Black phosphorus (BP) has emerged as a highly promising material for next-generation electronics and optoelectronics because of its exceptional properties. However, the large-scale synthesis of high-quality BP films on various functional substrates remains a great challenge. Here, we report a universal van der Waals (vdW) layer passivation strategy that enables the synthesis of wafer-scale high-quality BP films on arbitrary substrates (Si, SiO 2 , SiC, GaN, sapphire, quartz, etc.). The atomic-thick passivation layer effectively eliminates the dangling bonds of the substrates and thus mitigates the effects of the substrates on BP growth by forming a vdW layer for BP nucleation and growth, thereby enabling substrate-independent synthesis of high-quality BP films via vdW epitaxy. The resulting BP films exhibit inch-scale uniformity, a high carrier mobility of ~1100 cm² V⁻¹ s⁻¹ at room temperature, and excellent electronic performance across diverse substrates. Our work provides a versatile platform for integrating high-mobility 2D materials with conventional semiconductor technologies, thus opening new frontiers for heterostructure-based devices.

Titanium dioxide (TiO2) is a promising photocatalyst for hydrogen evolution but suffers from rapid charge recombination and a lack of active sites. Although single-atom catalysts (SACs) maximize metal atom utilization, their performance is often limited by insufficient anchoring sites on the support. Here, we report a "chemical scissors" strategy to achieve enhanced synergy between palladium (Pd) single atoms and oxygen vacancies (Ov) in TiO2 through precise control of defect-mediated anchoring. By selectively etching metallic Pd particles while preserving Pd atoms anchored at oxygen vacancy sites, we successfully constructed a series of Pd1/TO-Ov catalysts with progressively increased single-atom loadings. Systematic experimental characterizations and density functional theory (DFT) calculations reveal that oxygen vacancies not only serve as preferential anchoring sites (ASs) for stabilizing Pd single atoms, but also enable strong electronic interactions that enhance the intrinsic activity of each isolated metal center. This defect-engineered synergy optimizes charge separation and maximizes active site utilization. The optimized Pd1/TO-Ov-6 catalyst exhibits a remarkable hydrogen evolution rate of 5656.67 & micro;mol g-1 h-1 and a high turnover frequency of 167.2 h-1. This work provides a rational design strategy for high performance SACs.

In-situ plasma processing serves as a cost-effective strategy for modulating surface structure while simultaneously functionalizing material surface, owing to the low-contamination environment and its capability to induce strong surface-substrate interaction. However, current research primarily focuses on correlating plasma discharge parameters with the resultant surface morphology and facet orientation, often overlooking the dynamic evolution of critical parameters during plasma processing, particularly the surface thermal field. This leads to suboptimal surface structure modulation, thereby limiting the practical applicability of plasma-based surface engineering. Herein, we introduce a facile cooling-mediated N2 plasma processing strategy to directly engineer iron nitride nano-framework on Fe surface, while concurrently modulating the surface facets. Operando plasma diagnostics, combined with numerical simulations, are employed to unravel the role of the surface-thermal field in governing the formation of catalytically favorable facets. Given the strong dependence of hydrogen evolution reaction (HER) behavior on surface structure, the resultant iron nitride frameworks via cooling-mediated plasma processing (cFeNC) exhibit improved catalytic performance compared to those fabricated through conventional thermally preserved plasma (hFeN). Density functional theory (DFT) calculations further confirm that the enhanced catalytic behaviors of cFeNC arise from the preferential exposure of highly reactive facets. Our strategy presents a cost-effective pathway for facet engineering of nitride surfaces, providing a promising route towards advanced electrocatalytic materials. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Photocatalytic CO2 reduction reaction (PCRR) offers a sustainable route for solar-to-chemical energy conversion, yet the mass transport processes involved, which strongly affect its efficiency, remain poorly quantified experimentally. Here, we develop a mass transport model suitable for the actual reaction conditions of particulate photocatalysts in a continuous stirred tank reactor (CSTR). By integrating macroscopic flow convection, mesoscopic diffusion, and microscopic interfacial adsorption, the model quantitatively reveals the transport dynamics of involved species, the evolution of the reaction microenvironment, and the hydrophobic effect of the catalyst surface. Consequently, a substantial increase in OH- concentration and a noticeable decrease in CO2 concentration near the catalyst surface are observed. For a cuprous oxide photocatalyst with a water contact angle of 130 degrees, the interfacial CO2 concentration increases by more than 20-fold compared to that in the adjacent solution, supporting the improved experimental PCRR performance following surface hydrophobic modification. Our model offers constructive guidance for the development of more efficient CSTR-based PCRR systems.

