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Boron nitride nanotubes (BNNTs) are promising nanomaterials for drug delivery due to their remarkable mechanical and electrical properties. BNNTs use nanopumping technique to transport drug molecules to target sites when subjected to an external force, such as an electric field or mechanical forces. Despite numerous efforts to investigate BNNTs/biomolecules interactions, the impact of atomic‐scale intrinsic characteristics of BNNT on drug delivery efficiency and delivery time is not well understood. To investigate this, we use molecular dynamics simulations (MD) to develop two simulation models: one with defective BNNT and another with a non‐defective (pristine) BNNT. Here, the fullerene molecule (C20) is introduced into BNNT and transported towards target cells. Our results show that vacancy defects can significantly impact the effectiveness of the nanopumping process. In pristine BNNTs, drug molecules move primarily by translation motion. However, the presence of vacancy defects and their concentration in BNNTs can affect the translation motion of drug molecules. We show that the judicious selection of oscillation frequency and amplitude of Cu tips is important to achieve efficient drug transport. This work provides new insights into the role of structural defects and oscillation on the drug transport efficiency of C20 molecules in BNNT using the nanopumping mechanism. [ABSTRACT FROM AUTHOR]

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A novel lactate biosensor based on a yttrium oxide/boron nitride (Y2O3/BN) nanocomposite modified electrode was developed. The BN nanosheets provided a supporting matrix for the Y2O3 nanoparticles, combining their synergistic properties for electrochemical biosensing. The Y2O3/BN nanocomposite provided high surface area and excellent electrocatalytic effects, promoting the oxidation of hydrogen peroxide generated from lactate oxidase catalyzed lactate oxidation. The Y2O3/BN modified biosensor showed wide linear range from 0.005 to 500 μM, low detection limit of 2 nM, high sensitivity of 1.23 μA/μM, good reproducibility with 3.2 % RSD, and long-term stability over 56 days. The biosensor could detect lactate levels in athlete sweat samples with high accuracy and correlation to standard methods, distinguishing changes in sweat lactate corresponding to different exercise intensities. The nanocomposite modified biosensor showed potential for non-invasive, real-time monitoring of exercise levels and fatigue status based on sweat lactate detection in athletic training applications.

The functionalization of additive manufacturing (AM) powders with nucleating particles has the potential to alter the grain structure, and hence the mechanical properties of 3D printed structures. We have investigated use of hexagonal boron nitride (BN) nanosheets to modify the microstructure of Ti parts produced by laser-based powder bed fusion (PBF-LB). The components were 3D printed from commercially pure titanium (cp-Ti) powders coated with small amounts (1.5 vol% ≈ 0.77 wt%) of BN nanosheets. As a comparison, pure cp-Ti parts were also built under the same processing conditions. Small- and wide-angle X-ray scattering (SAXS-WAXS) analysis of the 3D printed test structures revealed that BN addition significantly refined the α-Ti grain size and randomized the α-Ti texture. It was observed that grain-refined Ti-BN samples were harder and more brittle than their pure cp-Ti counterparts. This research provides new insights for grain refining using functional powder feedstocks with relatively simple powder pre-processing, and may be applied more broadly in laser-based metal AM.

Epitaxial lift-off (ELO) of high-quality GaN layers allows for integration with a variety of materials enabling improved performance, reduced costs, and development of new electronics. Of the ELO technologies, two-dimensional (2D) material-based lift-off offers great promise but is still in the early stages of development and has yet to demonstrate the scale and yield of other ELO technologies. Here, we demonstrate the potential of this process's scalability, speed, and yield through epitaxial growth and lift-off of 4-in. GaN films using a 2D boron nitride (BN) van der Waals (vdW) buffer layer. Since the BN layer acts as the growth template and the mechanical release layer, both the quality and adhesion of the GaN layer are correlated with the BN morphology and uniformity. Detailed spectroscopic mapping demonstrates excellent BN uniformity, which translates into growth of high-quality GaN as shown in mapping of the x-ray rock curves (XRCs), atomic force microscopy, and photoluminescence. Scanning transmission electron microscopy and electron energy loss spectroscopy reveal abrupt chemically distinct interfaces between the sapphire, BN, and AlN/GaN layers essential for efficient lift-off. Combined with the BN/GaN vdW heterostructure, Ni spalling is used to efficiently lift-off and transfer a full 4-in. GaN layer. Post transfer characterization of a 1.9 μm thick GaN layer transferred to a SiO2/Si wafer shows a very minimal change in the XRC and photoluminescence. Strain measurements before and after transfer show that the process fully relaxes residual strain formed in the GaN during high-temperature growth. This work highlights the potential for industry scalability of an exciting 2D material-based lift-off technology, which can facilitate higher power and more efficient radio frequency devices. [ABSTRACT FROM AUTHOR]

