Opto-Electronic Advances (光电进展)•2026•DOI: 10.29026/oea.2026.250197
Artificial compound eyes (CEs) remain inferior to insect counterparts in ommatidial spatial arrangement, size distribution, visual field adaptability, and environmental perception. This work presents a tunable bionic CE with coaxial lens-on-lens (LoL) ommatidia, inspired by Sympetrum frequens, integrating a flexible polydimethylsiloxane (PDMS) LoL array with a microfluidic chip to achieve simultaneous bi-focal imaging. The LoL array was fabricated via femtosecond laser dual-modification of quartz glass, two-step wet etching, and soft lithography, yielding a concave template of approximately 2.6 mm². Integration with a microfluidic chamber enabled liquid-pressure modulation of CE configurations, producing a complete curved bi-focal plane that overcomes the limitations of single-focal-plane and regionalized nonuniform ommatidia CEs. Optical characterization confirmed stable focusing performance for both large and small ommatidia within their theoretical fields of view (FOVs). Cooperative bi-focal imaging was achieved by regulating FOV and relative positions of different LoL ommatidia through controlled injection of PDMS precursor. Large-FOV imaging and moving target monitoring were demonstrated, with reconstructed trajectories of triangular and dragonfly targets in 3D coordinates. The tunable CE with LoL ommatidia offers significant potential for particle image velocimetry, robotic vision, and virtual endoscopy, providing a scalable route to advanced micro-optical systems with adaptive visual field and depth perception.
Nano Research•2026•DOI: 10.26599/FRICT.2026.9441262
The growing demand for high-performance and long-service components in challenging applications has driven the development of high-strength metastable β-titanium alloys with multifunctional surfaces. This study introduces a novel surface engineering strategy, integrated bulk heat treatment with surface functionalisation (IBTSF), which combines bulk aging treatment with catalytic ceramic conversion treatment (C3T) incorporating Ag or Au. This approach simultaneously imparts surface multifunctionalities—high hardness, desirable tribological properties, and high antibacterial efficacy—while enhancing bulk mechanical properties. Using the metastable β-titanium alloy Ti–15V–3Al–3Cr–3Sn (Ti–15–3) as a representative, C3T was catalysed with either Au or Ag. Under a 20 N load, Au-catalysed C3T achieved near-zero wear and a low, stable coefficient of friction (COF) of ~0.3, attributed to the formation of a lubricating tribo-film. In contrast, Ag-catalysed C3T maintained stable tribological performance up to 10 N while delivering high antibacterial efficacies of 99.878% and 99.999% against E. coli and S. aureus within 3–6 h of contact, respectively, through passive Ag-ion release. Both treatments enhanced bulk tensile strength by approximately 50%, from 872±39 to 1,280±40 MPa. This combination of exceptional wear resistance, potent antibacterial activity, and improved mechanical strength offers a promising pathway to surface multifunctionalising metastable alloys for long-service, high-reliability applications.
Nano-Micro Letters (纳微快报)•2026•DOI: 10.1007/s40820-025-01895-x
Co3S4 electrocatalysts with mixed valences of Co ions and excellent structural stability possess favorable oxygen evolution reaction (OER) activity, yet challenges remain in fabricating rechargeable lithium-oxygen batteries (LOBs) due to their poor OER performance, resulting from poor electrical conductivity and overly strong intermediate adsorption. In this work, fancy double heterojunctions on 1T/2H-MoS2@Co3S4 (1T/2H-MCS) were constructed derived from the charge donation from Co to Mo ions, thus inducing the phase transformation of MoS2 from 2H to 1T. The unique features of these double heterojunctions endow the 1T/2H-MCS with complementary catalysis during charging and discharging processes. It is worth noting that 1T-MoS2@Co3S4 could provide fast Co–S–Mo electron transport channels to promote ORR/OER kinetics, and 2H-MoS2@Co3S4 contributed to enabling moderate eg orbital occupancy when adsorbed with oxygen-containing intermediates. On the basis, the Li2O2 nucleation route was changed to solution and surface dual pathways, improving reversible deposition and decomposition kinetics. As a result, 1T/2H-MCS cathodes exhibit an improved electrocatalytic performance compared with those of Co3S4 and MoS2 cathodes. This innovative heterostructure design provides a reliable strategy to construct efficient transition metal sulfide catalysts by improving electrical conductivity and modulating adsorption toward oxygenated intermediates for LOBs.