Distinct material phase modulation is widely regarded as a key strategy for tailoring the surface properties of nano-frameworks. Plasma has emerged as an effective method for in situ phase modulation directly on substrate surfaces. However, the persistent vertical bombardment of reactive species in a conventional plasma system inevitably leads to excessive surface etching, thereby compromising the distinction and quality of surface structural engineering. Herein, we introduce a novel magnetically confined plasma strategy that enables the unique phase modulation of iron nitride nano-frameworks on iron substrates. By varying the magnetic field strength, the resultant iron nitride phase transitions from orthorhombic Fe2N to trigonal Fe2N, with a well-defined exposed facet, is achieved. In contrast, the conventional plasma nitridation predominantly yields hexagonal FeN. Operando plasma diagnostics and numerical simulations are employed to elucidate the underlying mechanism governing phase modulation. The superior distinction of phase modulation via magnetically confined plasma processing is further validated by comparing with conventional plasma nitridation under varying discharge parameters. Such apparent structural differences of nitrides via magnetically-confined plasma are confirmed through the corresponding electrocatalytic performance evaluation and theoretical calculations. Such an approach offers a promising pathway for the distinct structural engineering of nitrides directly on the substrate surface toward improved electrocatalytic behavior.

Methane dry reforming offers a promising approach for converting CH4 and CO2 into valuable syngas, while its application is restricted by catalyst deactivation and carbon deposition. Here, we report a well-designed heterostructured plasmonic photocatalyst consisting of a plasmonically active Ag core and a catalytically active Ir cage selectively grown on the vertices and edges of the Ag core, which preserves strong plasmonic absorption and enables the significant concentration of electromagnetic energy on the Ir cage, as well as the selective dissipation of that energy to generate hot carriers. This heterostructured plasmonic photocatalyst demonstrates long-term stability (300 h), high selectivity (>97%), and much enhanced H2 and CO production in light-driven methane dry reforming. We demonstrate that light-excited hot carriers, coupled with electron-enriched Ir sites, enhance the activation of CO2 and CH4, and facilitate the conversion of *CH intermediates to *CHO, thereby preventing coke formation and contributing to the high catalytic performance.

Photocatalytic hydrogen evolution from water is considered a promising route for solar energy utilization. However, the efficiency of plasmonic photocatalysts under broad-spectrum sunlight remains hampered by inefficient charge management. Systems such as TiO2/Au suffer from electron counterflow under simultaneous UV and visible excitation: UV-excited electrons in TiO2 migrate toward Au, while visible-light-induced hot electrons from Au inject into TiO2, resulting in severe recombination losses. Here, we construct a ternary TiO2/Au-Pt heterostructure with a deliberately aligned Fermi-level gradient (TiO2 → Au → Pt), establishing a unidirectional, downhill electron-transfer pathway. This stepwise energy alignment channels both UV- and visible-light-excited electrons sequentially to Pt catalytic sites, effectively suppressing charge counterflow and maximizing electron utilization. Consequently, TiO2/Au-Pt achieves a remarkable H2 evolution rate of 16.67 mmol g-1 h-1 under broad-spectrum irradiation, surpassing those of TiO2/Au and TiO2/Pt by factors of 3.18 and 2.32, respectively, while maintaining excellent stability over 20 h. This Fermi-level-guided strategy provides a general paradigm for engineering multicomponent photocatalysts with optimized interfacial energetics toward efficient broad-spectrum solar-to-hydrogen conversion.

