Transactions of Nonferrous Metals Society of China (中国有色金属学报)•2026•DOI: 10.1016/S1003-6326(26)67061-6
Bulk nanocrystalline Zn−3Cu−0.2Sr−xLi (x = 0, 0.2, 0.4 wt.%) alloys were fabricated via high-speed rolling (HSR) to address the insufficient mechanical performance of as-cast Zn alloys for biodegradable bone fixation. The HSR process introduced dense dislocations that supplied driving force for recrystallization. Li addition promoted the formation of ε and β phases, which provided abundant heterogeneous nucleation sites and a strong Zener pinning effect, facilitating recrystallized grain nucleation while restricting growth. The average grain size of the 0.4Li alloy was refined from 181.8 μm in the as-cast state to 50 nm after rolling. The rolled 0.4Li alloy achieved an ultimate tensile strength of 433.3 MPa, a yield strength of 382.2 MPa, and an elongation of 15.2%. Relative to the as-cast Li-free alloy, the rolled 0.4Li alloy exhibited a 173% increase in yield strength and a 591% improvement in elongation. Nanocrystalline strengthening was the dominant mechanism, contributing 70.4% to the total yield strength. The fracture mode of the 0.4Li alloy transitioned from brittle fracture in the as-cast condition to ductile fracture after rolling. The combination of alloying design and HSR offers a viable route to bulk nanocrystalline Zn alloys with superior mechanical performance for temporary bone fixation applications.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01943-6
Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes. However, their efficiency is hindered by the sluggish oxygen reduction reaction (ORR) and chloride-induced degradation over conventional catalysts. In this study, we proposed a universal synthetic strategy to construct heteroatom axially coordinated Fe–N4 single-atom seawater catalyst materials (Cl–Fe–N4 and S–Fe–N4). X-ray absorption spectroscopy confirmed their five-coordinated square pyramidal structure. Systematic evaluation of catalytic activities revealed that compared with S–Fe–N4, Cl–Fe–N4 exhibits smaller electrochemical active surface area and specific surface area, yet demonstrates higher limiting current density (5.8 mA cm−2). The assembled zinc-air batteries using Cl–Fe–N4 showed superior power density (187.7 mW cm−2 at 245.1 mA cm−2), indicating that Cl axial coordination more effectively enhances the intrinsic ORR activity. Moreover, Cl–Fe–N4 demonstrates stronger Cl− poisoning resistance in seawater environments. Chronoamperometry tests and zinc-air battery cycling performance evaluations confirmed its enhanced stability. Density functional theory calculations revealed that the introduction of heteroatoms in the axial direction regulates the electron center of Fe single atom, leading to more active reaction intermediates and increased electron density of Fe single sites, thereby enhancing the reduction in adsorbed intermediates and hence the overall ORR catalytic activity.
Journal of Central South University•2026•DOI: 10.1007/s11771-026-6261-y
To mitigate the detrimental effects of sulfur and enhance the enrichment efficiency of valuable elements in desulfurized diasporic bauxite, the effects of CaO dosage, caustic alkali concentration, reaction temperature and time on the digestion behavior of alumina, sulfur and gallium were illustrated, and the digestion thermodynamics and mechanism were also revealed. During the high-temperature Bayer process, alumina and gallium were digested synergistically, while pyrite was digested to S2− and SO42−. Appropriate CaO dosage promotes the digestion of alumina and gallium, and facilitates the precipitation of sulfur as calcium sulfoaluminate hydrate, effectively removing sulfur from the solution. Excess CaO leads to the formation of hydrogarnet, wherein Ga3+ incorporates into the crystal lattice by substituting for Al3+, reducing the digestion efficiency of gallium. Under the optimum conditions (CaO dosage of 3%, reaction temperature of 260 ℃, reaction time of 60 min, caustic alkali concentration of 260 g/L), the corresponding alumina and gallium digestion efficiencies reach 90.82% and 77.58%, respectively, with a significantly reduced sulfur concentration of 1.32 g/L in the solution. This work provides theoretical guidance for the efficient co-extraction of alumina and gallium from high-sulfur bauxite via the Bayer process.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01784-3