Integration of hexagonal boron nitride (h-BN) with plasmonic nanostructures that possess nanoscale field confinement will enable unusual properties; hence, the manipulation and understanding of the light interactions are highly desirable. Here, we demonstrate the surface plasmonic coupling of Au nanoparticles (ANPs) with ultrathin h-BN nanosheets (BNNS) in nonspecific nanocomposites leading to a great enhancement of the Raman signal of E2g in both experimental and theoretical manner. The nanocomposites were fabricated from liquid-exfoliated atomically thin BNNS and diblock copolymer-based ANPs with excellent dispersion through a self-assembly approach. By precisely varying the size of ANPs from 3 to 9 nm, the Raman signal of BNNS was improved from 1.7 to 71. In addition, the underlying mechanism has been explored from the aspects of electromagnetic field coupling strength between the localized surface plasmons excited from ANPs and the surrounding dielectric h-BN layers, as well as the charge transfer at the BNNS/ANPs interfaces. Moreover, we also demonstrate its capability to detect dye molecules as a surface enhanced Raman scattering (SERS) substrate. This work provides a basis for the self-assembly of BNNS hierarchical nanocomposites allowing for plasmon-mediated modulation of their optoelectronic properties, thereby showing the great potential not only in the field of SERS but also in large-scale h-BN-based plasmonic devices. [ABSTRACT FROM AUTHOR]

Cubic boron nitride (c-BN), with a small 1.4% lattice mismatch with diamond, presents a heterostructure with multiple opportunities for electronic device applications. However, the formation of c-BN/diamond heterostructures has been limited by the tendency to form hexagonal BN at the interface. In this study, c-BN has been deposited on free standing polycrystalline and single crystal boron-doped diamond substrates via electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR-PECVD), employing fluorine chemistry. In situ x-ray photoelectron spectroscopy (XPS) is used to characterize the nucleation and growth of boron nitride (BN) films as a function of hydrogen gas flow rates during deposition. The PECVD growth rate of BN was found to increase with increased hydrogen gas flow. In the absence of hydrogen gas flow, the BN layer was reduced in thickness or etched. The XPS results show that an excess of hydrogen gas significantly increases the percent of sp2 bonding, characteristic of hexagonal BN (h-BN), particularly during initial layer growth. Reducing the hydrogen flow, such that hydrogen gas is the limiting reactant, minimizes the sp2 bonding during the nucleation of BN. TEM results indicate the partial coverage of the diamond with thin epitaxial islands of c-BN. The limited hydrogen reaction is found to be a favorable growth environment for c-BN on boron-doped diamond. [ABSTRACT FROM AUTHOR]

