Journal of Advanced Ceramics•2026•DOI: 10.26599/JAC.2026.9221340
Protonic ceramic fuel cells (PCFCs) offer efficient intermediate-temperature energy conversion but are constrained by the trade-off between insufficient electrode activity and limited operational durability. This work develops a Zn/Yb B-site codoping strategy combined with temperature-induced nanoparticle exsolution to construct a triple-conducting cathode. Cation-driven charge modulation enhances ionic diffusion and electronic conduction, while the exsolved secondary BaCoO3−δ phase increases active site density, optimizes interfacial charge transfer, and promotes oxygen reduction reaction (ORR) kinetics. Zn/Yb codoping redistributes local charge density, weakens metal–oxygen bonds, and reduces oxygen vacancy formation energy, promoting oxygen vacancy generation. The increased oxygen vacancy concentration facilitates surface oxygen activation and lattice hydration, enhancing oxygen-ion and proton transport. Enhanced d–p orbital hybridization improves electronic conductivity and accelerates charge transfer kinetics. Optimized alkaline–earth sites suppress carbonate formation, imparting excellent CO2 tolerance. The optimized cathode delivers a peak power density of 0.99 W·cm−2 at 600 °C and stable operation over 100 h, with a polarization resistance of 0.110 Ω·cm2 under 20% H2O-air. This work provides a novel strategy for optimizing activity, conductivity, and stability in PCFC cathodes.
Chinese Journal of Energetic Materials (含能材料)•2026•DOI: 10.11943/CJEM2026001
To improve rock fragmentation in open-pit deep-hole blasting, an in-hole layered column charge configuration was designed. Small-scale blasting tests on sandstone specimens were conducted under continuous and layered column charges to capture the failure process and final fragmentation. DEM-PBM coupled simulations visualized the dynamic fracture evolution and validated the experimental observations. Results show that under continuous charge, the top quarter of the specimen developed only a single blast-induced crack, splitting it into two parts, with horizontal fragment velocity of 2.0 m·s⁻¹ and a maximum block size of 9.0 cm. In contrast, layered charge produced multiple cracks in the top quarter, fragmenting it into smaller pieces, increasing horizontal velocity to 7.0 m·s⁻¹, and eliminating blocks larger than 5.0 cm. Simulations confirmed these trends, with maximum block size reduced from 8.8 cm to below 5.0 cm and velocity reaching 6.8 m·s⁻¹, closely matching experiments. Field trials in an open-pit coal mine overburden blasting demonstrated that layered charge reduced the boulder yield from 48.1% to 5.6%, significantly improving fragmentation. The findings confirm the practical effectiveness of in-hole layered column charge in enhancing rock breakage in deep-hole bench blasting.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01999-4
With the widespread application of lithium batteries in electric vehicles and energy storage systems, battery-related safety and reliability issues have become increasingly prominent. Conventional monitoring methods often struggle to address dynamic changes under complex operando. In recent years, flexible sensing technology has emerged as a promising solution for battery health monitoring due to its high adaptability and conformability to complex structures. Meanwhile, empowered by artificial intelligence (AI) for data analysis, the collected data enables efficient and accurate state assessment, offering robust support for accident prevention. Against this background, this paper first explores the integrated applications of flexible sensors in battery health monitoring and their unique advantages in addressing complex battery operating conditions, while analyzing the potential of AI in battery state analysis. Subsequently, it systematically reviews mainstream flexible sensing technologies (e.g., film sensors, thermocouples, and optical fiber sensors), elucidating their mechanisms for revealing intricate internal battery processes during operation. Finally, the paper discusses AI’s role in enhancing monitoring efficiency and accuracy, and envisions future research directions and application prospects. This work aims to provide technical references for the battery health monitoring field as well as promote the application of flexible sensing technologies in improving battery system safety and reliability.