Nickel-based cathodes in aqueous nickel-zinc batteries typically suffer from sluggish reaction kinetics and limited energy density. In situ introduction of metal phosphides and rational construction of heterostructures can effectively promote electron/ion transport. However, the complex evolution of phosphidation and intractable phosphidizing degree greatly affect the composition of active phase, active sites, charge transfer rate, and ion adsorption strength of cathodes. Herein, the critical bimetallic phosphide layer (CBPL) is constructed on the NiCo-layered double hydroxide (NiCo-LDH) skeleton by a controllable anion-exchange strategy, yielding a novel nanohybrid cathode (NiCo-P1.0, 1.0 representing the mass ratio of Na2H2PO2 to NiCo-LDH). The high-conductivity CBPL with the inner NiCo-LDH forms extensive heterostructures, effectively regulating the electronic structure via charge transfer, thereby improving electrical conductivity. Remarkably, the CBPL exhibits unexpected electrochemical activity and synergizes with NiCo-LDH for electrode reactions, ultimately delivering extra energy. Benefiting from the bifunctional CBPL, NiCo-P1.0 delivers an optimal capacity of 286.64 mAh g−1 at 1C (1C = 289 mAh g−1) and superb rate performance (a capacity retention of 72.22% at 40C). The assembled NiCo-P1.0//Zn battery achieves ultrahigh energy/power density (503.62 Wh kg−1/18.62 kW kg−1, based on the mass loading of active material on the cathode), and the flexible quasi-solid-state pouch cell validates its practicality. This work demonstrates the superiority of bifunctional CBPL for surface modification, providing an effective and scalable compositing strategy in achieving high-performance cathodes for aqueous batteries.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25050011
As the development of single-junction solar cells reaches a bottleneck, tandem solar cells have emerged as a critical pathway to further enhance power conversion efficiency. Among them, monolithic perovskite/silicon heterojunction tandem solar cells are currently the fastest-growing technology, achieving the highest efficiencies at relatively low costs. The interconnecting layer, which connects the two sub-cells, plays a crucial role in tandem cell performance. It collects electrons and holes from the respective sub-cells and facilitates recombination and tunneling at the interface. Therefore, the properties of the interconnecting layer are pivotal to the overall device performance. In this work, we applied statistical analysis and machine learning algorithms to systematically analyze the interconnecting layer. A comprehensive dataset on interconnecting layer parameters was established, and predictive modeling was performed using Lasso linear regression, random forest, and multilayer perceptron (a type of neural network). The analysis revealed key feature importance for experimental parameters, providing valuable insights into the application of interconnecting layers in perovskite/silicon heterojunction tandem solar cells. The final optimized interconnecting layer can achieve a proof-of-concept efficiency of 38.17%, providing guidance and direction for the development of monolithic perovskite/silicon tandem solar cells.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.08.007
Fracability evaluation is critical for efficiently extracting deep shale gas using hydraulic fracturing to avoid blind drilling and fracking. However, existing fracability indices often fail to systematically consider the mechanical behavior of rocks at high temperatures and high pressures (HTHP), coupled with geostress distributions and heterogeneous reservoir characteristics. This critical omission limits their effectiveness in accurately identifying the optimal fracability sweet spots within deep reservoirs. In this work, a fracability evaluation model was proposed based on the combined weighting method, integrating the improved brittleness index, rock strength, geostresses and natural weakness characteristics. A fracability grading evaluation was carried out to determine the potential fracture characteristics corresponding to shales with different fracability levels. Additionally, the fracability index was used for field validation and applications. Results show that rock brittleness and fracability are not equivalent for deep reservoirs. The fracability index is closely related to the pay zones and actual gas production, with a correlation as high as 84%, implying that the proposed method has practical significance in both experimental and field applications. The above findings can provide theoretical guidance for the selection of fracturing candidates and the optimal design of fracturing in deep resource development.
