Low-dose high-resolution integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM) directly visualizes the breathing behavior of flexible MIL-88B. Solvent-induced breathing involves anisotropic lattice deformation, cooperative linker tilting, and cluster reorientation, while localized screw dislocations reveal defect-assisted strain accommodation during large-amplitude framework expansion.

Abstract Efficient bulk photovoltaic (BPV) conversion and room-temperature ferromagnetism are difficult to combine, because the itinerant electrons that support magnetic order favor metallic transport, whereas BPV generation requires a semiconducting state with broken inversion symmetry. Here, we show that oxygen-plasma implantation transforms metallic Fe 3 GaTe 2 into a ferromagnetic semiconductor with a giant BPV response, enabling zero-bias photocurrent generation in a non-centrosymmetric lattice. Oxygen incorporation localizes itinerant Fe d -electrons, induces p-type semiconducting transport and polar electronic structure, while oxygen-associated exchange pathways allow persistent ferromagnetic state above room temperature. The resulting devices exhibit spontaneous broadband photoresponse, with short-circuit current densities approaching 30 A cm −2 and a BPV coefficient up to 0.25 V −1 . The photovoltaic current can be linearly programmed by low magnetic fields based on field-dependent magnetoresistive modulation. Using the experimentally calibrated device response, we demonstrate magnetically programmable feature separation and image restoration with 92.3% recognition accuracy, establishing oxygen-engineered Fe 3 GaTe 2 as a platform for self-powered, reconfigurable magnetic optoelectronics.

The commercial oxygen reduction reaction (ORR) catalysts applied in zinc-air batteries and hydrogen fuel cell are seriously restricted due to the rapid decline in activity, rare precious metals and high price. Hence, exploring non-noble metal catalysts with high efficiency, stability as well as low cost is crucial for large-scale production of catalysts. In this study, N-doping carbon-coated FeCo alloy core-shell nanoparticles were synthesized through DC arc plasma method. Experiment results showed excellent ORR electrocatalytic activity and stability. The initial potential and half-wave potential of FeCo@C(N10) were 0.88 V as well as 0.79 V, which were close to commercial Pt/C. Moreover, the limited current density was 6.29 mA cm-2, which was higher than that of commercial Pt/C and superior to the catalysts without N and N2 doping. The negative shift of half-wave potential of FeCo@C(N10) was only 7 mV after 5000 CV cycles while commercial Pt/C catalyst decreased by 16 mV. This study provided an innovative method for large-scale production of electrocatalysts which demonstrated both excellent ORR electrocatalytic activity and stability.

The core-shell nanocapsules of base metal Ni coated with CaZrO3 ceramics for the inner electrodes of MLCCs are synthesized in situ by Direct Current (DC) arc plasma evaporation method in nitrogen-rich atmosphere. Its size structure, elemental valence (Ca, Zr, O, Ni) and composition are characterized, which can then regulate the application performance of the powder. According to the oxygen vacancy mechanism and oxygen potential principle, the aerosol growth model is introduced to explain the mechanism of synthesizing Ni@CaZrO3 nano-capsules. It is confirmed that there is a doping threshold (2:8) during the co-evaporation of CaZrO3 and Ni. The experiment results show that the prepared nanoparticles are pure in phase, with the average grain sizes reaching nanometer scale and displaying the smooth "core-shell" spherical structure. Among them, when the doping amount of CaZrO3 is x = 20 wt% (Ni80@CZO20), the shell thickness of CaZrO3 is about 4 nm, the average grain size is 27 nm, and the oxidation resistance temperature is 429.5 degrees C (29.7 degrees C higher than that of pure nickel samples). The trace amount of Ca(OH)2/CaCO3 formed due to Ca element intake contributes to enhancing its short-term stability during storage at ambient temperature. The sintering shrinkage rate is reduced to 6.68%, and the difference with the BaTiO3 dielectric layer (5.88%) is narrowed to 0.8%. Meanwhile, the violent shrinkage temperature is delayed to 685 degrees C (pure Ni is 647 degrees C), which improves sintering performance. Additionally, the Ni@CaZrO3 core-shell structure shows the high Q value (855.3) and low AC electrical conductivity (sigma ac = 61.19 & times; 105 S/cm) while maintaining high electrical conductivity (266.1 S/cm), indicating that it has low dielectric loss characteristics. Based on this, Ni@CaZrO3 can provide potential substrates for high-level MLCCs through the core-shell synergistic effect, and the kilogram mass production capacity of DC arc method lays down the technical support for industrial production.