Journal of Central South University•2026•DOI: 10.1007/s11771-026-6295-1
Affected by the depositional environment, coal seams in the weathered and oxidized zone and their overlying strata are characterized by developed fractures and poor self-stability, leading to difficulties in roadway and working face roof management. This paper analyzes the failure characteristics of coal-rock masses in this zone. Combined with model tests and numerical simulation methods, it investigates the stress distribution status, deformation-failure characteristics, and movement-fracture laws of the overlying strata in a fully mechanized top-coal caving working face. The results indicate: (1) Weathering and oxidation significantly degrade strength and increase plastic deformation in coal-rock masses; (2) Under mining-induced disturbance, overlying strata stress is released from the in-situ state and sharply reduced, forming stress concentration zones ahead of the coal wall and at face ends; (3) During mining, fractures propagating upwards from the coal wall trigger rib spalling and top-coal collapse, forming combined cantilever and articulated rock beam structures. The overlying strata sequentially undergo four deformation-failure stages: "bed separation, immediate roof fracture, main roof fracture, and high-level strata collapse". The research findings can provide a basis for the safe mining of fully mechanized top-coal caving faces in weathered and oxidized coal.
Journal of Central South University•2026•DOI: 10.1007/s11771-026-6231-4
Piezoelectric enhanced photocatalytic purification of polluted wastewater is currently one of the better strategies for environmental pollution control. This work proposes a novel and efficient approach for the purification of tetracycline hydrochloride (TC) wastewater via core-shell MoS2/ZnO heterojunction activated by peroxodisulfate (PDS), where the MoS2/ZnO heterojunction was fabricated via a hydrothermal route. By exploiting the intrinsic piezoelectric properties of both MoS2 and ZnO, the heterojunction generates an internal electric field that facilitates the separation of photogenerated electron-hole pairs, thereby accelerating the photocatalytic purification. Under the optimized conditions, the TC purification efficiency can reach 91.2% with the collaborative assistance of PDS activation, and the MoS2/ZnO heterojunction also exhibited excellent recyclability, maintaining a purification efficiency of 90.76% over five cycles. The MoS2/ZnO heterojunction demonstrated robust photocatalytic activity under visible-light irradiation and aeration, with the purification kinetics conforming to a pseudo-first-order model. And the purification pathways of TC were systematically investigated, and the dominant reactive oxygen species involved in the process were identified. This work elucidates the underlying piezoelectric-photocatalytic mechanism and provides a sustainable strategy for the efficient removal of antibiotic contaminants from aqueous environments, offering significant potential for practical environmental remediation applications.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01796-z
Over 950 billion (about 3.8 million tons) masks have been consumed in the last four years around the world to protect human beings from COVID-19 and air pollution. However, very few of these used masks are being recycled, with the majority of them being landfilled or incinerated. To address this issue, we propose a repurposing upcycling strategy by converting these polypropylene (PP)-based waste masks to high-performance thermally conductive nanocomposites (PP@G, where G refers to graphene) with exceptional electromagnetic interference shielding property. The PP@G is fabricated by loading tannic acid onto PP fibers via electrostatic self-assembling, followed by mixing with graphene nanoplatelets (GNPs). Because this strategy enables the GNPs to form efficient thermal and electrical conduction pathways along the PP fiber surface, the PP@G shows a high thermal conductivity of 87 W m⁻1 K⁻1 and exhibits an electromagnetic interference shielding effectiveness of 88 dB (1100 dB cm−1), making it potentially applicable for heat dissipation and electromagnetic shielding in advanced electronic devices. Life cycle assessment and techno-economic assessment results show that our repurposing strategy has significant advantages over existing methods in reducing environmental impacts and economic benefits. This strategy offers a facile and promising approach to upcycling/repurposing of fibrous waste plastics.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01720-5
