Multilayer boron nitride nanosheets (BNNSs) are promising two-dimensional structure‒function enhancers due to their structural and mechanical similarity to multilayer graphene (MLG). However, challenges in scalable synthesis/preparation techniques and effective interfacial integration approaches for BNNSs have limited their application in ceramic-matrix composites. Herein, we report the cost-effective, large-scale production of high-quality MBNSs via three-roll milling and their incorporation into a dual-phase SiC matrix through a tailored interfacial modification strategy. These MBNS-dominated microstructures activated multiple synergistic toughening mechanisms, yielding an ~95% increase in flexural strength and an ~50% enhancement in fracture toughness. Additionally, the composite exhibited excellent electromagnetic absorption performance, achieving a minimum reflection loss (RL_min) of −52.59 dB at 1.22 mm and a maximum effective absorption bandwidth (EAB_max) of full Ku-band coverage (5.6 GHz) at 1.09 mm thickness. This work presents a scalable strategy for the fabrication of high-performance, structurally and functionally integrated composites, offering significant potential for advanced structural and electromagnetic applications.

To address the challenges of insufficient thermal resistance and high-temperature stability in current environmental barrier coating (EBC) bond coats above 1500 °C, this study successfully synthesized HfO₂–Al₂O₃–SiO₂ powders with a dispersion-strengthened structure for EBC bond coat raw material for spraying through a solid-phase synthesis method using HfO₂, Al₂O₃, and SiO₂ sol. The dispersion-strengthened structure with a microstructure of oxides (HfO₂ and Al₂O₃) dispersed in silicates (mullite and HfSiO₄) can be achieved by systematically adjusting the component molar ratios, synthesis temperature, and time. The synthesized raw powders underwent subsequent high-temperature hot-pressing sintering to form ceramic bulks, allowing for a comprehensive characterization of the intrinsic material properties, including thermal conductivity, coefficient of thermal expansion, mechanical performance, oxidation resistance at 1600 °C, and water‒oxygen corrosion resistance at 1300 °C. The investigation elucidates the property evolution and related mechanisms, conclusively demonstrating the viability of the HfO₂–Al₂O₃–SiO₂ system as an EBC bond coating material. Additional chemical compatibility tests with SiO₂ at 1500 °C further validated the dispersion-strengthened structure. Notably, oxidation resistance testing at 1600 °C revealed that Al₂O₃ could better capture SiO₂ generated by the decomposition of HfSiO₄ to form mullite, thus enhancing the high-temperature stability of the HfO₂–Al₂O₃–SiO₂ material, benefiting from its dispersion-strengthened structure. The present study establishes a robust theoretical foundation for the development of EBC bond coatings with exceptional high-temperature endurance exceeding 1500 °C.

Two-dimensional (2D) nanomaterials, such as graphene, MoS₂, and MAX, have attracted increasing research attention in recent years due to their unique structural and performance advantages. However, their complex production processes and equipment requirements are significant issues affecting their widespread use. Here, with an exfoliation strategy using three-roll milling, we present a simple, cost-effective, and extensible method to produce multilayer graphene, BN, MoS₂, and Ti₃AlC₂ nanosheets. The roller and phenolic resin created three kinds of forces on the layered 2D materials, i.e., shear forces, compressive forces, and adhesive forces, which exfoliated layered materials from their edges and surfaces into nanosheets. Subsequently, the exfoliated materials were ultrasonically washed with alcohol, treated with ultrasonic vibration, and centrifuged to obtain 2D nanomaterials. The easy operation and high yield are attractive for research based on the construction of high-performance 2D nanosheet-based devices at low cost. Herein, the obtained multilayer graphene and MoS₂ nanosheets were used as anode materials of sodium/potassium-ion batteries, respectively, to test their electrochemical properties. Better performances are obtained compared with their primary bulk materials.

Developing highly efficient and stable non-precious metal catalysts for water splitting is urgently required. In this work, we report a facile one-step molten salt method for the preparation of self-supporting Ni-doped Mo₂C on carbon fiber paper (Ni-Mo₂C_CB/CFP) for hydrogen evolution reaction (HER). The effects of nickel nitrate concentration on the phase composition, morphology, and electrocatalytic HER performance of Ni-doped Mo₂C@CFP electrocatalysts was investigated. With the continuous increase of Ni(NO₃)₂ concentration, the morphology of Mo₂C gradually changes from granular to flower-like, providing larger specific surface area and more active sites. Doping nickel (Ni) into the crystal lattice of Mo₂C largely reduces the impedance of the electrocatalysts and enhances their electrocatalytic activity. The as-developed Mo₂C-3 M Ni(NO₃)₂/CFP electrocatalyst exhibits high catalytic activity with a small overpotential of 56 mV at a current density of 10 mA·cm^-2. This catalyst has a fast HER kinetics, as demonstrated by a very small Tafel slope of 27.4 mV·dec^-1, and persistent long-term stability. A further higher Ni concentration had an adverse effect on the electrocatalytic performance. Density functional theory (DFT) calculations further verified the experimental results. Ni doping could reduce the binding energy of Mo-H, facilitating the desorption of the adsorbed hydrogen (H_ads) on the surface, thereby improving the intrinsic catalytic activity of Ni-doped Mo₂C-based catalysts. Nevertheless, excessive Ni doping would inhibit the catalytic activity of the electrocatalysts. This work not only provides a simple strategy for the facile preparation of non-precious metal electrocatalysts with high catalytic activity, but also unveils the influence mechanism of the Ni doping concentration on the HER performance of the electrocatalysts from the theoretical perspective.