The study aimed to develop a potential biomaterial for neuroregeneration by the electrospinning of the biocompatible polymer polyvinylidene fluoride (PVDF) with innovative functionalized boron nitride quantum dots (F-BNQDs) synthesized via green chemistry using the amino acid taurine as a functionalization. The F-BNQDs were characterized and were found to be 16-21 nm in diameter, showed good photoluminescent characteristics, and their elemental composition was confirmed by x-ray photoelectron spectroscopy, Fourier-transform infrared (FTIR), and ultraviolet spectroscopy. The PVDF with F-BNQDs was prepared at three different concentrations, and the resulting electrospun fibers were characterized by scanning electron microscopy, FTIR, thermogravimetric analysis, contact angle, biodegradation, water uptake, Schwann cell cytotoxicity, and cell behavior studies. The results of the study showed that the addition of F-BNQDs to PVDF resulted in enhanced mechanical properties, decreased contact angle, increased degradability, and water uptake. The lactate dehydrogenase assay revealed that 5% BN-PVDF had the lowest cytotoxicity. Fluroscent 4',6-diamidino-2-phenylindole (DAPI) staining showed that the increase in F-BNQD concentration up to 5% BN-PVDF enhanced cell behavior on the electrospun fibers. Therefore, the study concluded that 5% BN-PVDF would be suitable for further testing as a potential biomaterial for neuroregeneration in vivo. Highlights * Functionalized boron nitride quantum dots (F-BNQDs) were prepared using amino acid taurine. * The F-BNQDs were characterized and electrospun with polyvinylidene fluoride (PVDF). * The incorporation of F-BNQDs to PVDF has enhanced its physicochemical properties. * All samples showed a single [beta]phase PVDF. * Schwann cells showed excellent compatibility and cell adhesion on F-BNQDs/PVDF. KEYWORDS electrospinning, functionalized boron nitride quantum dots, PVDF, Schwann cells, taurine, 1 | INTRODUCTION Peripheral nerve injuries have the potential to cause total transection of the nerve, necessitating surgical intervention to enable the regrowth of axons from the injured site to [...]

[Display omitted] • Graphene and h-BN nanosheets was self-assembled on stainless steel to create stable heterostructured 2D nanocoatings. • These ultrathin 2D nanocoatings (< 30 nm) showed excellent corrosion resistance, with mechanisms revealed by electrochemical tests. • The nanocoatings offer multiple benefits like preventing reactions, labyrinth effect, curbing galvanic corrosion, and easing stress. In this study, an economic and controllable Marangoni self-assembly approach is designed to prepare the heterostructured nanocoatings (8–28 nm) consisting of alternately stacked mosaic nanosheets of hexagonal boron nitride (h -BN) and graphene. The resulting 2D nanocoatings exhibit a combination of advantageous properties, such as prevention of interfacial reactions, robust interfacial binding, a labyrinthine barrier effect, inhibition of galvanic corrosion, and alleviation of internal stress. The protective property of graphene/ h -BN heterostructured nanocoatings is studied through potentiodynamic polarization curves and electrochemical impedance spectroscopy, with the theoretical support of first-principles calculations. The corrosion current density of ≈28 nm-thick graphene/ h -BN multilayer coated stainless steel is 1.82 × 10−8 A cm−2, which decreases by an order of magnitude compared to that of an uncoated one, meanwhile, the corrosion potential increases from −0.192 to 0.023 V (increase: ≈0.215 V). The enhancement of anticorrosion performance of heterostructured nanocoatings can be attributed to the labyrinth barrier effect associated with highly ordered horizontal arrangement, effective coverage of metal substrates by mosaic multilayers, and suppressed galvanic corrosion effect by insulating BNNS monolayers. This study can shed much light on the effective solution of many stubborn issues confronted by the development of anticorrosive 2D nanocoatings. [ABSTRACT FROM AUTHOR]

[Display omitted] With the rapid development of large-scale clean energy, lithium-sulfur (Li-S) batteries are considered to be one of the most promising energy storage devices. In this manuscript, the polymetallic hetero-nanocrystal of iron nickel@cobalt nitride encapsulating into boron carbonitride nanotubes (Fe 0.64 Ni 0.36 @Co 5.47 N@BCN) was designed and optimized for use as a modified material for commercial polypropylene (PP) separators. The prepared Fe 0.64 Ni 0.36 @Co 5.47 N@BCN-12 hybrid material presents strong chemisorption and catalytic conversion capabilities, which endows the Fe 0.64 Ni 0.36 @Co 5.47 N@BCN-12//PP separator with enhanced polysulfide shuttling inhibition. The assembled Li-S cells with Fe 0.64 Ni 0.36 @Co 5.47 N@BCN-12//PP separators have minimized charge transfer resistance and faster redox kinetics. Additionally, cells with Fe 0.64 Ni 0.36 @Co 5.47 N@BCN-12//PP separator provide high reversible capacity of 674 mAh/g for 400 cycles at 0.5C and excellent cyclability for 1000 cycles at 2C with a low decay rate of 0.05 % per cycle. Therefore, this study provides a feasible functionalization route for improving the electrochemical performance of Li-S batteries through separator modification. [ABSTRACT FROM AUTHOR]

