Internal stress control is critical for the electroforming of high-precision components such as X-ray focusing mirrors, which typically require stress levels below 0.1 MPa to maintain shape accuracy. Meanwhile, the complex nonlinear interactions among multiple deposition parameters make stress optimization challenging using traditional methods. We propose a machine learning-assisted framework to systematically investigate and optimize the low-stress (< 0.1 MPa) electroforming of nickel and nickel-cobalt alloys from sulfamate baths. Among various machine learning algorithms, random forest is identified as the optimal predictive model. Based on this, a processing map correlating current density and cobalt concentration with low-stress conditions is established. SHAP analysis reveals that current density is the dominant factor, followed by cobalt concentration. Combined EBSD, XRD, and DFT calculations elucidate the underlying physical mechanisms. Current density induces grain refinement, while cobalt incorporation promotes solid solution formation, both of which lead to lattice expansion in the nickel structure and consequent tensile stress generation. Finally, finite element simulations guide the optimization of engineering solutions, leading to the successful fabrication of X-ray focusing mirrors with exceptional thickness uniformity (coefficient of variation < 2%)

Achieving simultaneously low coefficient of thermal expansion (CTE) and thermal conductivity (κ) is critical for the practical engineering implementation of rare-earth (RE) monosilicates in next-generation environmental barrier coatings. Herein, an Si-site doping strategy was proposed and validated in Yb2(Si0.7Ge0.3)O5. Dense and pure materials were prepared and their compositional homogeneity was confirmed by atomic-resolution EDS mapping. The material achieved a reduced CTE of 6.45 × 10–6 K-1 and low κ of 1.14 W·m-1·K-1 at 1400 °C, outperforming Yb2SiO5 and most RE-site doping monosilicates. The CTE reduction originates from Ge-induced local structure distortion in the [(Si,Ge)O4] tetrahedra, which enhances the deformation flexibility of tetrahedra unit and enabling more effective accommodation of thermally induced strain; the reduced κ is attributed to enhanced phonon scattering arising from the mass/size disorder and bonding heterogeneity within the [(Si,Ge)O4] tetrahedra. This work demonstrates Si-site doping as an innovative platform for tailoring the thermal behavior of RE silicates.

Constructing porous carbon adsorbents with SF6-matched ultramicropores is an effective route for recovering SF6 from nitrogen-rich gas streams. Herein, hemin was introduced into ZIF-8 precursors to regulate pyrolysis-induced pore evolution and produce Fe,N-containing porous carbons without corrosive KOH activation. The optimized Fe,N-C-1000 displayed a large BET surface area of 1772.60 m2 & sdot;g- 1 along with abundant ultramicropores mainly distributed at 0.5-0.65 nm, providing suitable confined spaces for adsorption of SF6. The Fe,N-C-1000 delivered an SF6 adsorption capacity of 4.58 mmol & sdot;g- 1 and an IAST selectivity of 222 at 298 K and 1.0 bar. Fixed-bed breakthrough tests verified the preferential retention of SF6 over N2, as well as good regenerability and cycling stability. Structure-performance analysis suggests that the improved separation performance is mainly governed by hemin-directed ultramicropore formation, while the Fe/N-containing surface environment contributes additionally to SF6 affinity. DFT calculations further support stronger SF6 interaction with the Fe,N-C model than with the undoped carbon model. These results demonstrate that hemin-assisted pyrolysis provides a feasible KOH-free strategy for constructing MOF-derived ultramicroporous carbons for the capture and recovery of SF6.

Conventional boron nitride (BN)-based composites are often limited by high porosity and long processing cycles, which severely restrict their mechanical performance and engineering applications. To overcome these limitations, a novel organic-inorganic hybrid matrix combined with a hot-compression orientation strategy is proposed. Liquid-phase polyborazylene (PBZ) was employed to promote the rearrangement and alignment of h-BN lamellae during pressing, and subsequent pyrolysis yielded a dense and continuous BN matrix with in situ precipitated nanocrystals serving as load-transfer nodes. This process significantly enhanced densification, reduced porosity, and enabled the construction of an ordered lamellar structure. Unlike conventional PIP processes that typically require similar to 10 repeated infiltration-pyrolysis cycles, this method achieves dense composites in a single pyrolysis step, effectively avoiding fiber damage and greatly shortening the fabrication cycle. The synergistic effects of aligned lamellae inducing extended crack propagation paths and in situ nanocrystals providing additional load-transfer mechanisms effectively improved the mechanical performance of the composites. The proposed PBZ-assisted hybrid matrix and lamellar-orientation design strategy offers a new and efficient route for developing high-performance BN-based composites with excellent wave-transmitting and thermal protection capabilities.