Metastable wurtzite transition-metal compounds are of interest because their hexagonal symmetry can enable electronic and magnetic behaviors inaccessible to thermodynamically stable phases. Their synthesis in the 2D limit, however, remains challenging. Here, we demonstrate the direct growth of metastable 2D wurtzite MnS nanosheets by atmospheric-pressure chemical vapor deposition via sulfur-vacancy engineering. Ultrathin MnS nanosheets with lateral dimensions of tens of micrometers are grown in a 10 min deposition step. Phase selection is controlled by the cooling atmosphere: interrupting the gas flow after growth creates sulfur-deficient conditions, promotes sulfur-vacancy formation, and stabilizes the wurtzite phase, whereas continuous flow supply yields the stable rock-salt phase. Transmission electron microscopy and grazing-incidence wide-angle X-ray scattering confirm the wurtzite structure, and electron paramagnetic resonance spectroscopy reveals abundant sulfur vacancies. The nanosheets exhibit p-type semiconducting transport, negative magnetoresistance up to room temperature, and a low-temperature exchange-bias effect. These results identify sulfur vacancies as a key determinant of metastable phase stabilization and provide a design principle that may be extendable to other chalcogenide systems.

Achieving strong magnetoelectric coupling (MEC) together with large ferroelectric polarization remains a central challenge in type-II multiferroics. In conventional spin-driven multiferroics, the induced polarization is usually mediated by spin-orbit coupling (SOC) or spin-lattice coupling (SLC). Since many representative systems are based on 3d transition-metal ions, where SOC is relatively weak and SLC-induced lattice distortions are often limited, their polarizations are typically much smaller than those of proper ferroelectrics. Moreover, electric polarizations in type-II multiferroics are generally induced by spiral spin orders stabilized by competing magnetic interactions, which often leads to relatively low magnetic transition temperatures. In this Letter, using spin-group symmetry, we propose an SOC- and SLC-independent route to MEC in collinear 3d magnetic systems. We show that, even for a noncentrosymmetric lattice structure, different collinear magnetic configurations can either forbid or allow electric polarization, indicating direct magnetic control of polarization and hence strong MEC. The first-principles calculations excluding SOC on monolayer 2H-VS2 support this picture: a collinear stripy antiferromagnetic order induces an in-plane ferroelectric polarization up to 25.00 μC/cm2, about two orders of magnitude larger than that of typical type-II multiferroics. Furthermore, our microscopic model suggests that the induced polarization originates from SOC-independent p-d hybridization governed by electronic hopping. Our results suggest a possible route toward type-II multiferroics combining strong MEC with large electronic polarization in collinear 3d magnetic systems.

Out-of-plane polarization in two-dimensional sliding ferroelectrics mainly arises from interfacial charge redistribution and interlayer charge transfer induced by interlayer sliding. However, intrinsic systems generally exhibit weak polarization and face intrinsic challenges in incorporating magnetism. In this work, BN/BN homostructures and Gr/BN heterostructures are used as representative models to investigate how B, N, and C vacancy defects modulate charge transfer, out-of-plane polarization, and magnetism in bilayer and trilayer stacked structures. The results show that vacancy defects break the symmetry of the interfacial charge distribution and enhance interlayer charge transfer, thereby substantially amplifying the out-of-plane polar response. In trilayer structures, a defective middle layer induces a cumulative two-step charge-transfer mechanism, enabling BN/VN@BN/BN to exhibit two oppositely polarized states of approximately +5.5 and − 5.5 pC/m. This polarization enhancement exceeds that of the intrinsic trilayer structure and cannot be described as a simple superposition of the corresponding bilayer contributions. Minimum-energy-path calculations reveal that BN/VN@BN/BN and Gr/VN@BN/Gr can undergo continuous polarization reversal through cooperative interlayer sliding, with energy barriers of approximately 9 and 14.5 meV/u.c., respectively. Meanwhile, both classes of systems exhibit the coexistence of polarity and magnetism characteristic of type-I multiferroics. The former is half-metallic, whereas the latter is metallic; however, the magnetoelectric coupling remains weak. A high-concentration vacancy model is adopted in this work, and the results primarily elucidate the fundamental mechanisms by which vacancy defects enhance sliding-induced polarization and induce polar-magnetic coexistence, thereby providing theoretical guidance for the design of experimentally accessible two-dimensional systems.