Biotite, an iron-rich mineral belonging to the trioctahedral mica group, is a naturally abundant layered material (LM) exhibiting attractive electronic properties for application in nanodevices. Biotite stands out as a non-degradable LM under ambient conditions, featuring high-quality basal cleavage—a significant advantage for van der Waals heterostructure (vdWH) applications. In this work, we present the micro-mechanical exfoliation of biotite down to monolayers (1Ls), yielding ultrathin flakes with large areas and atomically flat surfaces. To identify and characterize the mineral, we conducted a multi-elemental analysis of biotite using energy-dispersive spectroscopy mapping. Additionally, synchrotron x-ray fluorescence and infrared nano-spectroscopy were employed to probe its iron content and vibrational signature in few-layer form, respectively, with sensitivity to the layer number. We have also observed good morphological and structural stability in time (up to 12 months) and no important changes in their physical properties after thermal annealing processes in ultrathin biotite flakes. Conductive atomic force microscopy evaluated its electrical capacity, revealing an electrical breakdown strength of approximately 1 V nm−1. Finally, we explore the use of biotite as a substrate and encapsulating LM in vdWH applications. We have performed optical and magneto-optical measurements at low temperatures. We find that ultrathin biotite flakes work as a good substrate for 1L-MoSe2, comparable to hexagonal boron nitride flakes, but it induces a small change of the 1L-MoSe2 g -factor values, most likely due to natural impurities on its crystal structure. Furthermore, our results show that biotite flakes are useful systems to protect sensitive LMs such as black phosphorus from degradation for up to 60 days in ambient air. Our study introduces biotite as a promising, cost-effective LM for the advancement of future ultrathin nanotechnologies. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h-BN) ceramics exhibit exceptional thermal conductivity, yet integrating their anisotropic thermal properties into bulk ceramics remains challenging. This study investigates the impact of bimodal particle size distribution on the structure, thermal and mechanical properties of h-BN ceramics. Through DEM simulations and hot-pressing techniques, we demonstrate that incorporating large particles into fine ones significantly enhances the packing density, structural anisotropy and thermal properties of h-BN ceramics. The resulting high-purity h-BN ceramic prepared with 10 vol% large particles (10LBN) exhibits an Index of Orientation Preference (IOP) of −2780.57, surpassing that of ceramics without large particles (0LBN) at −1168.61. By regulating the structure, 10LBN h-BN ceramic show a notable increase of the in-plane thermal conductivity from 81.78 for 0LBN ceramics to 153.20 W/(m·K), along with a flexural strength of 58.21 MPa. Additionally, structural characterization and performance testing show that, compared to adding sintering additives, incorporating large plate-like h-BN particles offers greater benefits in optimizing the orientation structure and thermal conductivity of h-BN ceramics. These findings offer new insights for powder compaction using dual-sized plate-like particles and into the sintering of h-BN ceramics with tailored structural and thermal properties. [ABSTRACT FROM AUTHOR]