Carbon fiber (CF) holds promise for preparing thermal protection materials for extreme high-temperature applications. However, the performance of typical thermal protection materials composed of CF and ceramic coating remains inadequate mainly because of the low thermal conductivity and weak interfacial stability. Here, starting from the graphene fiber (GF) with thermal conductivity of similar to 1200 W m-1 K-1, we report highly thermally conductive and structurally stable graphene/titanium carbide fiber (GTF) with well-defined core-shell structure via a one-step molten salt synthesis approach. With an optimal shell thickness of 1 & micro;m, the single GTF exhibits a thermal conductivity of 745 W m-1 K-1 and excellent thermal shock resistance without interfacial failure, ensuring its durability for long-term service in extreme conditions. Moreover, GTF woven exhibits excellent ablation resistance. The mass ablation rate is as low as 0.3 mg s-1 after exposure to oxyhydrogen flame at 2200 degrees C. The excellent performance is attributed to the intrinsic high thermal conductivity of GF for rapid thermal dissipation and the full-scale fractal-like interlocking interfaces between the GF and carbide coating for sustaining local interface stress. This work paves the way for GF/ceramic composites as next-generation dredging thermal protection materials to satisfy extreme heat flux management and structural integrity.

The crystalline-amorphous (c-a) heterointerface represents an innovative approach that provides a transformative strategy to overcome the challenges associated with conventional catalyst configurations. By integrating the broad-range electronic conductivity and mechanical strength of crystalline phases with the coordinatively unsaturated sites and configurational entropy of amorphous domains, these hybrid heterostructures establish distinct interfacial regions that fundamentally modify adsorption energetics, reaction pathways, and durability under operating conditions. This review offers an in-depth and critical evaluation of the growing domain of c-a dense heterointerfaces in catalysis, emphasizing sustainable energy conversion processes such as the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), freshwater/seawater splitting, and small molecule synergistic electrolysis. We primarily highlight the core aspects (e.g., interfacial synergism, dynamic reconstruction and self-optimization, electronic configuration, balanced crystallinity and amorphicity) that regulate interfacial development, underscoring the underlying thermodynamic and kinetic principles that influence the efficiency of c-a heterojunctions. We proceed to assess the catalytic performance in major electrochemical and thermochemical reactions, establishing correlations that translate interfacial motifs into activity, selectivity, and stability attributes. Particular emphasis is placed on the mechanistic value of dense heterointerface engineering in regulating the overall electronic configuration, directing chemical intermediates, and offering remarkable resistance to corrosion and material dissociation. Finally, the challenges that confront the field and feasible opportunities to expedite the transition of c-a heterointerfaces from fundamental advancement to applicable catalytic technologies are presented. This study seeks to bring together existing knowledge and outline future trajectories, positioning c-a heterointerfaces as a robust and adaptable foundation for the forthcoming generation of high-performance catalysis.

Addressing the escalating global energy and environmental crises demands efficient, sustainable, and robust technologies. In this study, a ternary composite PCN/CdS/CdIn2S4 integrating phosphorus-doped carbon nitride (PCN), cadmium sulfide (CdS), and indium cadmium sulfide (CdIn2S4) was rationally designed via a multi-step assembly process. The optimized heterojunction exhibits outstanding performance, achieving remarkable H2 and H2O2 production rates of 7614 and 6873 μmol∙g−1 h−1, respectively. Additionally, it demonstrates ultra-fast degradation kinetics, mineralizing 99.4% of methyl orange within just 30 min. Mechanistically, spontaneous interfacial band bending drives a dual Z-scheme charge transfer pathway. This specific energy band alignment effectively preserves strongly reducing electrons and highly oxidizing holes while significantly suppressing charge carrier recombination. Furthermore, radical trapping confirms that superoxide radicals (∙O2−) are the pivotal active species, driving a two-step single-electron reduction pathway (O2→∙O2-→H2O2) for continuous H2O2 generation, and coupling synergistically with localized holes for rapid organic pollutant decomposition.