The ability to control the electrode interfaces in an electrochemical energy storage system is essential for achieving the desired electrochemical performance. However, achieving this ability requires an in-depth understanding of the detailed interfacial nanostructures of the electrode under electrochemical operating conditions. In-situ transmission electron microscopy (TEM) is one of the most powerful techniques for revealing electrochemical energy storage mechanisms with high spatiotemporal resolution and high sensitivity in complex electrochemical environments. These attributes play a unique role in understanding how ion transport inside electrode nanomaterials and across interfaces under the dynamic conditions within working batteries. This review aims to gain an in-depth insight into the latest developments of in-situ TEM imaging techniques for probing the interfacial nanostructures of electrochemical energy storage systems, including atomic-scale structural imaging, strain field imaging, electron holography, and integrated differential phase contrast imaging. Significant examples will be described to highlight the fundamental understanding of atomic-scale and nanoscale mechanisms from employing state-of-the-art imaging techniques to visualize structural evolution, ionic valence state changes, and strain mapping, ion transport dynamics. The review concludes by providing a perspective discussion of future directions of the development and application of in-situ TEM techniques in the field of electrochemical energy storage systems.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01704-5
The development of flexible zinc-ion batteries (ZIBs) faces a three-way trade-off among the ionic conductivity, Zn2+ mobility, and the electrochemical stability of hydrogel electrolytes. To address this challenge, we designed a cationic hydrogel named PAPTMA to holistically improve the reversibility of ZIBs. The long cationic branch chains in the polymeric matrix construct express pathways for rapid Zn2+ transport through an ionic repulsion mechanism, achieving simultaneously high Zn2+ transference number (0.79) and high ionic conductivity (28.7 mS cm−1). Additionally, the reactivity of water in the PAPTMA hydrogels is significantly inhibited, thus possessing a strong resistance to parasitic reactions. Mechanical characterization further reveals the superior tensile and adhesion strength of PAPTMA. Leveraging these properties, symmetric batteries employing PAPTMA hydrogel deliver exceeding 6000 h of reversible cycling at 1 mA cm−2 and maintain stable operation for 1000 h with a discharge of depth of 71%. When applied in 4 × 4 cm2 pouch cells with MnO2 as the cathode material, the device demonstrates remarkable operational stability and mechanical robustness through 150 cycles. This work presents an eclectic strategy for designing advanced hydrogels that combine high ionic conductivity, enhanced Zn2+ mobility, and strong resistance to parasitic reactions, paving the way for long-lasting flexible ZIBs.
Nano-Micro Letters•2025•DOI: 10.1038/sino-451787
China's push to dominate wide-bandgap power semiconductors hinges on two fronts: scaling 8-inch 4H-SiC substrates to automotive-grade yields and commercializing ultra-wide-bandgap beta-Ga2O3 for grid-scale switches. This report dissects the physics and economics. For 8-inch conductive 4H-SiC, PVT growth at 2,400°C demands axial thermal gradients below 5°C/cm to suppress micropipe densities under 0.1 cm^-2, yet current Chinese boules (SICC, TankeBlue) achieve 0.3-0.5 cm^-2, yielding only 35-45% usable area versus 60% for Wolfspeed's 6-inch lines. Epitaxial BPD-to-TED conversion rates in domestic CVD reactors (Naura, CETC) lag at 85-90% versus >95% for Aixtron's G5 WW C2, directly impacting 1,200V MOSFET reliability—bipolar degradation from stacking faults can increase on-resistance by 15% after 1,000 hours. Meanwhile, beta-Ga2O3, grown via EFG, offers a Baliga figure of merit 3x SiC at 1/5th substrate cost, but its 0.23 W/m·K thermal conductivity cripples thermal management—a 10kV switch would need 3x the die area to dissipate heat. Pilot lines at Sanan and CETC report 2-inch beta-Ga2O3 substrates with 5N purity, but 4-inch remains elusive. The CAPEX arithmetic is brutal: an 8-inch SiC line costs $800M+ for 100k wafers/year, while Ga2O3 could halve that, yet no one has solved the thermal problem. This report quantifies the trade-offs and identifies where China's equipment ecosystem—Naura's epi-reactors, CETC's ion implantation—could tip the balance.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01662-y
The use of microneedles (MNs) has been established as an effective transdermal drug delivery strategy that has been extensively deployed for treating various diseases, including skin diseases. MNs can surpass the constraints of conventional drug delivery methods by their superior safety and efficacy through precise targeting, while simultaneously enabling painless delivery. Currently, MNs are increasingly used as carriers for drug delivery, with the loading of insoluble drugs to improve their treatment efficiency or combining with bioactive substances for the construction of an efficient drug delivery system to maximize the effects of bioactive substances. The methods used for preparation MNs are diverse, enabling them to meet the requirements of most applications. The emergence of MNs has addressed the shortcomings associated with insoluble drugs, expanded the applications of bioactive substances, and improved their use in clinical practice. This review summarizes current information on the application of MNs in a variety of skin diseases, such as psoriasis, vitiligo, alopecia, hypertrophic scarring, atopic dermatitis, melanoma, acne, and skin infections. The current clinical applications and future opportunities for MNs in the treatment of skin diseases are also discussed. Despite substantial progress in the clinical application of MNs as delivery vectors, issues such as low drug loading and poor mechanical strength during MNs preparation remain the main challenges. Therefore, clinical implementation of MNs-based therapies remains limited, highlighting key opportunities for future research.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-06-01)