The miniaturization of electronic devices has led to an increase in power density and functional integration, resulting in rapid heat accumulation that adversely affects operational stability and service life. Dielectric composite films with excellent thermal conductivity and insulating properties are highly desired for addressing thermal management issues in electronic packaging applications. Hexagonal boron nitride (h-BN) is a promising filler for such composites due to its outstanding thermal conductivity, insulating properties, and chemical stability. However, the inherent platelike structure of h-BN causes significant anisotropy and poor miscibility with polymers, limiting the uniform conduction of heat. This study proposes a high-temperature sintering method that transforms flaky h-BN plates into irregular multifaceted particles. This transformation reduces thermal anisotropy and creates uniform heat conduction pathways. The resulting sintered BN/Epoxy (s-BN/EP) composite films exhibit exceptional thermal conductivity, with in-plane thermal conductivity increased by 36 % to 6.0 W m−1 K−1 and through-plane thermal conductivity increased by 39 % to 1.2 W m−1 K−1 compared to pristine h-BN/epoxy composites. Moreover, s-BN/EP films could maintain low dielectric constant (D k , 3.22) and dielectric loss (D f , 0.015) at 5 GHz. This innovative approach provides a significant advancement in the development of high-performance insulating polymer composites, offering a promising solution for thermal management in high-power-density electronic packaging. [Display omitted] [ABSTRACT FROM AUTHOR]

We perform molecular simulations to explore methane adsorption on carbon and boron nitride (BN) nanoscrolls, highlighting the impact of radius, pressure, and temperature on adsorption performance. Surprisingly, increasing nanoscroll layers, particularly in BN nanoscrolls, does not enhance methane adsorption but rather reduces release capacity. Our molecular simulations reveal a linear relationship between methane release and structural parameters of both carbon and BN nanoscrolls, with carbon nanoscrolls showing higher release independent of structure, while BN nanoscrolls' release varies with porosity, pore volume, and material density. The stability of this relationship is evident despite limited variability in structural parameters, pointing to elemental composition and molecular force fields as the key determinants of methane release behavior. At 30 MPa, BN nanoscrolls' volume adsorption marginally meets the DOE target, while carbon nanoscrolls show significant, yet insufficient, progress toward the same goal. Temperature studies indicate that lower temperatures benefit carbon nanoscrolls' adsorption and release but negatively impact BN nanoscrolls' release. Our results indicate that while both types of nanoscrolls can meet the DOE's targets for methane adsorption at low temperatures of 208 K and high pressures of 30 MPa, and have release capacities close to the targets, BN nanoscrolls, unlike carbon nanoscrolls, exhibit higher methane adsorption at low pressures of 0.1 MPa. This leads to more complex release phenomena for BN nanoscrolls. These findings provide critical insights, guiding the design and optimization of nanoscroll materials for enhanced methane adsorption and release in gas storage applications. [ABSTRACT FROM AUTHOR]

This study investigates the plastic deformation-induced fcc → hcp → bcc phase transition within nanograins in an ultra-strong gradient nanostructured surface layer on Fe45Mn35Cr10Co10 compositionally complex alloy (CCA), subjected to a single point cubic boron nitride turning process. High-resolution transmission electron microscope observations reveal a novel atomic movement mechanism of this transition following a unique Nishiyama-Wassermann orientation relationship. Unlike the previously validated Bogers-Burgers-Olson-Cohen model, which follows different orientation relationships and relies on two shear components, this study demonstrates that the phase transition in this CCA is cooperatively completed by two sets of half-partial dislocation dipoles and associated atom shuffling. Statement of Novelty A novel atomic mechanism of fcc → hcp → bcc phase transition, cooperatively completed by two sets of partial dislocation dipoles and atomic shuffling, provides potential implications for advanced structural materials. [ABSTRACT FROM AUTHOR]