Electrodeposited nickel is widely used in high-precision manufacturing, where both crystallographic orientation and internal stress critically affect the mechanical performance and dimensional stability of coatings. However, achieving simultaneous control over crystallographic orientation and internal stress remains a significant challenge in electroforming processes. In this study, a dual-additive strategy is proposed by combining PEG of various molecular weights (200, 2000, and 20,000) with sodium naphthalene-1,3,6-trisulfonate (NTS) to regulate both crystal orientation and internal stress in nickel coatings. Experimental results show that high-molecular-weight PEG-20,000 promotes (111) and (220) preferred orientations while suppressing the (200) plane, thereby improving coating hardness. Molecular dynamics simulations confirm that the polymerization degree of PEG correlates positively with its adsorption energy on Ni (111), which hinders vertical grain growth and promotes lateral expansion. However, PEG also significantly increases tensile stress by inhibiting the migration of nickel atoms and expanding interplanar spacing, as evidenced by both simulation and stress measurement. The introduction of NTS effectively compensates for this effect, reducing tensile stress and enabling the attainment of zero internal stress within the concentration range of 0-1 g/L. Furthermore, COMSOL simulations were conducted to optimize the circumferential current density distribution during the electroforming of Wolter-I type Xray focusing mirrors. The results show that uniform anode configuration improves current uniformity, reduces stress fluctuations, and helps prevent mirror deformation. This work provides an effective approach for the simultaneous regulation of texture and stress in nickel electroplating and offers practical guidance for fabricating high-performance, low-stress nickel coatings in high-precision manufacturing, such as X-ray optics.

Manganese(II) oxide (MnO) is a promising cathode for aqueous zinc-ion batteries (AZIBs) but suffers from poor conductivity, sluggish kinetics, and an unclear energy storage mechanism. Herein, we report a yolk-shell structured N-doped carbon-coated MnO nanoplate (MnO@C-YS) synthesized via co-precipitation combined with polydopamine coating and pyrolysis. The optimized yolk-shell architecture features a MnO-rich core (400–500 nm) encapsulated within a conformal N-doped carbon shell with an interstitial void of 50–100 nm. This unique nanostructure synergistically buffers volume changes, facilitates ion transport, enhances electronic conductivity, and suppresses Mn dissolution. The resulting MnO@C-YS cathode delivers a high discharge capacity of 270 mAh g−1 at 0.1 A g−1, enhanced rate capability (113 mAh g−1 at 5 A g−1), and long-term cycling stability (97% retention after 1000 cycles at 1 A g−1; 73% after 4000 cycles at 5 A g−1). Ex situ characterizations reveal an activation mechanism wherein rock-salt MnO undergoes gradual in situ transformation into layered Mn7O13·5H2O, which serves as the true host for reversible Zn2+/H+ co-intercalation. The work enriches the fundamental comprehension of AZIBs and sheds light on modifing MnO electrodes for performance enhancement.

Highly thermally conductive graphene fibers (GFs) hold exceptional promise for next-generation high-flux thermal management systems, yet their integration into advanced composites remains fundamentally limited by insufficient interfacial compatibility with polymer resin. This limitation severely restricts both thermal and mechanical transfer efficiency and compromises stability under extreme thermal cycling. Herein, a molecularly tailored conjugation interfaces engineering through strategically selected silane-based molecular tethers grafted onto the wrinkled GF surfaces to establish covalent bridges into the epoxy network, effectively addressing the interfacial bonding dilemma between GFs and polymer resin is introduced. The resultant GF composites achieve a synergistic enhancement in interfacial shear strength increased by 61.6% (from 55.2 to 89.2 MPa) and a record-level in-plane thermal conductivity of 571.1 W m-1 K-1. Critically, the thermal conductivity retention consistently exceeds 98% throughout 100 thermal shock cycles (25 to 125 degrees C), confirming exceptional interfacial stability and thermal fatigue resistance. Furthermore, molecular dynamics (MD) simulations reveal that rigid benzene ring of molecular tethers interphase enables exceptional interfacial thermal conductance of 373.56 MW m-2 K-1 between graphene and epoxy, while flexible or mismatched molecular tethers agents induce disorder and weaken spectral coupling. This molecular conjugation interface engineering unlocks the interfacial design and chemistry for improving thermomechanical performances of GF composites, paving the way for robust and high-flux thermal management.

