintering. This rapid solvothermal route offers a scalable pathway to single-crystal NCM811 with enhanced cycling stability and mechanical integrity.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2026•DOI: 10.1016/j.ijmst.2026.03.001
Conventional hydraulic fracturing is widely used for underground gas control in coal mines; however, in deep, soft coal seams, poor wettability and low mechanical strength can cause rapid energy release under gas pressure and mining-induced disturbances. These conditions increase the risk of coal and gas outbursts, complicate rapid outburst elimination, and pose serious threats to safe mine operations. In this study, SiO2 nanofluid solutions with varying acidity were prepared, and molecular dynamics simulations, contact angle measurements, Fourier transform infrared spectroscopy, nanoindentation tests, and three-dimensional super-depth microscopy were employed to systematically investigate the mechanisms by which acidic SiO2 nanofluids enhance the wettability and nanomechanical strength of soft coal seams. The results show that SiO2 nanoparticles act as bridging agents between water molecules and the coal matrix. In the high-mass fraction H2O/SiO2/coal system, the adsorption layer thickness increases from 15.44 Å in the pure water system to 20.51 Å. Acidic SiO2 nanofluids substantially reduce the coal-water contact angle; at pH 2, the contact angle decreases to 47.9°, representing a 43.86% reduction relative to raw coal. The total absorption peak area of oxygen-containing functional groups increased accordingly, promoting a transition of the coal surface from hydrophobic to hydrophilic. SiO2 nanofluids with varying acidity also induce pronounced changes in the mechanical properties of coal samples. Under mildly acidic conditions (pH 5), the elastic modulus and hardness increase by 17.880% and 18.794%, respectively, while the peak displacement and contact displacement decrease by 8.056% and 8.117%. Mild acidity promotes the formation of local micropores and facilitates the embedding of SiO2 nanoparticles, enhancing structural support and improving nanomechanical performance. In contrast, under strong acidic conditions, the corrosion effect outweighs the supporting role of the nanoparticles, resulting in mechanical degradation. Overall, the synergistic effects of acidic environments and SiO2 nanofluids significantly influence the wettability and mechanical behavior of coal. By elucidating their combined modification mechanisms, this study provides theoretical support and new perspectives for fluid-injection enhancement and dynamic disaster prevention in deep, soft coal seams.
China Foundry•2026•DOI: 10.1007/s41230-026-5150-1
Optimizing the mechanical properties and fluidity of hypoeutectic Al-Si alloys in high-pressure die casting (HPDC) is critical for manufacturing thin-walled components with large sizes. The performance and fluidity of castings over long flow distances depend on the precise control of solidification behavior during the complex HPDC process. In this study, an AlSi10MnMg alloy was fabricated using a fluidity test mold with three channels of different thicknesses to investigate the influence of varying TiB2 content on the microstructure, mechanical properties, and fluidity of the alloy during long-distance filling in HPDC. Results indicate that the addition of 0.018wt.% TiB2 significantly reduces externally solidified crystals (ESCs) and porosity contents, improving the filling distance from 1,700 mm to 1,833 mm. The reduction in ESCs in the castings by TiB2 is attributed to its ability to promote the migration of ESCs from the shot sleeve toward the melt center, where temperature and flow velocity are higher. At a filling distance of 1,300 mm, the ultimate tensile strength (UTS), yield strength (YS), and elongation increase notably with addition of 0.018wt.% TiB2. When the addition of TiB2 increases to 0.036wt.%, the area fraction of ESCs in the channel increases compared to that with 0.018wt.%, and the filling distance slightly decreases to 1,796.9 mm. The mechanical properties of the alloy with 0.036wt.% TiB2 are better than those of the alloy with 0.018wt.% TiB2 over short distances, but become inferior beyond 1,000 mm. This work reveals the role of TiB2 in regulating solidification and flow during long-range filling, offering new insights into the processability of HPDC Al-Si alloys.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-02009-3
Stretchable electronics have been recognized as intriguing next-generation electronics that possess huge market value, and stretchable electronic conductors (SECs) are essential for stretchable electronics, which not only can serve as critical functional components but also are the indispensable electronic connections bridging various electronic components within stretchable electronic systems. Herein, we offer a comprehensive review of recent progress in SECs including the material categories, structure designs, fabrication techniques, and applications. The characteristics, performance enhancement strategies, and application requirements are emphasized. Based on the recent advances, the existing challenges and future prospects are outlined and discussed.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01941-8
MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development. MXene derivative, MBene, diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity, structural flexibility, and mechanical properties. This comprehensive review describes the sandwich-like structure of the synthesized MBene, derived from its multilayered parent material and its distinct chemical framework to date. The fields of focus encompass the investigation of novel MBenes, the study of phase-changing mechanisms, and the examination of hex-MBenes, ortho-MBenes, tetra-MBenes, tri-MBenes, and MXenes with identical transition metal components. A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage (Li/Na/Mg/Ca/Li–S batteries and supercapacitors), as well as conversion and harvesting (CO2 reduction, and nitrogen reduction reactions). The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes. This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01839-5