Plasma-substrate interactions have attracted considerable attention for their potential in optimizing surface structure modulation. However, most studies focus on initial discharge parameters, while the fundamental influence of plasma environment on the intrinsic properties of the substrate during processing has been largely overlooked, limiting the precision of surface structural control. Here, we report a novel phenomenon: the ferromagnetism collapse of metallic Ni during low-pressure glow discharge plasma processing. The intrinsic ferromagnetic behavior of Ni is transformed into the diamagnetic state during plasma processing and it is reversed back to ferromagnetic state once the plasma is switched off. Such transition in magnetic behavior of Ni is observed under N2, O2 and H2 plasma environments. Through the combination of operando plasma diagnostics and numerical simulations, it is demonstrated that reactive species in different plasmas are adsorbed on substrate surface under the confinement of plasma sheath. Such adsorption significantly reduces the ferromagnetic stability of Ni, leading to the ferromagnetism collapse. Such discovery provides new insights into plasma-substrate interactions and offers a comprehensive scientific basis for understanding and controlling the surface magnetic properties of Ni during plasma processing.

The relative atomic-scale motion between layers in van der Waals layered materials offers a new route to realizing two-dimensional ferroelectricity. However, directly measuring the extent of interlayer sliding remains challenging. Here, we use wide-field second-harmonic generation (SHG) imaging to quantitatively map interlayer sliding in few-layer 1T'-ReS2, a model platform enabled by centrosymmetry in each monolayer and weak coupling between layers. We discover multiple discrete stacking configurations in the trilayer and four-layer samples, manifested as characteristic SHG intensity values. Corroborated by Raman and photoluminescence (PL) spectroscopy, we demonstrate that these states arise from anisotropy-confined translational interlayer sliding along the b-axis, which also subtly modulates the electronic structure by ∼5 meV. Our results present the quantitative optical imaging of discrete interlayer sliding in 1T'-ReS2, offering direct evidence to understand and manipulate two-dimensional sliding ferroelectricity.

Phase transition in van der Waals (vdW) two-dimensional (2D) materials is an effective approach to create novel and tunable electronic states for potential applications in next-generation quantum electronics. Here, we propose an unusual non vdW phase transition behavior in 2D layered transition metal dichalcogenides (TMDs). As interlayer distance decreases below the common vdW gap upon pressure, interfacial ligand-ligand chemical bonds could form to stabilize the system and result in a phase transition to a non vdW structure, which exhibits interesting electronic and magnetic properties very different from the pristine vdW one. Based on first-principles calculations, we predict stable non vdW phase transitions in CrS2 and other TMD bilayers, characterized by the formation of interlayer S-S single covalent bonds, which is accompanied by metal-semiconductor, nonmagneticmagnetic and/or magnetic phase transitions. These findings elucidate a general phase-transition mechanism in vdW 2D materials driven by out-of-plane pressure, suggesting a viable strategy to exploring potential quantum electronic states for diverse functional applications.

Solid-state lithium metal batteries (SSLMBs) hold great promise for safe and high-energy-density storage. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)-based composite polymer electrolytes (CPEs) with garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO) fillers are attractive but suffer from the detrimental Li2CO3 layer on LLZTO, which hinders ion transport and triggers polymer decomposition. Herein, we introduce a plasma-assisted strategy to in situ convert the Li2CO3 layer into a uniform 15 nm LiF coating. This LiF interphase not only mitigates the alkalinity to suppress dehydrofluorination but also promotes the transformation of PVDF-HFP from the α-phase to the electroactive β-phase, enhancing Li salt dissociation and creating robust ion transport pathways across the PVDF-HFP/LLZTO interface. Consequently, the LiF coating increases the intrinsic ionic conductivity contribution of the LLZTO filler by 12.6%–17.5% (semi-quantitative results from 6Li solid-state nuclear magnetic resonance analysis). The optimized CPE exhibits a high ionic conductivity of 6.65×10−4 S cm−1 and enables stable lithium plating/stripping for 3000 h. The corresponding SSLMB delivers excellent cyclability with 88.5% capacity retention after 140 cycles at 2 C, highlighting the efficacy of this interfacial engineering approach.