Journal of Central South University•2026•DOI: 10.1007/s11771-026-6272-8
The development of coalbed methane in China is constrained by complex geological conditions characterized by low permeability, low saturation, low reservoir pressure, and high adsorption ("three lows and one high"), posing significant challenges to its efficient development. The liquid nitrogen-induced fracturing and permeability enhancement technology can effectively promote the expansion and connection of macroscopic and microscopic fractures, thereby improving the permeability of coal seams. In this study, industrial micro-CT scanning technology, the VRA-UNet method, and fractal dimension calculation methods are employed to conduct an in-depth analysis of the action mechanism of liquid nitrogen cold soaking on the fracture structure of coal bodies with different metamorphism degrees. The results indicate that liquid nitrogen cold soaking promotes the generation, expansion, and connection of new fractures inside coal bodies to form fracture networks. Via Matlab programming and VG Studio MAX image analysis software, fracture extraction and calculation are performed on CT-scanned coal samples; it is statistically found that the quantitative fracture indices of coal increase after liquid nitrogen cold soaking. Compared with the fracture spectrum peak proportions of raw coal samples, the fracture spectrum peak proportions of anthracite, bituminous coal, and lignite increase by 8.375%, 12.680%, and 79.939%, respectively after liquid nitrogen cold soaking. By combining the VRA-UNet method for coal fracture identification, the box-counting method is used to calculate that the fractal dimension of coal fractures after liquid nitrogen cold soaking is larger than that of raw coal samples. The research findings of this paper will provide theoretical and technical support for the efficient development of coalbed methane and the improvement of coal seam gas extraction rates.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01775-4
The hole transport layer (HTL)-free carbon-based perovskite solar cells (C-PSCs) are promising for commercialization owing to their excellent operational stability and simple fabrication process. However, the power conversion efficiencies (PCE) of C-PSCs are inferior to the metal electrode-based devices due to their open-circuit voltage (Voc) loss. Herein, time-resolved confocal photoluminescence microscopy reveals that grain boundary defects at the perovskite/carbon interface are very likely to function as nonradiative recombination centers in HTL-free C-PSCs. A versatile additive Li2CO3 is used to modify the conformal tin oxide electron transport layer for HTL-free C-PSCs. Li2CO3 modification can result in enhanced charge extraction and optimized energy alignment at electron transport layer/perovskite interface, as well as suppressed defects at perovskite top surface due to Li2CO3-induced formation of PbI2 crystallites. Such dual interfacial passivation ultimately leads to significantly improved Voc up to 1.142 V, which is comparable to the metal electrode-based devices with HTL. Moreover, a record-high PCE of 33.2% is achieved for Li2CO3-modified C-PSCs under weak light illumination conditions, demonstrating excellent indoor photovoltaic performance. This work provides a practical approach to fabricate low-cost, highly efficient carbon-based perovskite solar cells.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01763-8
All-inorganic perovskite materials exhibit exceptional thermal stability and promising candidates for tandem devices, while their application is still in the initial stage. Here, a metal halide doping strategy was implemented to enhance device performance and stability for inverted CsPbI3 perovskite solar cells (PSCs), which are ideal for integration into perovskite/silicon tandem solar cells. The lanthanide compound terbium chloride (TbCl3) was employed to improve buried interface between [4-(3,6-Dimethyl-9H-carbazol-9-yl) butyl] phosphonic acid (Me-4PACz) and perovskite layer, thereby enhancing the crystallinity of CsPbI3 films and passivating non-radiative recombination defects. Thus, the inverted CsPbI3 PSCs achieved an efficiency of 18.68% and demonstrated excellent stability against water and oxygen. Meanwhile, remarkable efficiencies of 29.40% and 25.44% were, respectively, achieved in four-terminal (4T) and two-terminal (2T) perovskite/silicon mechanically tandem devices, which are higher efficiencies among reported all-inorganic perovskite-based tandem solar cells. This study presents a novel approach for fabricating highly efficient and stable inverted all-inorganic PSCs and perovskite/silicon tandem solar cells.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-06-09)
During the operation of electronic devices, a considerable amount of heat and electromagnetic radiation is emitted. Therefore, the investigation of materials with electromagnetic shielding and thermal management abilities has significant importance. Hybrid materials of three-dimensional graphene networks containing both carbon nanotubes (CNTs) and SiC whiskers (3D graphene-CNT-SiC) were synthesized. Using an aqueous-phase reduction method for the self-assembly of the graphene oxide, a three-dimensional porous graphene structure was fabricated. SiC whiskers, inserted between the graphene layers, formed a framework for longitudinal thermal conduction, while CNTs attached to the SiC surface, created a dendritic structure that increased the bonding between the SiC whiskers and graphene, improving dielectric loss and thermal conductivity. It was found that the thermal conductivity of the hybrid material reached 123 W·m–1·K–1, with a shielding effectiveness of 29.3 dB when the SiC addition was 2%. This result indicates that 3D graphene-CNT-SiC has excellent thermal conductivity and electromagnetic shielding performance.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2026-41-01-03)