Developing efficient non-precious oxygen reduction reaction (ORR) catalysts is essential for advancing zinc-air batteries (ZABs). This work presents a one-step synthesis of core-shell Cr3C2@C nanoparticles (NPs) via DC arc-discharge plasma. Precise regulation of cooling dynamics achieves a switch from growth-dominated to nucleation-dominated regimes, enabling controlled preparation of nanoparticles with distinct sizes. The liquid-nitrogen-cooled Cr3C2@Cln NPs exhibit smaller size and higher surface area, leading to enhanced ORR performance. Subsequent nitrogen doping at 700 °C produces Cr3C2@Cln(Nx) catalysts with precisely tuned nitrogen content (0.65-1.24 at.%). The optimized Cr3C2@Cln(N1.13) demonstrates outstanding ORR activity with a half-wave potential (E1/2) of 0.81 V and superior kinetics, surpassing commercial Pt/C. In situ optical emission spectroscopy (OES) monitors the plasma state and electron temperature, providing fundamental insights into nucleation mechanisms. Density functional theory (DFT) calculations reveal that nitrogen doping optimizes the p-band center of carbon and significantly reduces the energy barrier of the rate-determining step (RDS) (*OH desorption). When applied in both liquid and solid-state flexible zinc-air batteries (FZABs), the Cr3C2@Cln(N1.13)-based cathode delivers exceptional performance, achieving high power densities (230.64 and 164.83 mW·cm-2, respectively) and remarkable cycling stability. This study offers an efficient strategy for designing high-performance transition metal carbide electrocatalysts through synergistic control of size and electronic structure.

In-situ synthesis of "metal-ceramic" core-shell Ni@CaTiO3 nanocapsules for MLCC inner electrodes by DC arc plasma evaporation method in nitrogen-rich atmosphere. By adjusting the doping amount of CaTiO3 (CTO), it is proved that the composition of co-evaporation process is controllable, and the optimal doping ratio is x = 30 wt% (Ni-70@CTO30, 3:7). The experimental results show that the nanoparticles are pure in phase, and present the clear core-shell sphere. Among these, when the doping amount of CTO is x = 30 wt%, the thickness of CTO shell is about 5.9 nm, the average particle size is 20 nm, the oxidation resistance temperature is 428.3 degrees C, and the oxidation rate is only 37.79%. Moreover, compared with the thermal shrinkage of pure nickel powder for production (12.77%) and S1 sample (15.31%), the E4 (3:7) sample is only 4.99% at the sintering temperature of 1200 degrees C, and the severe shrinkage temperature range is delayed to similar to 700 degrees C. Meanwhile, the thermal shrinkage of E4 sample mixed with BaTiO3 (BTO) powder is only 5.44%, and the matching difference with BTO is only 0.44%. Furthermore, while maintaining high conductivity (294.2 S/cm), the Q value of E4 sample is 407.68, which rises to 474.75 after being doped with BTO. Based on this, through the core-shell synergistic effect, Ni@CaTiO3 nanocapsules provide potential basic materials for the next generation of miniaturized and highfrequency base metal MLCC and its industrial production.

Developing efficient non-precious oxygen reduction reaction (ORR) catalysts remains a critical challenge. Herein, a direct current (DC) arc plasma strategy was demonstrated to construct nitrogen-doped carbon-coated Ni-ZrC heterostructured nanoparticles ((Ni/ZrC)@NC NPs) with precisely tuned interfacial built-in electric fields (BIEFs). Theoretical studies reveal that the significant work function difference (ΔΦ) drives an asymmetric charge redistribution at the Ni-ZrC heterointerface, shifting d-band centers to optimize the adsorption energy of oxygen intermediates and to reduce reaction energy barriers. In situ optical emission spectroscopy (OES) captures the dynamic plasma evolution (electron temperature (Te) at local thermal equilibrium (LTE): 10,330.9 K), elucidating real-time atomic/ionic flux variations and formation mechanism of the core-shell structure and heterostructure. The synergistic Ni-ZrC core and N-doped carbon shell cooperatively enhance charge transfer kinetics and expose abundant active sites. The resulting catalyst achieves exceptional ORR activity with a half-wave potential (E1/2) of 0.82 V, surpassing Pt/C (0.80 V), alongside superior methanol tolerance and 4e− selectivity. When deployed in both liquid and all-solid-state flexible zinc-air batteries (FZABs), the catalyst delivers superior metrics: peak power densities of 251.63 mW cm−2 (liquid) and 184.22 mW cm−2 (flexible), and stable operation for a long time. This work establishes a paradigm for manipulating interfacial electronic structures via BIEFs engineering, providing a versatile platform for high-performance energy conversion technologies.