We have investigated the potential of three dielectric materials to meet the future demands of green dielectrics: Polycaprolactone (PCL) thermoplastic, polyvinyl alcohol (PVA)‐carrageenan (CAR) crosslinked biopolymer, and boron nitride nanotubes (BNNTs) as a nano additive in PVA. Metal–insulator–metal (MIM) capacitors and organic thin film transistors (OTFT) were built with bilayer dielectric stacks of PVA‐CAR, PVA‐PCL, and PVA‐BNNT materials to examine their electrical properties. The PVA‐CAR layer uses a cyclic freeze thaw process to crosslink PVA and CAR for superior mechanical and electrical properties to either material alone. The PVA‐CAR MIM capacitors showed a dielectric constant of 23, which was found to be consistent with the extracted OTFT gate dielectric characteristics. Of the OTFT devices tested, PVA‐CAR OTFT showed highest device currents at low applied biases and produced an ON/OFF ratio of 104–105, both values were highest amongst the tested gate dielectrics. This material is therefore extremely promising for green electronics. The PVA‐PCL OTFT had very low leakage current and beneficial hydrophilic properties with comparable electrical properties to the commonly used organic material polytetrafluoroethylene. PVA‐BNNT MIM capacitors showed a low dielectric constant of 0.7, and the high resistivity makes this a promising material for shielding or substrates in high frequency applications. All three materials have the potential to fulfil different niches in a sustainable electronics future. [ABSTRACT FROM AUTHOR]

Thermal rectification is an asymmetric heat transfer process where directionally dependent transport occurs along a given axis. In this work, geometric parameters that govern thermal rectification in solids composed of various semiconducting materials were investigated utilizing metalattice data for seven materials with pore sizes ranging between 2 and 30 nm. Using numerical simulation, thermal rectification was calculated at different thermal biases in single material systems, including silicon, cubic boron nitride, and diamond, among others. The largest thermal rectification for each material was exhibited in bilayer sample stacks that were thermally matched (i.e., the thermal resistance of each layer in the stack is equal in either forward or reverse direction). Of the materials tested, diamond provided the highest thermal rectification for all cases, with its best case achieving a thermal rectification of 57.2%. This novel thermal functionality will find application in advanced applications for temperature regulation, including resonator systems where thermal effects may significantly alter and/or degrade performance. [ABSTRACT FROM AUTHOR]

In order to improve the photocatalytic performance of nano-noble metal materials, porous boron nitride nanosheets (h-BNNS) with high specific surface area were prepared by high temperature pyrolysis of the precursor using melamine and boric acid as raw materials. After vacuum impregnation of AgNO3, the nanosheets were added to polyvinylpyrrolidone (PVP) spinning solution. Ag/h-BNNS/PVP composite fiber film was prepared by electrospinning, and the composition, microstructure and photoelectrothermal properties of the composite fiber film were characterized. The Ag plasmon resonance effect significantly improves the visible light absorption and electron-hole pair separation efficiency of the composite fiber membrane. The results showed that silver nanoparticles (Ag NPs) were uniformly dispersed on the surface of the composite fibers, and the average particle size was less than 10 nm. In addition, the introduction of Ag NPs also improves the thermal stability of the membrane material. Based on the CO2 reduction model, the photocatalytic performance of the composite fiber membrane was investigated and tested. The results showed that the best photocatalytic activity of the composite fiber membrane was achieved when the calcination temperature was 250 ℃ and the Ag NPs content was 1.0% (CO yield was 300 μmol/(g·h)).The stability test showed that the CO yield of Ag/h-BNNS/PVP composite membrane was not less than 500 μmol/g after 10 cycles of use. Therefore, the efficient porous composite membrane catalyst prepared by doping Ag NPs to modify h-BNNS and loading Ag/h-BNNS composite particles in PVP fiber provides theoretical reference for future research on boron nitride based catalysts.

In order to exert the synergistic photocatalytic effect of nano-noble metal and polymer matrix, hexagonal boron nitride nanosheets (h-BNNS) were doped with C and O elements by RGO to obtain porous doped boron nitride materials (BCNO), and silver nanoparticles (Ag NPs) were loaded on BCNO matrix by hydrothermal method to prepare BCNO/Ag composites. The composition, microstructure and photocatalytic properties of the composites were characterized. The photocatalytic properties of BCNO/Ag composites were tested by reducing CO2 to CO as a reaction model. The results show that boron nitride modified by nonmetal doping still has a stable polycrystalline structure; After loading Ag NPs, the plasma resonance effect of Ag NPs not only significantly enhances the absorption ability of BCNO matrix to ultraviolet-visible light, but also improves the separation efficiency of its photogenerated carriers; During the preparation of composite materials, the composite material obtained with the addition of 3.0% silver and the calcination temperature of the composite sample at 130 ℃ exhibits the best photocatalytic performance, and the conversion rate of CO2 to CO is 4.68 μmol/（g·h）. Therefore, h-BNNS modified by doping can better stably load nano-precious metals, thus giving full play to the synergistic photocatalytic performance of Ag nanoparticle and BCNO, which provides a theoretical basis for the effective composite and performance research of organic-inorganic nanophotocatalyst.