The emerging interfacial polarization strategy exhibits applicative potential in piezoelectric enhancement. However, there is an ongoing effort to address the inherent limitations arising from charge bridging phenomena and stochastic interface disorder that plague the improvement of piezoelectric performance. Here, we report a dual structure reinforced MXene/PVDF-TrFE piezoelectric composite, whose piezoelectricity is enhanced under the coupling effect of interfacial polarization and structural design. Synergistically, molecular dynamics simulations, density functional theory calculations and experimental validation revealed the details of interfacial interactions, which promotes the net spontaneous polarization of PVDF-TrFE from the 0.56 to 31.41 Debye. The oriented MXene distribution and porous structure not only tripled the piezoelectric response but also achieved an eightfold increase in sensitivity within the low-pressure region, along with demonstrating cyclic stability exceeding 20,000 cycles. The properties reinforcement originating from dual structure is elucidated through the finite element simulation and experimental validation. Attributed to the excellent piezoelectric response and deep learning algorithm, the sensor can effectively recognize the signals of artery pulse and finger flexion. Finally, a 3×3 sensor array is fabricated to monitor the pressure distribution wirelessly. This study provides an innovative methodology for reinforcing interfacial polarized piezoelectric materials and insight into structural designs.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01757-6
Bimodal pressure sensors capable of simultaneously detecting static and dynamic forces are essential to medical detection and bio-robotics. However, conventional pressure sensors typically integrate multiple operating mechanisms to achieve bimodal detection, leading to complex device architectures and challenges in signal decoupling. In this work, we address these limitations by leveraging the unique piezotronic effect of Y-ion-doped ZnO to develop a bimodal piezotronic sensor (BPS) with a simplified structure and enhanced sensitivity. Through a combination of finite element simulations and experimental validation, we demonstrate that the BPS can effectively monitor both dynamic and static forces, achieving an on/off ratio of 1029, a gauge factor of 23,439 and a static force response duration of up to 600 s, significantly outperforming the performance of conventional piezoelectric sensors. As a proof-of-concept, the BPS demonstrates the continuous monitoring of Achilles tendon behavior under mixed dynamic and static loading conditions. Aided by deep learning algorithms, the system achieves 96% accuracy in identifying Achilles tendon movement patterns, thus enabling warnings for dangerous movements. This work provides a viable strategy for bimodal force monitoring, highlighting its potential in wearable electronics.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01707-2
Harnessing solar energy to enhance the rechargeable zinc–air batteries (RZABs) performance is a promising avenue toward sustainable energy storage and conversion. Simultaneously enhancing light-absorption capacity and carrier separation efficiency in nanomaterials, as well as improving electrical conductivity and configuration for electrocatalysis, presents a formidable challenge due to inherent trade-offs and interdependencies. Here, we have developed a Janus dual-atom catalyst (JDAC) with bifunctional centers for efficient charge separation and electrocatalytic performance through a bipolar doping strategy. The in situ X-ray absorption near-edge structure and Raman spectroscopy analyses demonstrated that the Ni and Fe centers in JDAC not only function as effective sites for oxygen evolution reaction and oxygen reduction reaction, respectively, but also serve as efficient hole and electron enrichment sites, effectively suppressing photoelectron recombination while enhancing photocurrent generation. As a result, the assembled JDAC-based light-assisted RZABs exhibited extraordinary stability at large current densities. This work delivers pivotal insight to design Janus dual-atom catalysts that efficiently convert solar energy into electric and chemical energy.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-03-08)
Exploring cost-efficient and highly-efficient noble metal-free catalysts for the oxygen reduction reactions (ORRs) involved in sustainable energy devices remains a great challenge. Transition-metal phosphides supported on heteroatom-doped carbons have shown potential as alternative candidates for precious metals because of their tunable electronic structures and higher catalytic performance. Phosphating was used to construct CoP nanoparticles (NPs) anchored on a nitrogen-doped porous carbon framework (CoP@NC) from Co NPs loaded on NC, using PH3 gas released from NaH2PO2 during heat treatment. The dodecahedral structure of Co NPs was retained in their transformation to CoP NPs. The CoP@NC electrocatalyst shows a remarkable ORR activity with a half-wave potential up to 0.92 V under alkaline conditions, which is attributed to the combined coupling between the well dispersed CoP nanoparticles on the nitrogen-doped carbon and the efficient mass transport in the porous structure. Zinc-air batteries assembled with the CoP@NC electrocatalyst as a cathode have a high open-circuit voltage of 1.51 V and power density of 210.1 mW cm−2. This work provides a novel strategy to develop low-cost catalysts with an excellent ORR performance to promote their practical use in metal-air batteries.