Developing efficient strategies for electrically manipulating two-dimensional magnetism at room temperature is a key challenge in contemporary spintronics. In this study, we demonstrate giant electromechanical control over the magnetism of the room-temperature van der Waals ferromagnet Fe3GaTe2 by integrating it with the ferroelectric α-In2Se3. Modest gate voltages lead to an almost complete suppression of the coercive field by 96.5

To address the issues of pure Cu powder in conductive pastes, such as easy oxidation, rapid decline in electrical conductivity, and poor applicability in industrial sintering, submicron Cu-Sn alloy particles for conductive pastes are successfully prepared via the direct current arc plasma method under the nitrogen atmosphere. The submicron Cu-Sn alloy particles are systematically characterized. The initial electrical conductivity of the Cu70 sample is 298 S/cm, and after heat treatment, the electrical conductivity reached 2212.5 S/cm. The superior oxidation resistance of Cu70 originates from the combined effect of Cu-Sn intermetallic phases and a Sn-containing passivation layer, which suppresses oxygen diffusion and delays the formation of insulating copper oxides. After heat treatment, defect relaxation, improved crystallinity, interparticle neck formation and reduced contact resistance jointly contribute to the remarkable enhancement in electrical conductivity. The results show that superior oxidation resistance compared with pure Cu, and favorable electrical conductivity after high-temperature sintering. This can be expected to serve as a novel conductive powder material for the next generation of economical and environment-friendly electronic pastes.

Carbon nanotubes (CNTs), characterized by their low density, high specific surface area, and excellent electrical conductivity, hold significant promise for applications in electromagnetic protection. In this study, to effectively address the challenge of interfacial impedance mismatching, we developed a rapid and efficient arc discharge plasma method for the in situ synthesis of CNTs on a silver (Ag) matrix, resulting in Ag@CNT nanocomposites. The microstructure, morphology, and surface chemical composition of the as-prepared nanocomposites were characterized in detail. The nanocomposites exhibited dielectric loss and weak ferromagnetism, attributed to the reduced crystallinity, broken bonds, and abundant defects introduced at the CNTs and Ag-C interfaces. These features significantly enhanced impedance matching with incident electromagnetic waves. Electromagnetic wave absorption performance was evaluated for paraffin-based composites containing 30 wt% Ag@CNTs. The material achieved a minimum reflection loss (RL) of -39.8 dB at 13.8 GHz, with an effective absorption bandwidth (RL below -10 dB) spanning from 11.7 to 15.7 GHz at a matching thickness of just 1.6 mm.

Silver (Ag) can endow tantalum (Ta) with antibacterial properties, which is crucial for bone implant applications. While the osteogenic and antibacterial properties of bimetallic Ta-Ag nanoparticles (NCs) have not been studied, in this paper, Ta-Ag NCs with different Ta contents were first synthesized by the nucleation growth of gaseous atoms, an arc-discharge plasma method under a mixed atmosphere of hydrogen and argon. The as-prepared Ta-Ag NCs consist of Ta phases and Ag phases, and the grain sizes are 10-80 nm and gradually enlarged with the increase of Ta ratio. The antibacterial efficiency of Ta-Ag NCs is positively proportional to Ta content, and the bacteriostatic mechanism is attributed to the galvanic corrosion effect of the Ta-Ag interface. Furthermore, the Ta-Ag NCs possess good cytocompatibility and can reduce pro-inflammatory cytokines, increase anti-inflammatory cytokines, and promote the expression of osteogenetic genes. Meanwhile, the comprehensive performance is enhanced with an increase in Ta content. Altogether, such Ta-Ag NCs show greater potential in orthopedic applications.