Standardization is necessary for the early industrialization of the new materials and technology. It is achieved by having agreed practices for the measurement of properties and other characteristics. The promising use of graphene-based materials in fields like electronics, energy, and composites has resulted in standards for their nomenclature, the measurement of key characteristics, and their specification, etc. Among these, standards for measuring the key characteristics are crucial. The critical parameters are the number of layers, the type and concentration of defects and functional groups, elemental composition, sheet resistance, and carrier mobility. Standards for characterizing these have been analyzed by the International Organization for Standardization Technical Committee in ISO/TC229 and the International Electrotechnical Commission Technical Committee in IEC/TC113. These give details of applicable or preferred samples, the fundamental principles of the techniques, specific precautions, and points for attention in the relevant standards. The pivotal role of the ISO/TC229 and IEC/TC113 standards is considered and challenges and future trends are outlined.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.07.012
Gob-side entry retaining (GER) is widely applied in China. Nevertheless, the stability mechanism of the GER with coal pillar-backfill body (CPBB) under dynamic overburden load remains unexplored. A voussoir beam structure (VBS) model is established to analyze roof structure stability during panel advancement, introducing a VBS stability criterion. Reducing block B length l and immediate roof damage variable D, and increasing coal pillar width xc, lowers the GER structure instability risk. Reducing l and the GER width w leads to a CPBB system stability upswing. A UDEC model was established to systematically reveal how the l, backfill body width xb, and strength affect the stability and coupling performance of the CPPB system by monitoring the crack damage DC. Simulation results indicate that at l=14 m, xb=2.0 m, water-cement ratio 1.5:1, the coal pillar and backfill body have similar DC but maintain stability, resulting in CPPB system coupling degree Ϗ, better. A novel GER method supported by the CPBB was implemented on-site. Monitoring results indicated that the coal pillar peak stresses were 19.17 MPa (ahead), 16.14 MPa (behind), and the backfill body peak stress was 12.27 MPa (maximum). The floor heave was 380 mm, with a 103 mm backfill body rib.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.07.003
The tensile strength of rocks under real-time high-temperatures is essential for enhanced geothermal system development. However, the complex occurrence and deep burial of hot dry rocks limit the quantity and quality of standard samples for mechanical testing. This paper compared the tensile strengths obtained from Brazilian splitting tests on standard samples (with a diameter of 50 mm and a thickness of 25 mm) and micro-tensile samples (with a diameter of 50 mm and a thickness of 25 mm) of two types of granites. A power-law size effect model was established between the two sets of data, validating the reliability of the testing method. Then, miniature Brazilian splitting under real-time high-temperature, combined with X-ray diffraction (XRD) revealed temperature-dependent strength variations and microstructural damage mechanisms. The results show that: (1) The comparison error between the tensile strength obtained by the fitting model and that of the measured standard samples was less than 6%. (2) In real-time high-temperature conditions, tensile strength of granite exhibited non-monotonic behavior, increasing below 300 °C before decreasing, with sharp declines at 400–500 °C and 600–700 °C. (3) Thermal damage stems from the differences in the high-temperature behavior of minerals, including dehydration, phase transformation, and differential expansion.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25080038
Neuromorphic devices have garnered significant attention as potential building blocks for energy-efficient hardware systems owing to their capacity to emulate the computational efficiency of the brain. In this regard, reservoir computing (RC) framework, which leverages straightforward training methods and efficient temporal signal processing, has emerged as a promising scheme. While various physical reservoir devices, including ferroelectric, optoelectronic, and memristor-based systems, have been demonstrated, many still face challenges related to compatibility with mainstream complementary metal oxide semiconductor (CMOS) integration processes. This study introduced a silicon-based Schottky barrier metal-oxide-semiconductor field effect transistor (SB-MOSFET), which was fabricated under low thermal budget and compatible with back-end-of-line (BEOL). The device demonstrated short-term memory characteristics, facilitated by the modulation of Schottky barriers and charge trapping. Utilizing these characteristics, a RC system for temporal data processing was constructed, and its performance was validated in a 5 × 4 digital classification task, achieving an accuracy exceeding 98% after 50 training epochs. Furthermore, the system successfully processed temporal signal in waveform classification and prediction tasks using time-division multiplexing. Overall, the SB-MOSFET's high compatibility with CMOS technology provides substantial advantages for large-scale integration, enabling the development of energy-efficient reservoir computing hardware.