Ship Mechanics (船舶力学)•2025•DOI: 10.3969/j.issn.1007-7294.2025.06.008
Mooring cable tension is a crucial parameter for evaluating the safety and reliability of a floating platform mooring system. The real-time mooring tension in an actual marine environment has always been essential data that mooring system designers aim to acquire. To address the need for long-term continuous monitoring of mooring tension in deep-sea marine environments, this paper presents a mooring cable tension monitoring method based on the principle of direct mechanical measurement. The developed tension monitoring sensors were installed and applied in the mooring system of the "Yongle" scientific experimental platform. Over the course of one year, a substantial amount of in-situ tension monitoring data was obtained. Under wave heights of up to 1.24 m, the mooring tension on the floating platform reached 16.5 tons. Through frequency domain and time domain analysis, the spectral characteristics of mooring tension, including wave-induced force, slow drift force, and mooring cable elastic restoring force, were determined. The mooring cable elastic restoring force frequency was approximately half of that of the wave signal. Due to the characteristics of the hinge connection structure of the dual module floating platform, under some specific working conditions the wave-induced force was the maximum of the three different frequency forces, and restoring force was the smallest.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6139-4
Water-rich cracks represent common tunnel defects. Intense pressure waves generated by trains traveling through tunnels may undergo enhancement within water-rich cracks. Using the re-normalization group (RNG) k-ε turbulence model and volume of fluid (VOF) method, this study analyzes the spatiotemporal distribution, spectral features, and influencing factors of pressure wave propagation in water-rich cracks when two high-speed trains intersect in a tunnel. The flow mechanisms underlying the pressure enhancement within water-rich cracks are also revealed. The main conclusions are as follows: 1) The positive and negative peak pressure coefficients in water-rich cracks are 1.34 and −2.36, with corresponding pressure gradient peaks of 31.41 kPa/s and −34.01 kPa/s. Compared to the tunnel wall, the peak pressure coefficients and gradients exhibit increases of 34.41%/44.63% and 31.61%/60.46%, respectively. 2) The dominant frequency of the pressure wave power spectral density (PSD) at the crack tip is 26.97% higher than that in the tunnel. The PSD peak value continuously increases with depth and is the largest at the crack tip, representing an increase of 9.36% compared to the tunnel. 3) An increase in crack width reduces the peaks of pressure waves, pressure gradients, and PSD, while increases in vertical and transverse depths amplify these peaks. Crack width has the most significant impact on pressure waves and pressure gradients, while transverse depth has the most significant effect on PSD peak values. 4) Driven by inertia and pressure differences, the water body oscillates variably, enhancing pressure fluctuation amplitude at the crack tip. The higher the water body's movement velocity, the greater the pressure gradient at the crack tip. The above research results may provide a reference for crack harnessing in high-speed railway tunnels.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6144-7
This paper aims to explore the influence of different noise barrier heights on the sound source generation mechanisms of higher-speed trains (400 km/h) using a combination of delayed detached eddy simulation (DDES) and Ffowcs Williams-Hawkings (FW-H) equations. Four cases are investigated and compared, i.e. 1) no barrier, 2) 2.3 m, 3) 3.3 m, and 4) 4.3 m single-side barriers on a bridge. Numerical results show that the presence of noise barriers causes an increase in sound source intensity ranging from 2.1 to 2.8 dB(A). However, the relationship between the barrier height and the increase in sound source intensity varies across different parts of the train. Compared with the head and front-middle cars, the boundary layer is thicker around the rear-middle and tail car areas. A thick boundary layer introduces the influence of the crash wall, causing asymmetry and increases in sound source intensity. This is due to the deceleration region formed between the crash wall and the rail surface, as well as the acceleration region formed by the contraction of the flow channel in the noise barrier, both of which influence the sound source's characteristics. In addition, higher barriers exacerbate asymmetry and increases in sound source intensity.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6151-8
A train body's cross-sectional shape has a significant impact on aerodynamic drag and operational safety in high-speed trains (HSTs). This study extracts five design variables from a real-world HST body: height, width, side arc radius, arc radius at the connection between the side and the roof, and arc radius at the connection between the side and the train's bottom. The cross-validated Kriging surrogate model and the genetic algorithm are used to perform two types of aerodynamic optimization, with the cross-sectional area as a constraint. Cross-sectional shapes are optimized in both windless and windy conditions. Numerical results indicate that in a windless environment, the aerodynamic drag coefficient of the whole train is reduced by 2.4%; in a windy condition, the aerodynamic drag coefficient of the entire vehicle is reduced by 2.4%, and the aerodynamic lateral force of the leading car is reduced by 37.8%. These suggest that a flat and wide shape helps to reduce not only overall aerodynamic drag in a windless environment but also aerodynamic load in a windy environment, which can be accomplished by reducing the area of the side wall and top region, lowering the train body's height, increasing its width, and lowering the radius of the side and top arcs.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6053-9