Ni@CaO nanocapsules for multilayer ceramic capacitors (MLCCs) inner electrodes are synthesized in situ by the DC arc plasma method under nitrogen-rich atmosphere, and their structures, ionic valence states (Ca2+, O2-, Ni2+/3+), compositions, and other properties are characterized and tested. Based on the principle of oxygen potential, the aerosol growth model is introduced to explain the mechanism of synthesizing Ni@CaO nanoparticles, and it is confirmed that the composition ratio of CaO and Ni can be controlled during co-evaporation. The results show that the prepared pure nickel and all Ni@CaO nanoparticles are pure in physical phase, and the average grain sizes reach the nanometer scale with the smooth "core-shell" spherical structure, and the thickness of CaO shell is approximately 1.5 nm. According to the performance test results, the optimal doping ratio of Ni(100-x)@CaO(x) is determined to be 2:8 (CaO:Ni); its average grain size reaches 25 nm, and the oxidation temperature is 454.5 °C, which is 54.7 °C higher than that of the pure nickel samples. Meanwhile, the shrinkage rate of the scale sample decreased from 12.77% of the pure nickel powder for production and 15.31% of the pure nickel sample for S1 to 9.75% at a BaTiO3 matching temperature of 1200 °C. The variation law of the relationship between nanoparticle size unity and performance is verified. Moreover, its dielectric loss (tan δ) in high-frequency environments is only 0.03, which is greatly reduced, compared to the 0.05 of pure nickel, and can provide larger Q values. Based on this, the characteristics of DC arc plasma method are highlighted, such as simple material and simple process; due to the advantages of high stability and high melting point of CaO, the prepared Ni@CaO powder can be used as the potential substrate for the industrial production of the new generation of MLCCs devices.

Ni@TiO2 core-shell nanocapsules (NCs) were synthesized in-situ using a DC arc plasma in a nitrogen atmosphere. Compared to bare Ni nanoparticles, the coated Ni@TiO2 nanocapsules exhibit enhanced oxidation resistance, thermal stability, delayed initial sintering temperature, and controllable thermal expansion. The sample with 30 wt% TiO2 addition shows an onset oxidation temperature of 251.9 degrees C and a sintering shrinkage of 5.4 % at 1200 degrees C. The TiO2 shell demonstrates high compatibility with the Ni core and an excellent quality factor (Q), with the 5 wt% TiO2 addition sample achieving a maximum Q value of 16.5 at 12.3 GHz. Additionally, the DC arc method enables the in-situ preparation of Ni@TiO2 NCs under a nitrogen atmosphere, making it suitable for large-scale industrial production. Thus, Ni@TiO2 NCs present a promising material for next-generation radiofrequency multilayer ceramic capacitors (RF-MLCCs).

Electromagnetic pollution is escalating in the advent of the 5 G and forthcoming 6 G era. Ti3C2TX MXene, an emergent two-dimensional material, has been extensively applied in the field of electromagnetic absorption and shielding owing to its high electrical conductivity, adjustable interlayer spacing, and substantial surface area. However, its practical application as an absorber is severely limited by challenges including face-to-face restacking, surface modification difficulties, and poor impedance matching. Here, carbon-coated NiFe alloy nanoparticles (NiFe@C NPs), fabricated using the DC arc-discharge technique, are electrostatically self- assembled with MXene. This process effectively reduces self-stacking and enhances impedance matching properties. The robust magnetic coupling within NiFe alloy compensates for the deficiency in the magnetic loss capacity of carbon and MXene, while defects in the carbon layer and terminal groups on MXene's surface facilitate dipolar polarization. Furthermore, the heterogeneous interfaces between NiFe@C NPs and MXene produce localized dielectric polarization fields that are conducive to enhancing interfacial polarization. Additionally, the multilayered structure of MXene promotes multiple reflections and scattering of incident electromagnetic waves. When the NiFe@C/MXene composite has a thickness of 2.3 mm, it reaches a minimum reflection loss of-38.40 dB. Computer Simulation Technology (CST) results confirm the high radar cross section reduction value (17.21 dB & sdot;m2), indicating the potential of multi-component NiFe/carbon/MXene composite for microwave absorption.

Prussian blue analogs (PBAs), as a classical kind of microporous materials, have attracted substantial interests considering their well-defined framework structures, unique physicochemical properties and low cost. However, PBAs typically adopt cubic structure that features small pore size and low specific surface area, which greatly limits their practical applications in various fields ranging from gas adsorption/separation to energy conversion/storage and biomedical treatments. Here we report the facile and general synthesis of unconventional hexagonal open PBA structures. The obtained hexagonal copper hexacyanocobaltate PBA prisms (H-CuCo) demonstrate large pore size and specific surface area of 12.32 Å and 1273 m2 g−1, respectively, well exceeding those (5.48 Å and 443 m2 g−1) of traditional cubic CuCo PBA cubes (C-CuCo). Significantly, H-CuCo exhibits much superior gas uptake capacity over C-CuCo toward carbon dioxide and small hydrocarbon molecules. Mechanism studies reveal that unsaturated Cu sites with planar quadrilateral configurations in H-CuCo enhance the gas adsorption performance. The unconventional hexagonal phase CuCo PBA with open structure, large pore size, and high specific surface area is synthesized, and it delivers much better small molecular gas adsorption performance than the traditional cubic counterpart.