China Foundry•2025•DOI: 10.1007/s41230-025-4118-x
In this study, carbon nanotubes (CNTs)/AlSi10Mg composite parts with CNTs contents ranging from 0.0 to 2.0wt.% were successfully fabricated via laser powder bed fusion (LPBF) with laser scan speeds ranging from 900 to 1,900 mm·s-1. Uniform dispersion of CNTs in the powders can be achieved when their content is below 2.0wt.%. In the LPBF samples, the morphology of the CNTs is found to be directly related to their content. Especially, the length of CNTs in samples prepared by LPBF increases as the CNT content increases. The length of CNTs is approximately 200-300 nm in the 1.0wt.% CNTs/AlSi10Mg composites and approximately 500-1,000 nm in the 2.0wt.% CNTs/AlSi10Mg composites. The hardness of the composites reaches its highest value of 143.3 HV when the CNTs content is 1.0wt.% and the laser scan speed is 1,300 mm·s-1. It is found that the self-lubricating properties of the CNTs improve the tribological properties of the composites. The coefficient of friction (CoF) and wear rate of the samples decrease with increasing CNT content. At a CNTs content of 2.0wt.%, the CoF and wear rate of the composite decrease by approximately 14% and 30%, respectively, compared to the unreinforced matrix. The presence of CNTs leads to a more complete and refined network microstructure within the samples. Both the CNTs and the aluminum carbide contribute to the Orowan mechanism and the Hall-Petch effect within the matrix.
China Foundry•2025•DOI: 10.1007/s41230-025-4041-1
The effect of melt superheating treatment on the solidification microstructure and mechanical properties of the γ' phase precipitation-strengthened K424 superalloy was investigated. Differential scanning calorimetry (DSC) experiments were conducted to explore the influence of melt treatment temperature on the undercooling of the superalloy. Additionally, pouring experiments were carried out to assess how alterations in both the temperature and duration of melt treatment impacted the grain size, secondary dendrite arm spacing (SDAS), elemental segregation, and mechanical properties of the alloy. Metallographic analysis, scanning electron microscopy, energy dispersive spectroscopy (EDS) and Thermo-Calc software were employed for microstructure characterization. The test specimens were subjected to tensile testing at room temperature and stress rupture testing at 975 °C under 196 MPa. The findings reveal that appropriate melt treatment conditions result in decreased grain size, refined SDAS, minimized elemental segregation, and significant improvements in mechanical properties. Specifically, the study demonstrates that a melt treatment at 1,650 °C for 5 min results in the smallest average grain size of 949 μm and the smallest SDAS of 25.38 μm. Furthermore, the room temperature tensile properties and creep resistance are notably affected by the melt treatment parameters. It is shown that specific melt treatment conditions, such as holding at 1,650 °C for 5 min, result in superior room temperature strength and extended stress rupture life of the K424 superalloy, while a balance between strength and stability is achieved at 1,600 °C with a holding time of 10 min. These findings offer guidance for optimizing the melt treatment parameters for the K424 superalloy, laying a foundation for further investigations.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01303-w
Lead zirconate titanate (PbZrxTi1-xO3, PZT) ferroelectric films possess remarkable characteristics such as high residual polarization, high dielectric constant, and high piezoelectric coefficient and have great application prospects in modern electronics, communications, medical care, and military fields. At present, the microstructure changes of PZT ferroelectric thin films have a significant impact on their electrical properties. Therefore, this work summarizes the influences of geometric structure (thickness, porosity), composition structure (Zr/Ti ratio, doping), and grain structure (grain size, grain boundaries, orientation) on the electrical properties of PZT ferroelectric thin films. The results show that the changes in thickness and porosity have a significant impact on the electrical properties of PZT ferroelectric films. Especially, the actual application scenarios and preparation processes determine the required geometric dimensions and structures of PZT ferroelectric films. The Zr/Ti ratio and doping mainly affect the electrical properties by influencing the phase composition of PZT ferroelectric films. The changes in grain size, boundary structure, and orientation dependence mainly have a certain degree of influence on the domain response and domain switching behavior of PZT ferroelectric thin films. In conclusion, different structures have different influence effects on the dielectric, ferroelectric, and piezoelectric properties of PZT ferroelectric films. The way the tiny structure affects how PZT thin films work was shown, helping to guide the design of ferroelectric thin film devices. In order to further study and apply piezoelectric ceramic devices, it is crucial to have an in-depth understanding of the relationship between the structure and performance of piezoelectric ceramic devices.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01314-7