The yolk-shell structure offers the advantages of low density, high specific surface area, and tunable properties, making it an ideal microstructure for microwave absorption materials. In this study, dopamine hydrochloride served as both a carbon source and a reducing agent, converting Fe3O4 into Fe while promoting core-shell separation via volume contraction and gas release during reduction, thereby fabricating yolk-shell Fe@SiO2@C. The carbon layer improves dielectric properties, the Fe core provides magnetic loss, and the SiO2 coating enhances the magneto crystalline anisotropy and coercivity of the material. The sample exhibits excellent microwave absorption performance: a minimum reflection loss of -24.84 dB at 18 GHz with a thickness of 1.9 mm, and a maximum effective absorption bandwidth of 6.26 GHz at a thickness of 2.3 mm. This work proposes a novel preparation method for the yolk-shell structure, providing a new solution for improving the effective bandwidth of wave-absorbing materials in the future.

The electrochemical stability of redox-active polymers based on Ni(II)-Salen complexes is of critical importance for their application as electrode materials for supercapacitors and lithium-ion batteries. This study presents a systematic analysis of the influence of fluoride, chloride, and bromide anions on the redox behavior of two polymeric films: poly[Ni(Salen)] and sterically protected poly[Ni(Saltmen)]. Using cyclic voltammetry (CV), electrochemical quartz crystal microbalance (EQCM), and X-ray photoelectron spectroscopy (XPS), we identify two distinct degradation mechanisms: (1) axial coordination of halide ions to the Ni(II) center followed by demetallation, which disrupts the conjugated system and reduces conductivity, and (2) oxidative halogenation of the ligand. In the presence of chloride ions, both poly[Ni(Salen)] and poly[Ni(Saltmen)] lose approximately 70% of their initial capacity over 50 cycles, indicating progressive electrochemical degradation. In contrast, both polymers demonstrate high electrochemical stability in bromide-containing electrolytes, retaining most of their capacity under identical conditions. Fluoride coordinates without compromising redox performance, serving as a model for electrochemically inert ligands. The results highlight the critical role of both electrolyte composition and ligand design in ensuring the long-term stability of nickel-Salen polymers in energy storage devices.

Quasi-solid-state polymer electrolytes (QSPEs) hold immense promise for intrinsically safe lithium metal batteries. However, operating QSPEs in sub-zero environments exposes a critical material design conflict: achieving rapid low-temperature bulk ion transport typically necessitates highly polar solvents (e.g., DMSO), which conversely trigger parasitic reactions and dendrite growth at the lithium anode. Herein, we propose a hierarchical heterogeneous QSPE via a polymerization-induced phase separation (PIPS) strategy. The resulting biphasic structure integrates a highly conductive DMSO-LiTFSI/LiBF4 liquid microdomain within a crosslinked fluorinated polymer framework, employing a synergistic "dual-confinement" mechanism. Spatially, geometric confinement within the polymer scaffold disrupts the long-range ordering of DMSO, thereby suppressing crystallization and lowering the glass transition temperature of the phase-separated QSPEs to -100.6 degrees C and -53.8 degrees C. Interfacially, the dual-salt formulation induces an organic-inorganic bilayer SEI, completely shielding reactive DMSO from the lithium surface. Consequently, the assembled LiFePO4||Li full cells demonstrate outstanding rate capability and long-term cycling stability under rigorous sub-zero conditions, offering a highly viable structural design paradigm for extreme-environmental energy storage.