The shift to renewable energy has driven the development of efficient catalysts, with atomically dispersed metal catalysts (ADMCs) on porous organic materials (POMs) gaining attention for their high efficiency and stability.

Two-dimensional (2D) materials have long been considered as ideal platforms for developing separation membranes. However, it is difficult to generate uniform subnanometer pores over large areas on 2D materials. We report that the well-defined eight-membered ring (8-MR) pores, typically formed at the boundaries of two antiparallel grains of monolayer molybdenum disulfide (MoS2), can serve as molecular sieves for efficient water-ion separation. The density of grain boundaries and, consequently, the number of 8-MR pores can be tuned by regulating the grain size. Optimized MoS2 membranes outperformed the state-of-the-art membranes in forward osmosis tests by demonstrating both ultrahigh water/sodium chloride selectivity and exceptional water permeance. Creating precise pore structures on atomically thin films through grain boundary engineering presents a promising route for producing membranes suitable for various applications.

Radioactive molecular iodine (I2) is a critical volatile pollutant generated in nuclear energy applications, necessitating sensors that rapidly and selectively detect low concentrations of I2 vapor to protect human health and the environment. In this study, we design and prepare a three-component sensing material comprising reduced graphene oxide (rGO) as the substrate, silver iodide (AgI) particles as active sites, and polystyrene sulfonate as an additive. The AgI particles enable reversible adsorption and conversion of I2 molecules into polyiodides, inducing substantial charge density variation in rGO. This mechanism facilitates exceptional sensitivity and selectivity, ultrafast response and recovery times, and room-temperature operation. A multifunctional sensor prototype fabricated utilizing this material achieves the fastest reported response/recovery times (22/22 seconds in dynamic mode and 4.2/11 seconds in static mode) and a detection limit of 25 ppb, surpassing standards set by the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH), while outperforming commercial I2 gas sensors. This work provides profound insights into the design of I2 sensing materials and mechanisms for real-world applications. This study presents an iodine sensor fabricated using AgI-functionalized graphene, which exhibits fast response and recovery times with an ultralow detection limit, surpassing safety standards and outperforming commercial counterparts

In order to solve the problem of mismatch in shrinkage between the BaTiO3 dielectric layer and Ni inner electrode layer during the sintering process of multilayer ceramic capacitors, the core-shell Ni@BaTiO3 nanocapsules are synthesized in-situ by DC arc plasma method. During the co-evaporation process in the thermal plasma, O atoms preferentially combine with Ba and Ti according to the oxygen potential rule, subsequently forming Ni@BaTiO3 nanocapsules. The phase composition and microstructure of Ni@BaTiO3 nanocapsules was confirmed by characterization techniques including XRD, TEM, and XPS. The dense BaTiO3 coating on the Ni particle surface enhances both the antioxidant properties and the sintering shrinkage rate of the nanocapsules. Among them, samples with 10 wt% addition of BaTiO3 exhibited less voids and higher continuity after sintering, with an increase in oxidation temperature of about 26 degrees C and a sintering shrinkage rate of 6.71 %, while the electrical properties of the coated sample are comparable to those of the pure Ni sample. The Ni@BaTiO3 nanocapsules demonstrate excellent sintering shrinkage characteristics and oxidation resistance, and are expected to be novel electrode materials for multilayer ceramic capacitors.

Achieving scalable commercialization of zinc-air batteries (ZABs) hinges on resolving the persistent challenge of designing efficient and durable oxygen reduction reaction (ORR) catalysts. In this work, a nitrogen-doped carbon-coated Cu/Fe2N (Cu/Fe2N@NC) core-shell nanostructured catalyst was synthesized using DC arc plasma technique and subsequent nitridation treatment. The Mott-Schottky heterojunction formed by highly conductive Cu nanoparticles and surrounding Fe2N nanoparticles enabled spontaneous electron transfer, promoting rapid electron delivery from active sites toward oxygen-containing intermediates. The as-prepared Cu/Fe2N@NC catalyst shows outstanding ORR catalytic activity, reaching an onset potential of 0.97 V and delivering a half-wave potential of 0.83 V that approaches commercial Pt/C performance. When employed as a cathode catalyst for liquid ZABs, Cu/Fe2N@NC exhibits superior electrochemical performance over the Pt/C reference catalyst, delivering an open-circuit voltage of 1.50 V, a specific capacity of 786.7 mAh g-1 and a peak power density of 153 mW cm-2. This work demonstrates the potential of non-precious metal Mott-Schottky heterojunction catalysts for efficient and stable ORR performance.