Polycrystalline cubic boron nitride (PcBN) cutting tool materials were prepared by mixing cBN (85 wt.%) and TiN-Ti-Co (15 wt.%) micropowders under high temperature and ultra-high pressure. X-ray diffraction and scanning electron microscopy were employed to analyse the phase composition and microstructure of the composites. The effects of sintering temperature on the mechanical properties and cutting performance of the PcBN ceramics were also investigated. The results indicated that at the ultra-high pressure of 6GPa and temperatures ranging from 1400 to 1700°C, the PcBN composites consist of BN, TiN, TiB2 and Co phases. The PcBN sintered at 1700°C exhibited the most favourable comprehensive mechanical properties, including a flexural strength of 909MPa and microhardness of 36.8GPa. In addition, the cutting tool fabricated from the PcBN composite sintered at 1700°C showed superior cutting performances in testing with 40Cr mechanical parts.

Cr(VI) pollution poses great harm to the cyclic utilization of groundwater and surface water resources. Efficient adsorbent materials have great potential to change this situation and assist in the restoration of ecosystems. This work chooses porous boron nitride fibers (pBN) with stable physical and chemical properties as the matrix, 3‐aminopropyltriethoxysilane (APTES) as the coupling agent, and uses a one‐step crosslinking method to graft poly(allylamine hydrochloride) (PAH) onto pBN, forming pBN‐AS@PAH with fascinating Cr(VI) adsorption capacity. PAH is uniformly covered and modified on the surface of pBN, and the composite with high specific surface area (383.33 m2/g), large pore volume (0.37 cm3/g), and abundant amino groups. Its equilibrium adsorption capacity for Cr(VI) can reach up to 123.32 mg/g, and the adsorption behavior follows the quasi second‐order kinetic model and Langmuir model, indicating the chemical adsorption process of monolayer. The adsorption style belongs to a spontaneous exothermic process and has the optimal adsorption effect at a pH of ~2. Additionally, after cycling for 5 times, the decrease rate of adsorption capacity is less than 10 %, showing an excellent reusability. [ABSTRACT FROM AUTHOR]

The two-dimensional nanomaterials are characterized by their ultra-thin structure, diverse chemical functional groups, and remarkable anisotropic properties. Since its discovery in 2004, graphene has attracted significant scientific interest due to its potential applications in various fields, including electronics, energy systems, and biomedicine. In medicine, graphene is used for designing smart drug delivery systems, especially for antibiotics, and biosensing. Skin trauma is a prevalent dermatological condition that increasingly contributes to morbidities and mortalities, thus representing a significant health burden. During tissue damage, rapid skin repair is crucial to prevent blood loss and infection. Therefore, drugs used for skin trauma must possess antimicrobial and anti-inflammatory properties. Two-dimensional (2D) nanomaterials possess remarkable physical, chemical, optical, and biological characteristics due to their uniform shape, increased surface area, and surface charge. Graphene and its derivatives, transition-metal dichalcogenides (TMDs), black phosphorous (BP), hexagonal boron nitride (h-BN), MXene, and metal-organic frameworks (MOFs) are among the commonly used 2D nanomaterials. Moreover, they exhibit antibacterial and anti-inflammatory properties. This review presents a comprehensive discussion of the clinical approaches employed for wound healing treatment and explores the applications of commonly used 2D nanomaterials to enhance wound healing outcomes. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN), also known as white graphene, has recently gained larger attention due to its unique physical and chemical properties. Owing to its excellent thermal conductivity and stability, hBN has been reported as an effective filler in many polymers. This study explores the potential of hBN as a catalyst support and filler for olefin polymerization. We report the atomic layer deposition (ALD) of γ‐Al2O3 on hydroxyl‐functionalized hBN. The alumina precursor, methylaluminoxane, showed high selectivity, depositing Al species only on the B‐OH sites, while B−O‐O−B sites remained unreacted. The hBN/γ‐Al2O3 hybrid was characterized by Fourier transform infrared (FTIR) spectroscopy, X‐Ray diffraction and transmission electron microscopy (TEM). The deposition of the aluminum over the hBN sheets was confirmed. The hBN/γ‐Al2O3 was used as a support for metallocene catalysts. The supported catalyst complex was highly active and produced ethylene‐propylene polymers with molecular weights up to 10 times higher, as demonstrated by gel permeation chromatography (GPC) [ABSTRACT FROM AUTHOR]