The quest for sustainable energy storage solutions is more critical than ever, with the rise in global energy demand and the urgency of transition from fossil fuels to renewable sources. Carbon nanotubes (CNTs), with their exceptional electrical conductivity and structural integrity, are at the forefront of this endeavor, offering promising ways for the advance of electrochemical energy storage (EES) devices. This review provides an analysis of the synthesis, properties, and applications of CNTs in the context of EES. We explore the evolution of CNT synthesis methods, including arc discharge, laser ablation, and chemical vapor deposition, and highlight the recent developments in metal-organic framework-derived CNTs and a novel CNT aggregate with a three-dimensional ordered macroporous structure. We also examine the role of CNTs in improving the performance of various EES devices such as lithium-ion, lithium-metal, lithium-sulfur, sodium, and flexible batteries as well as supercapacitors. We underscore the challenges that remain, including the scalability of CNT synthesis and the integration of CNTs in electrode materials, and propose potential solutions and future research directions. The review presents a forward-looking perspective on the pivotal role of CNTs in shaping the future of sustainable EES technologies.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-02-08)
Hard carbon, known for its abundant resources, stable structure and high safety, has emerged as the most popular anode material for sodium-ion batteries (SIBs). Among various sources, coal-derived hard carbon has attracted extensive attention. In this work, N and S co-doped coal-based carbon material (NSPC1200) was synthesized through a combination of two-step carbonization process and heteroatom doping using long-flame coal as a carbon source, thiourea as a nitrogen and sulfur source, and NaCl as a template. The two-step carbonization process played a crucial role in adjusting the structure of carbon microcrystals and expanding the interlayer spacing. The N and S co-doping regulated the electronic structure of carbon materials, endowing more active sites. Additionally, the introduction of NaCl as a template contributed to the construction of pore structure, which facilitates better contact between electrodes and electrolytes, enabling more efficient transport of Na+ and electrons. Under the synergistic effect, NSPC1200 exhibited exceptional sodium storage capacity, reaching 314.2 mAh g−1 at 20 mA g−1. Furthermore, NSPC1200 demonstrated commendable cycling stability, maintaining a capacity of 224.4 mAh g−1 even after 200 cycles. This work successfully achieves the strategic tuning of the microstructure of coal-based carbon materials, ultimately obtaining hard carbon anode with excellent electrochemical performance.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-01-08)
The nitrate reduction reaction (NtRR) has been demonstrated to be a promising way for obtaining ammonia (NH3) by converting NO3− to NH3. Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostructured nanowires (Co3O4/GDY NWs) by a simple two-step process including the synthesis of Co3O4 NWs and the following growth of GDY using hexaethynylbenzene as the precursor at 110 °C for 10 h. Detailed scanning electron microscopy, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman characterization confirmed the synthesis of a Co3O4/GDY heterointerface with the formation of sp-C―Co bonds at the interface and incomplete charge transfer between GDY and Co, which provide a continuous supply of electrons for the catalytic reaction and ensure a rapid NtRR. Because of these advantages, Co3O4/GDY NWs had an excellent NtRR performance with a high NH3 yield rate (YNH3) of 0.78 mmol h−1 cm−2 and a Faraday efficiency (FE) of 92.45% at −1.05 V (vs. RHE). This work provides a general approach for synthesizing heterostructures that can drive high-performance ammonia production from wastewater under ambient conditions.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25020008
In this study, we present the fabrication of vertical SnO/β-Ga2O3 heterojunction diode (HJD) via radio frequency (RF) reactive magnetron sputtering. The valence and conduction band offsets between β-Ga2O3 and SnO are determined to be 2.65 and 0.75 eV, respectively, through X-ray photoelectron spectroscopy, showing a type-Ⅱ band alignment. Compared to its Schottky barrier diode (SBD) counterpart, the HJD presents a comparable specific ON-resistances (Ron,sp) of 2.8 mΩ·cm² and lower reverse leakage current (IR), leading to an enhanced reverse blocking characteristics with breakdown voltage (BV) of 1675 V and power figure of merit (PFOM) of 1.0 GW/cm². This demonstrates the high quality of the SnO/β-Ga2O3 heterojunction interface. Silvaco TCAD simulation further reveals that electric field crowding at the edge of anode for the SBD was greatly depressed by the introduction of SnO film, revealing the potential application of SnO/β-Ga2O3 heterojunction in the future β-Ga2O3-based power devices.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25040033