China Foundry•2025•DOI: 10.1007/s41230-025-4070-9
Si-containing Mg alloys solidified at conventional rates often contain coarse and sharp Mg2Si phases, which can result in inferior material properties. In this study, Mg-6wt.% Si (Mg-6Si) alloy was prepared by wire arc additive manufacturing (WAAM), employing the gas tungsten arc welding technique with rapid cooling. The microstructures and mechanical properties of the WAAM alloy were investigated and compared with those of the as-cast samples produced using a metal mold. The results indicate that the WAAM Mg-6Si is harder and stronger than the as-cast samples. The microhardness of the WAAM Mg-6Si increases by 36.6% in comparison to that of as-cast Mg-6Si alloy. Furthermore, the average tensile strengths at room temperature and 150 °C increases by 63.4% and 21.3%, respectively. WAAM refines both the Mg2Si phase and the overall grains, resulting in a homogeneous morphology and improved mechanical properties. The granular Mg2Si phase, characterized by fine particles with a diffused distribution, shows a significant increase in concentration. The acicular Mg2Si phase is distributed along the grain boundaries, and its concentration significantly decreases. The average grain size of the Mg2Si phase is about 9.20 μm, about 5 times smaller. The refinement and distribution of the granular Mg2Si phase, as well as the reduction in the amount of needle-like Mg2Si particles, are the key factors for improving the mechanical properties of WAAM Mg-6Si alloy.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6094-0
High performance composite photocatalyst is a hotspot in the photocatalysis researches. In this study, a cutting-edge CeO2/rutile composite photocatalyst with tiny CeO2 concentration of 1.28 wt% was synthesized via a simple photocatalytic method. This as-obtained CeO2/rutile catalyst (CeO2/TiO2-1:1) exhibited an enhanced wastewater degradation and improved water splitting H2 evolution ability, with 95.83 % removal ratio for methylene blue (MB), 72.84% for tetracycline (TC) and 87.57 μmol/g H2 evolution capacity. Light irradiation and 2-coordinated oxygen vacancies (OV2C) on rutile surface promoted the Ce3+ adsorption on the rutile (110) facet as DFT results shown. The CeO2/rutile type-II heterojunction was evidenced to promote the migration of e−/h+ and generation of ·OH/·O2− and H2, which rapidly boosted the whole photocatalytic performance. This as-prepared CeO2/TiO2 photocatalyst can provide useful inspirations and new thoughts about the photosynthesis process, and offer a novel strategy for heterojunction photocatalysts preparation.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6078-0
Water is a critical factor affecting the mechanical properties of rocks, leading to their degradation. Understanding the creep mechanical behavior of deep roadway surrounding rock under the influence of underground water is of great significance. Compression and creep experiments on sandstone with varying water contents were conducted using a deep soft rock five-linked rheological experiment system. The experimental conditions, including water content (0%, 0.8%, 1.6%, 2.4% and 3.3%) and confining pressure (0, 6, 9 and 12 MPa), were determined based on pressure-free water absorption tests and in-situ stress measurements. The experimental results show that the compressive strength, creep failure stress, and dilatancy stress of sandstone decrease exponentially with increasing water content, while they increase exponentially with confining pressure. The ratio of lateral to axial instantaneous strain increases nearly linearly with the increase of stress, and the lateral creep strain characteristics of the sample are more significant than the axial ones. The duration of the attenuation creep stage of sandstone decreases with increasing water content and increases with increasing confining pressure. The lateral strain enters the steady-state creep stage before the axial strain, and the onset time of the accelerated creep stage of lateral strain under the failure stress is earlier than that of axial strain. The long-term strength of sandstone was determined based on the lateral steady-state creep rate curve, showing a negative exponential relationship with water content and a positive exponential relationship with confining pressure. A method for determining the long-term strength of rocks based on the ratio of lateral strain to axial strain (μc) is proposed, which is independent of water content. The research results provide a reliable theoretical basis for the analysis of the long-term stability of roadways under the influence of groundwater and the early prediction of creep failure.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3109-7
Utilizing coarse aggregates containing mining waste rock for backfilling addresses the strength requirements and reduces the expenses associated with binder and solid waste treatment. However, this type of material is prone to aggregate segregation, which can lead to uneven deformation and damage to the backfill. We employed an image-segmentation method that incorporated machine learning to analyze the distribution information of the aggregates on the splitting surface of the test blocks. The results revealed a nonlinear relationship between aggregate segregation and variations in solid concentration (SC) and cement/aggregate ratio (C/A). The SC of 81wt%–82wt% and C/A of 10.00wt%–12.50wt% reflect surges in fluid dynamics, friction effects, and shifts in their dominance. A uniaxial compression experiment, supplemented with additional strain gauges and digital image correlation technology, enabled us to analyze the mechanical properties and failure mechanism under the influence of aggregate segregation. It was found that the uniaxial compressive strength, ranging from 1.75 MPa to 12.65 MPa, is linearly related to both the SC and C/A, and exhibits no significant relationship with the degree of segregation in numerical terms. However, the degree of segregation affects the development trend of the elastic modulus to a certain extent, and a standard deviation of the aggregate area ratio of less than 1.63 clearly indicates a higher elastic modulus. In the pouring direction, the top area of the test block tended to form a macroscopic fracture surface earlier. By contrast, the compressibility of the bottom area was greater than that of the top area. The intensification of aggregate segregation widened the differences in the deformation and failure characteristics between the different areas. For samples with different uniformities, significant differences in local deformation ranging from 515.00 με to 1693.70 με were observed during the stable deformation stage. The extreme unevenness of the aggregate leads to rapid crack penetration in the sample, causing macroscopic tensile failure and resulting in premature structural failure.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3114-x