The demand for materials combining high strength with exceptional thermal conductivity is growing across aerospace, automotive, thermal management and energy applications. Graphene offers an ideal building block, but multiscale defects such as disordered stacking and voids prevent macroscopic assemblies from realizing its intrinsic properties. Here we show that ultrahigh-ratio draw spinning, enabled by the polymer-like viscoelasticity of two-dimensional sheets in viscous solvents, produces graphene fibres with a tensile strength of 5.9 GPa, a Young modulus of 963 GPa, a thermal conductivity of up to 1,720 W m-1 K-1 and an electrical conductivity of 1.3 MS m-1. A high-ratio draw spinning up to 11, combined with high-temperature annealing, efficiently removes defects and produces densely packed, highly ordered graphene fibres. These properties surpass most existing strong and thermally conductive fibres. This work provides a versatile route for assembling two-dimensional materials into high-performance macroscopic structures and expands opportunities for multifunctional materials.

We regret that this statement “This work was supported by China’s Space Origins Exploration Program.” was omitted in the beginning of the Acknowledgements.

High-performance fibers with the merits of lightweight and high strength are indispensable to modern industry. However, the performance trade-off between tensile strength and bending rigidity limits their more applicational possibilities as structural materials. Inspired by the hierarchical assembly of biomaterials, we exploit graphene fibers through multiscale fusion spinning of gel fiber bundles with an unprecedented synergy of high tensile strength of 3.0 gigapascal and bending rigidity reaching 1.6 × 106 newtons per square micrometer for a 100-micrometer-thick fiber (more than 104 times higher than Kevlar fibers). Continuous fusion-induced defect suppression produces thick fibers with homogeneous ordering and performance. These fibers also exhibit exceptional thermal and electrical conductivities, showing their potential as structure-function integrated materials. The fibers are used as wing veins, feet, or claws of robots, resisting extreme conditions including wind speed from 0 to 7 Beaufort scale, pH from 0 to 14, and temperature from 4 to 2000 kelvin. These results promise structural materials design, bionic functions, and robotics in harsh environments.

Cracking in Ni-rich layered cathode materials represents a major degradation mechanism that rapidly diminishes electrochemical performance. However, the exact origins of cracking in these materials, particularly in polycrystalline form, remain controversial due to coupled mechanical-electrochemical effects. Here, through combined thermal and electrochemical investigations, we reveal that polycrystalline LiNi0.9Co0.05Mn0.05O2 (NCM90) cathodes exhibit intrinsic mechanical toughness, tolerating thermal cycling strains up to 7% (v/v) without significant cracking, especially when composed of small primary particles, even without external modification. Further studies demonstrate that NCM90 also maintains a crack-free morphology in EC/DMC electrolyte at 55 degrees C in the absence of LiPF6. However, introducing LiPF6 induces severe particle fracture due to associated formation of HF, particularly in cathodes with larger primary particles, consistent with electrochemical degradation trends. Our findings identify HF-induced attack on polycrystalline NCM90 as the primary driver of cracking, particularly for cycling at elevated temperatures. Consequently, HF-resistant oxide doping emerges as the most effective strategy for enhancing structural stability while improving electrochemical performance, offering a practical and efficient solution for stabilizing Ni-rich cathodes.

The practical application of S-MnO2 as a cathode material for aqueous zinc-ion batteries (ZIBs) faces challenges such as structural collapse during cycling, limited ion diffusion, and poor conductivity. This study presents a novel proline (Pro)-intercalated S-MnO2 layered cathode material (S-PMO), synthesized via co-precipitation and ion-exchange methods. The rigid cyclic structure of Pro acts as "molecular pillar", while its amino and carboxyl groups enhance interlayer stability through hydrogen bonding and provide additional active sites, thereby improving cyclic stability and diffusion kinetics. Experimental results demonstrate that Pro intercalation expands the interlayer spacing and this increases the specific surface area, thereby providing more active sites and facilitating ion transport pathways for Zn2+/H+. The S-PMO cathode delivers a reversible capacity of 329 mAh g- 1 at 0.2 A g- 1 and 133 mAh g- 1 at 2.5 A g- 1. It also demonstrates excellent cycling stability, retaining 95 % of its capacity after 1000 cycles at 1.0 A g- 1, which is attributed to the highly reversible co-(de)intercalation of Zn2+ and H+. Furthermore, a flexible battery prototype demonstrates its promise for real-world utilization. This work demonstrates a viable strategy for advancing high-performance and sustainable cathode materials in ZIBs.