As artificial intelligence (AI) workloads escalate exponentially, ultra-thin, high-efficiency voltage regulator modules (VRMs) with exceptional power density become essential for backside-mounted configurations. High-density multiphase DC−DC converters are pivotal for implementing vertical power delivery (VPD) architectures in XPU platforms. Strategically positioning these converters beneath processors and maximizing spatial utilization enables core rail currents exceeding 2 kA while significantly reducing power distribution network (PDN) losses compared to conventional solutions. The VPD configuration elevates system-level energy efficiency with >100 W power saving per processor, yielding megawatt-scale savings in a datacenter that uses ~100 000 processors. The synergy of 48 V power conversion architectures and advanced packaging techniques enables the industry’s commitment to balancing computational demands with CO2 emission reduction and environmental sustainability. This paper discusses system architecture, layout geometry, and control strategies for multi-chip multi-phase DC−DC converters, comparing ring, chain, and net topologies, as well as independent and master-slave control schemes.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.05.008
In cold-region environments, where complex stresses and mining disturbances occur, rock masses are frequently segmented into discontinuous bodies by fractured structural planes, leading to anisotropic physical and mechanical properties. To explore the evolution of microcracks, degradation characteristics, and failure modes of fractured rocks in cold regions under the influence of freeze–thaw cycles, integrating laboratory experiments with the damage mechanics of freeze–thaw cycles. A numerical model for freeze–thaw cycle damage in rocks with various fracture dip angles was developed. The study revealed that the freeze–thaw expansion force generated during the pore water–ice phase transition is the primary driving factor behind freeze–thaw cycle damage. The initiation and propagation of microcracks and micropores, the detachment of matrix particles, and the loosening of clay mineral structures result in the transformation of the rock from a dense to a porous state, causing significant degradation in macroscopic mechanical properties. As freeze–thaw cycles increase, both the uniaxial compressive strength and the deformation modulus of the rock decrease significantly, with the failure mode gradually shifting from brittle instability to brittle-plastic or plastic failure. The findings of this study offer a practical approach to uncovering the mechanical response mechanisms between freeze–thaw damage in fractured rocks and structural planes.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6155-4
This paper presents the application of a novel AI-based approach, Neural Physics, to produce high-fidelity simulations of train aerodynamics. Neural Physics is built upon convolutional neural networks (CNNs), where the weights are explicitly determined by classical numerical discretisation schemes rather than by training. By leveraging the power of AI technology, this recent approach results in code that can run easily on GPUs and AI processors, achieving high computational speed without sacrificing accuracy. The approach uses an implicit large eddy simulation method based on a non-linear Petrov-Galerkin method to model the unresolved turbulence. Furthermore, for higher-order finite elements, the convolutional finite element method (ConvFEM) is used, which greatly simplifies the implementation of higher-order elements within the NN4DPEs approach. We demonstrate the capability of Neural Physics by simulating a freight Locomotive Class 66 and a partially loaded freight train operating in an open field environment with and without cross wind. This is the first time that ConvFEM has been applied to high-speed fluid flow problems in complex geometries. The results are validated against existing numerical results and experimental measurements, and show good agreement in terms of pressure and velocity distributions around the train body.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6120-2