Digital modeling and autonomous control of the die forging process are significant challenges in realizing high-quality intelligent forging of components. Using the die forging of AA2014 aluminum alloy as a case study, a machine-learning-assisted method for digital modeling of the forging force and autonomous control in response to forging parameter disturbances was proposed. First, finite element simulations of the forging processes were conducted under varying friction factors, die temperatures, billet temperatures, and forging velocities, and the sample data, including process parameters and forging force under different forging strokes, were gathered. Prediction models for the forging force were established using the support vector regression algorithm. The prediction error of Ff, that is, the forging force required to fill the die cavity fully, was as low as 4.1%. To further improve the prediction accuracy of the model for the actual Ff, two rounds of iterative forging experiments were conducted using the Bayesian optimization algorithm, and the prediction error of Ff in the forging experiments was reduced from 6.0% to 1.5%. Finally, the prediction model of Ff combined with a genetic algorithm was used to establish an autonomous optimization strategy for the forging velocity at each stage of the forging stroke, when the billet and die temperatures were disturbed, which realized the autonomous control in response to disturbances. In cases of −20 or −40°C reductions in the die and billet temperatures, forging experiments conducted with the autonomous optimization strategy maintained the measured Ff around the target value of 180 t, with the relative error ranging from −1.3% to +3.1%. This work provides a reference for the study of digital modeling and autonomous optimization control of quality factors in the forging process.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01555-6
Atomically precise metal nanoclusters are an emerging type of nanomaterial which has diverse interfacial metal–ligand coordination motifs that can significantly affect their physicochemical properties and functionalities. Among that, Cu nanoclusters have been gaining continuous increasing research attentions, thanks to the low cost, diversified structures, and superior catalytic performance for various reactions. In this review, we first summarize the recent progress regarding the synthetic methods of atomically precise Cu nanoclusters and the coordination modes between Cu and several typical ligands and then discuss the catalytic applications of these Cu nanoclusters with some explicit examples to explain the atomical-level structure–performance relationship. Finally, the current challenges and future research perspectives with some critical thoughts are elaborated. We hope this review can not only provide a whole picture of the current advances regarding the synthesis and catalytic applications of atomically precise Cu nanoclusters, but also points out some future research visions in this rapidly booming field.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01564-5
Formamidinium lead bromide (FAPbBr3) perovskite nanocrystals (NCs) are promising for display and lighting due to their ultra-pure green emission. However, the thermal quenching will exacerbate their performance degradation in practical applications, which is a common issue for halide perovskites. Here, we reported the heat-resistant FAPbBr3 NCs prepared by a ligand-engineered room-temperature synthesis strategy. An aromatic amine, specifically β-phenylethylamine (PEA) or 3-fluorophenylethylamine (3-F-PEA), was incorporated as the short-chain ligand to expedite the crystallization rate and control the size distribution of FAPbBr3 NCs. Employing this ligand engineering approach, we synthesized high quality FAPbBr3 NCs with uniform grain size and reduced long-chain alkyl ligands, resulting in substantially suppressed thermal quenching and enhanced carrier transportation in the perovskite NCs films. Most notably, more than 90% of the room temperature PL intensity in the 3-F-PEA modified FAPbBr3 NCs film was preserved at 380 K. Consequently, we fabricated ultra-pure green EL devices with a room temperature external quantum efficiency (EQE) as high as 21.9% at the luminance of above 1,000 cd m−2, and demonstrated less than 10% loss in EQE at 343 K. This study introduces a novel room temperature method to synthesize efficient FAPbBr3 NCs with exceptional thermal stability, paving the way for advanced optoelectronic device applications.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01536-9
The incidence of large bone defects caused by traumatic injury is increasing worldwide, and the tissue regeneration process requires a long recovery time due to limited self-healing capability. Endogenous bioelectrical phenomena have been well recognized as critical biophysical factors in bone remodeling and regeneration. Inspired by bioelectricity, electrical stimulation has been widely considered an external intervention to induce the osteogenic lineage of cells and enhance the synthesis of the extracellular matrix, thereby accelerating bone regeneration. With ongoing advances in biomaterials and energy-harvesting techniques, electroactive biomaterials and self-powered systems have been considered biomimetic approaches to ensure functional recovery by recapitulating the natural electrophysiological microenvironment of healthy bone tissue. In this review, we first introduce the role of bioelectricity and the endogenous electric field in bone tissue and summarize different techniques to electrically stimulate cells and tissue. Next, we highlight the latest progress in exploring electroactive hybrid biomaterials as well as self-powered systems such as triboelectric and piezoelectric-based nanogenerators and photovoltaic cell-based devices and their implementation in bone tissue engineering. Finally, we emphasize the significance of simulating the target tissue’s electrophysiological microenvironment and propose the opportunities and challenges faced by electroactive hybrid biomaterials and self-powered bioelectronics for bone repair strategies.