Magnetic structures, which play a central role in determining their physical properties, are known for only very limited compounds. Traditional theoretical approaches to predicting magnetic structures predominantly rely on first-principles calculations. A key challenge of these methods is their requirement for initial magnetic configurations as inputs, which theoretically possess infinite possibilities. In this work, we introduce a strategy based on irreducible representation basis vectors that effectively narrows down the vast space of potential magnetic configurations to a finite set, typically comprising around 20 candidates per material. Despite this significant reduction, the compact input sets generated by our method already encompass the experimental magnetic structures for 253 out of 302 benchmark materials (83.8

The electrochemical reduction of nitric oxide (NORR) represents a promising route for both mitigating nitrogen oxide pollution and enabling sustainable ammonia synthesis. Iron-polyphthalocyanine (FePPc), characterized by its well-defined Fe-N4 structure, has shown remarkable catalytic activity; however, its spin-involved reaction mechanism and its impact on selectivity remain unclear. Moreover, the influence of spin-dependent effects on the reaction pathways in graphene-based single-atom catalysts has received scant attention, limiting the fundamental understanding of spin-activity relationships in electrocatalysis. In this work, we employ constant-potential density functional theory (DFT) calculations to investigate the NORR mechanism on FePPc, focusing on the competition between NH3 and NH2OH formation. Our results reveal that the spin state of key intermediates is potential-dependent, with spin crossover occurring at critical reaction steps. This potential-driven spin-crossing phenomenon directly dictates the reaction trajectory, leading to a shift in product selectivity between NH3 and NH2OH under varying applied potentials. We demonstrate that the spin-crossover mechanism is essential for understanding and controlling product distribution under operational electrochemical conditions. These findings provide new insights into the role of spin states in tuning the selectivity of single-atom catalysts for nitrogen oxide reduction and highlight spin engineering as a critical design principle for advanced electrocatalysts.

Light-element magnets with superior mechanical hardness are crucial for ensuring spintronic reliability under external mechanical strain; however, the dense covalent cross-linking required to sustain structural robustness typically forces exhaustive valence electron pairing, universally quenching the localized magnetic moments essential for long-range collective ordering. In this work, we demonstrate that this antagonistic hardness-magnetism trade-off can be circumvented through a hierarchical interstitial welding strategy. Through first-principles calculations, we predict that a novel carbon allotrope, D6hAA, hosts robust intrinsic antiferromagnetism (AFM) accompanied by exceptional lattice rigidity. This phase is generated by inserting guest carbon atoms into a D2hAA precursor—a 3D C36 fullerene framework wherein the cages are laterally fused via in-plane [2+2] cycloadditions and vertically coupled through AA-stacked C–C bonds. This interstitial welding triggers a spatial redistribution of localized magnetic centers: while the intrinsic cage electrons of the precursor pair to construct the rigid 3D scaffold, the inserted guest atoms remain three-fold undercoordinated. These interstitial sites act as new localized magnetic centers (∼0.37μB), which are strictly dominated by unpaired out-of-plane pz orbitals. Furthermore, the exceptional rigidity of the carbon skeleton (ΘD=1727 K) effectively suppresses low-frequency lattice vibrations, minimizing spin-phonon decoherence channels. Finally, an interlayer sliding mechanism is shown to drive a magneto-electronic phase transition within the unwelded template, where a mechanical shift from AA to AB stacking disrupts interlayer orbital alignment of pz orbitals, expanding the hybrid functional HSE06 bandgap from 1.06 eV to 2.06 eV. Our findings establish a compelling structural paradigm for securing intrinsic long-range order within robust, fatigue-resistant metal-free networks.

The design of the catalytic center that facilitates electron accumulation and CO2 activation is central to enhancing the efficiency and selectivity of photocatalytic CO2 reduction reactions. Here, a novel quantum tunneling-assisted catalytic center is constructed based on an architecture comprising an ultrathin MgO film coated on Pt nanoparticles supported on a TiO2 substrate. This design not only increases electron concentration at the surface active sites but also optimizes surface properties to promote CO2 activation. As a result, the catalyst achieves a CH4 selectivity of up to 93.6%, representing a significant advancement in CO2-to-fuel conversion. Mechanistic investigations from in situ Fourier-transform infrared spectroscopy and density functional theory calculations reveal that the MgO surface, which effectively adsorbs CO2 molecules, exhibits tunable selectivity toward *CHO formation and CO desorption under varying electron concentrations. This work provides new insight for the development of advanced catalytic centers for CO2 conversion.