This work investigated tribological behavior and corrosion resistance of laser cladding (LC) Ti50Nb15V15Zr5Cr5Al10 high-entropy alloy (HEA) coatings on Ti6Al4V substrates. Microstructural characterization illustrated that there was only body centered cubic phase in the HEA coating. Besides, the coatings of different laser power all exhibited obviously higher hardness than the substrate. It is illustrated that the microstructure of the HEA coatings is composed of body centered cubic phase, and the temperature gradient contributes to the distribution difference between the equiaxed and columnar grains. Meanwhile, the relationships between the tribological behavior, corrosion resistance and alloying elements have been illustrated. The HEA coating with 2200 W holds the best wear and corrosion resistance. During the friction process, there are many oxides formed at high temperatures, and adhesive wear contributes most to the wear mechanism of the coatings. The wear volumes of the HEA coatings are only 24.7% to 45.5% of that of the Ti6Al4V substrate. Due to the alloying elements like Cr and Al, there is dense passive film formed during the corrosion process, thereby leading to better corrosion resistance of the coatings. The corrosion rates of the HEA coatings with 2200 W and Ti6Al4V substrate are 5.34×10−3 mm/a and 2.69×10−2 mm/a, respectively.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6061-9
High-energy continuous wave (CW) lasers are mostly used in laser damage applications, but efficient laser ablation of transparent materials is challenging due to low optical absorption. Considering the potential of femtosecond (fs) laser-induced air filament for high-peak laser transmission over long distances, femtosecond (fs) laser-induced air filaments are combined with a millisecond (ms) laser to form an fs-ms CPL, enhancing the efficiency of sapphire ablation through synchronized spatial-temporal focusing. Experimental results show that ablation efficiency increases with the ms peak power and duty ratio. Excessive thermal stress leads to fragmentation of the sapphire when the ms duty ratio is over 30% at the peak power of 800 W, or when the peak power is over 500 W at a duty ratio of 100%. Also, the mechanism of high-efficiency damage is revealed through in-situ high-speed imaging. According to it, the ablation process went through 4 stages within 1.5 ms: defect-creating, melting and ablation, spattering, and fragmentation. Finally, the equivalent ablation efficiency of the fs-ms CPL is as high as 1.73×107 μm3/J, about 28 times higher compared to the fs laser only. The CPL damage method explored in this paper can provide theoretical guidance for efficient laser damage of transparent materials.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3116-8
The growing demand for Ni and Co in the new energy sector necessitates efficient extraction methods for limonitic laterite ores. This study demonstrated the effectiveness of sodium sulfate (Na2SO4) as an additive for enhancing the co-enrichment of Ni and Co during solid-state reduction. Na2SO4 promoted the formation of two distinct liquid phases, low-melting-point FeS–FeO–Fe and NaAlSiO4–NaFeSiO4, facilitating the migration and aggregation of Ni–Co–Fe alloy particles, leading to a high-grade alloy powder with 11.98wt% Ni and 0.88wt% Co and recoveries of 94.03% and 80.16%, respectively. Ni–Co–Fe particle growth was mainly driven by the FeS–FeO–Fe eutectic melt, aligned with a liquid-phase sintering mechanism. Pilot-scale rotary kiln experiments validated the industrial feasibility of this approach, which offers a promising solution for the sustainable extraction of these critical metals.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2988-3
The <001> orientation of the Goss texture aligned with the rolling direction is the most easily magnetized direction, effectively enhancing the magnetic properties of non-oriented silicon steel. In the present study, an ultra-thin high-silicon sheet of 0.2 mm with a strong Goss texture was successfully fabricated using a two-stage rolling method, achieving superior magnetic properties. The combination of suitable primary rolling reduction and intermediate annealing proved beneficial in promoting the formation of Goss texture. Electron back scatter diffraction (EBSD) was used to characterize micro-shear bands within deformed grains of secondary rolled sheets. Observations revealed that the recrystallized Goss nucleus originated from the Goss substructure of shear bands within deformed {111}<112> grains during the initial stages of recrystallization. The influence of stored energy and grain size on texture evolution was thoroughly investigated using quasi-in situ EBSD during recrystallization. In the initial stages, large deformed {111}<112> and near {111}<112> grains with high stored energy facilitated nucleation and growth of Goss and near-Goss grains within shear bands and reduced grain boundary nucleation. In the later stages, large deformed grains with low stored energy underwent a strain-induced grain boundary migration mechanism to nucleate. During the recrystallization, many recrystallized Goss and near-Goss grains clustered together, with Goss grains rotating towards near-Goss orientation. The resulting annealed ultra-thin 0.2 mm sheet with a pronounced Goss texture exhibited superior magnetic properties.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2967-8