As space equipment become larger in size and more flexible, generalized mechanisms are being widely used in space-deployable structures. Dynamic modeling of large-scale generalized space-deployable mechanisms is challenging owing to the coupling between the deformation of flexible links and rigid body motion. This study develops a dynamic modeling method for generalized mechanisms using the local frame of the SE(3) Lie group. The model represents both rigid and flexible links within a unified Lie group setting. The expressions for the velocities of rigid links and deformation of flexible links are derived using the Lie algebra framework. The nonuniqueness of the degrees of freedom of generalized kinematic pairs is considered, and the velocity fields of kinematic pairs in different situations are expressed. The equations of motion are derived using Hamilton’s principle. Because the velocities are expressed in the local frame, the mass matrix in the equation is constant, which yields a compact and unified expression for the dynamic equation. A Lie group generalized-α time integration method is adopted to ensure numerical stability and efficiency in simulating multibody systems with large rotations and deformations. Two numerical examples are studied to demonstrate a formulation that reflects the motion responses under varying configurations and loading conditions. This study broadens the application of the local frame of the Lie group formulation in space mechanisms and provides a new concept for dynamic modeling of generalized mechanisms.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-024-01172-9
Tracking control of tendon-driven manipulators has become a prevalent research area. However, the existence of flexible elastic tendons generates substantial residual vibrations, resulting in difficulties for trajectory tracking control of the manipulator. This paper proposes the radial basis function neural network adaptive hierarchical sliding mode control (RBFNNA-HSMC) method, which combines the dynamic model of the elastic tendon-driven manipulator (ETDM) with radial basis neural network adaptive control and hierarchical sliding mode control technology. The aim is to achieve trajectory tracking control of ETDM even under conditions of model inaccuracy and disturbance. The Lyapunov stability theory demonstrates the stability of the proposed RBFNNA-HSM controller. In order to assess the effectiveness and adaptability of the proposed control method, simulations and experiments were performed on a two-DOF ETDM. The RBFNNA-HSM method shows superior tracking accuracy compared to traditional model-based HSM control. The experiment shows that the maximum tracking error for ETDM double-joint trajectory tracking is below 2.593×10-3 rad and 1.624×10-3 rad, respectively.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3098-6
Along with the surging demand for energy storage devices, the cost and availability of the materials remain dominant factors in slowing down their industrial application. The repurposing of waste asphalt into high-performance electrode materials is of significant interest, as it holds the potential to circumvent energy and environmental issues. Here, we report the controllable synthesis of asphalt-derived mesoporous carbon as an active material for electrocatalytic hydrogen gas capacitor (EHGC). The hierarchically porous carbon (HPC) with a high surface area of 1943.4 m2·g−1 can operate in pH universal aqueous electrolytes in EHGC. It displays a specific energy and power density of 57 Wh·kg−1 and 554 W·kg−1 in neutral electrolyte as well as 52 Wh·kg−1 and 657 W·kg−1 in acidic electrolyte. Additionally, the charge storage mechanism of HPC–EHGC is studied with the help of Raman spectroscopy and X-ray photoelectron spectroscopy. Furthermore, the assembled HPC–EHGC device displays a discharge capacitance of 170 F·g−1 with an excellent capacitance retention rate of 100% up to 20000 cycles at 10 A·g−1 in acidic electrolyte. This work introduces a novel approach to converting waste asphalt into high-performance carbon for EHGC, achieving superior performance over commercial materials. By simultaneously addressing environmental waste issues and advancing energy storage technology, this study makes a significant contribution to sustainable materials science and next-generation battery development.
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.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2024•DOI: 10.1016/j.ijmst.2024.12.014
It is important to analyze the damage evolution process of surrounding rock under different water content for the stability of engineering rock mass. Based on digital speckle correlation (DSCM), acoustic emission (AE) and electromagnetic radiation (EMR), uniaxial hierarchical cyclic loading and unloading tests were carried out on sandstones with different fracture numbers under dry, natural and saturated water content, to explore the fracture propagation, failure precursor characteristics and damage response mechanism under the influence of water content effect. The results show that with the increase of water content, the peak stress and crack initiation stress decrease gradually, and the decreases are 15.28%–21.11% and 17.64%–23.04%, respectively. The peak strain and crack initiation strain increase gradually, and the increases are 19.85%–44.53% and 19.15%–41.94%, respectively. The precracked rock with different water content is mainly characterized by tensile failure at different loading stages. However, with the increase of water content, the proportion of shear cracks gradually increases, while acoustic emission events gradually decrease, the dissipative energy and energy storage limits of the rock under peak load gradually decrease, and the charge signal increases significantly, which is because the lubrication effect of water reduces the friction coefficient between crack surfaces.