Transparent sand is a special material to realize visualization of concealed work in geotechnical engineering. To investigate the dynamic characteristics of transparent sand, a series of undrained cyclic simple shear tests were conducted on the saturated transparent sand composed of fused quartz and refractive index-matched oil mixture. The results reveal that an increase in the initial shear stress ratio significantly affects the shape of the hysteresis loop, particularly resulting in more pronounced asymmetrical accumulation. Factors such as lower relative density, higher cyclic stress ratios and higher initial shear stress ratio have been shown to accelerate cyclic deformation, cyclic pore water pressure and stiffness degradation. The cyclic liquefaction resistance curves decrease as the initial shear stress ratio increases or as relative density decreases. Booker model and power law function model were applied to predict the pore water pressure for transparent sand. Both models yielded excellent fits for their respective condition, indicating a similar dynamic liquefaction pattern to that of natural sands. Finally, transparent sand displays similar dynamic characteristics in terms of cyclic liquefaction resistance and Kα correction factor. These comparisons indicate that transparent sand can serve as an effective means to mimic many natural sands in dynamic model tests.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3088-8
Nickel-based single-crystal (SX) superalloys are the key metallic materials of aeroengines. However, thermomechanical deformation always occurs during the directional solidification of SX superalloys, negatively influencing the SX structure. Casting deformation is simulated in most of the previous studies, whereas the direct simulation of dendritic thermomechanical deformation has been largely ignored, resulting in a lack of comprehensive understanding of this process. In this study, we systematically investigate dendritic thermomechanical deformation with a model coupled with dendrite growth, fluid flow, and thermomechanical deformation behavior. Results reveal that the dendritic thermomechanical deformation-induced dendrite bending is not randomly distributed but is mainly concentrated on the casting surface. The dendritic thermal stress increases as dendrite grows and accumulates after dendrite bridging. Transverse thermal contraction mainly occurs at the edge of casting in the corner, and axial thermal contraction is larger than transverse contraction. The high-stress region of the primary dendrite trunk is mainly distributed below the dendrite bridging near the solidified part, and the stress along the transverse direction reaches its maximum value on the casting surface. Stress concentrated on the casting surface is mainly attributed to variations in transverse temperature gradients caused by heat dissipation on the lateral mold wall, and inconsistent constraints in the lateral mold walls.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3069-3
The rust layer is a critical factor in determining the corrosion resistance performance of weathering bridge steel. Understanding the evolution mechanism of this rust layer is fundamental for the design and optimization of such steel. This study investigates the evolution of the rust layer on high-Cr-content weathering bridge steel, using an atmospheric corrosion monitoring (ACM) sensor and big data mining techniques in a simulated tropical marine atmosphere. Results reveal that the protective properties of the rust layer follow a periodic pattern of “ascending–constant” rather than a continuous ascending. Correlation analysis indicates that this phenomenon is attributed to the introduction of Cr, which promotes the formation of FeCr2O4 in the rust layer. FeCr2O4 helps prevent chloride ions from penetrating the rust layer, exerting a protective effect. These findings provide a strong scientific foundation for the design and improvement of new high-Cr-content weathering bridge steels.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01495-1
Rechargeable magnesium batteries (RMBs) have been considered a promising “post lithium-ion battery” system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage market. However, the sluggish diffusion kinetics of bivalent Mg2+ in the host material, related to the strong Coulomb effect between Mg2+ and host anion lattices, hinders their further development toward practical applications. Defect engineering, regarded as an effective strategy to break through the slow migration puzzle, has been validated in various cathode materials for RMBs. In this review, we first thoroughly understand the intrinsic mechanism of Mg2+ diffusion in cathode materials, from which the key factors affecting ion diffusion are further presented. Then, the positive effects of purposely introduced defects, including vacancy and doping, and the corresponding strategies for introducing various defects are discussed. The applications of defect engineering in cathode materials for RMBs with advanced electrochemical properties are also summarized. Finally, the existing challenges and future perspectives of defect engineering in cathode materials for the overall high-performance RMBs are described.