This work focuses on the influence of Al content on the precipitation of nanoprecipitates, growth of prior austenite grains (PAGs), and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two experimental shipbuilding steels after being subjected to high-heat input welding at 400 kJ·cm−1. The base metals (BMs) of both steels contained three types of precipitates: Type I: cubic (Ti,Nb)(C,N), Type II: precipitate with cubic (Ti,Nb)(C,N) core and Nb-rich cap, and Type III: ellipsoidal Nb-rich precipitate. In the BM of 60Al and 160Al steels, the number densities of the precipitates were 11.37 × 105 and 13.88 × 105 mm−2, respectively. The 60Al and 160Al steel contained 38.12% and 6.39% Type III precipitates, respectively. The difference in the content of Type III precipitates in the 60Al steel reduced the pinning effect at the elevated temperature of the CGHAZ, which facilitated the growth of PAGs. The average PAG sizes in the CGHAZ of the 60Al and 160Al steels were 189.73 and 174.7 µm, respectively. In the 60Al steel, the low lattice mismatch among Cu2S, TiN, and γ-Al2O3 facilitated the precipitation of Cu2S and TiN onto γ-Al2O3 during welding, which decreased the number density of independently precipitated (Ti,Nb)(C,N) particles but increased that of γ-Al2O3–TiN–Cu2S particles. Thus, abnormally large PAGs formed in the CGHAZ of the 60Al steel, and they reached a maximum size of 1 mm. These PAGs greatly reduced the microstructural homogeneity and consequently decreased the impact toughness from 134 (0.016wt% Al) to 54 J (0.006wt% Al) at −40°C.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2963-z
The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel (Fe–0.10C–5Mn) was investigated during uniaxial tensile testing. In-situ observations under scanning electron microscopy, transmission electron microscopy, and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation mechanisms. These findings were discussed with the local strain measurements via digital image correlation. The results indicated that Lüders band formation in the steel was limited to 1.5% strain, which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite (RA), which led to localized stress concentrations and strain hardening and further retardation of yielding. The small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin–Le Chatelier effect. The volume fraction of RA gradually decreased from 26.8% to 8.2% prior to fracture. In the late deformation stage, fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01613-z
Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells. The functional groups can passivate undercoordinated ions to reduce nonradiative recombination losses. However, how these groups synergistically affect the enhancement beyond passivation is still unclear. Specifically, isomeric molecules with different substitution patterns or molecular shapes remain elusive in designing new organic additives. Here, we report two isomeric carbazolyl bisphosphonate additives, 2,7-CzBP and 3,6-CzBP. The isomerism effect on passivation and charge transport process was studied. The two molecules have similar passivation effects through multiple interactions, e.g., P=O···Pb, P=O···H–N and N–H···I. 2,7-CzBP can further bridge the perovskite crystallites to facilitates charge transport. Power conversion efficiencies (PCEs) of 25.88% and 21.04% were achieved for 0.09 cm2 devices and 14 cm2 modules after 2,7-CzBP treatment, respectively. The devices exhibited enhanced operational stability maintaining 95% of initial PCE after 1000 h of continuous maximum power point tracking. This study of isomerism effect hints at the importance of tuning substitution positions and molecular shapes for organic additives, which paves the way for innovation of next-generation multifunctional aromatic additives.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01574-3
The presence of SnZn-related defects in Cu2ZnSn(S,Se)4 (CZTSSe) absorber results in large irreversible energy loss and extra irreversible electron–hole non-radiative recombination, thus hindering the efficiency enhancement of CZTSSe devices. Although the incorporation of Ag in CZTSSe can effectively suppress the SnZn-related defects and significantly improve the resulting cell performance, an excellent efficiency has not been achieved to date primarily owing to the poor electrical-conductivity and the low carrier density of the CZTSSe film induced by Ag substitution. Herein, this study exquisitely devises an Ag/H co-doping strategy in CZTSSe absorber via Ag substitution programs followed by hydrogen-plasma treatment procedure to suppress SnZn defects for achieving efficient CZTSSe devices. In-depth investigation results demonstrate that the incorporation of H in Ag-based CZTSSe absorber is expected to improve the poor electrical-conductivity and the low carrier density caused by Ag substitution. Importantly, the C=O and O–H functional groups induced by hydrogen incorporation, serving as an electron donor, can interact with under-coordinated cations in CZTSSe material, effectively passivating the SnZn-related defects. Consequently, the incorporation of an appropriate amount of Ag/H in CZTSSe mitigates carrier non-radiative recombination, prolongs minority carrier lifetime, and thus yields a champion efficiency of 14.74%, showing its promising application in kesterite-based CZTSSe devices.