Tremendous popularity is observed for multifunctional flexible electronics with appealing applications in intelligent electronic skins, human–machine interfaces, and healthcare sensing. However, the reported sensing electronics, mostly can hardly provide ultrasensitive sensing sensitivity, wider sensing range, and robust cycling stability simultaneously, and are limited of efficient heat conduction out from the contacted skin interface after wearing flexible electronics on human skin to satisfy thermal comfort of human skin. Inspired from the ultrasensitive tactile perception microstructure (epidermis/spinosum/signal transmission) of human skin, a flexible comfortably wearable ultrasensitive electronics is hereby prepared from thermal conductive boron nitride nanosheets‐incorporated polyurethane elastomer matrix with MXene nanosheets‐coated surface microdomes as epidermis/spinosum layers assembled with interdigitated electrode as sensing signal transmission layer. It demonstrates appealing sensing performance with ultrasensitive sensitivity (≈288.95 kPa−1), up to 300 kPa sensing range, and up to 20 000 sensing cycles from obvious contact area variation between microdome microstructures and the contact electrode under external compression. Furthermore, the bioinspired electronics present advanced thermal management by timely efficient thermal dissipation out from the contacted skin surface to meet human skin thermal comfort with the incorporated thermal conductive boron nitride nanosheets. Thus, it is vitally promising in wearable artificial electronic skins, intelligent human‐interactive sensing, and personal health management. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN) holds promise as a solid state, van der Waals host of single photon emitters for on‐chip quantum photonics. The B‐center defect emitting at 436 nm is particularly compelling as it can be generated by electron beam irradiation. However, the emitter generation mechanism is unknown, the robustness of the method is variable, and it has only been applied successfully to thick flakes of hBN (≫ 10 nm). Here, it is used in situ time‐resolved cathodoluminescence (CL) spectroscopy to investigate the kinetics of B‐center generation. It is shown that the generation of B‐centers is accompanied by quenching of a carbon‐related emission at ≈305 nm and that both processes are rate‐limited by electromigration of defects in the hBN lattice. It identifies problems that limit the efficacy and reproducibility of the emitter generation method and solve them using a combination of optimized electron beam parameters and hBN pre‐and postprocessing treatments. It is achieved B‐center quantum emitters in hBN flakes as thin as 8 nm, elucidate the mechanisms responsible for electron beam restructuring of quantum emitters in hBN, and gain insights toward the identification of the atomic structure of the B‐center quantum emitter. [ABSTRACT FROM AUTHOR]

Graphene is a unique platform for tunable opto‐electronic applications thanks to its linear band dispersion, which allows electrical control of resonant light‐matter interactions. Tuning the nonlinear optical response of graphene is possible both electrically and in an all‐optical fashion, but each approach involves a trade‐off between speed and modulation depth. Here, lattice temperature, electron doping, and all‐optical tuning of third‐harmonic generation are combined in a hexagonal boron nitride‐encapsulated graphene opto‐electronic device and demonstrate up to 85% modulation depth along with gate‐tunable ultrafast dynamics. These results arise from the dynamic changes in the transient electronic temperature combined with Pauli blocking induced by the out‐of‐equilibrium chemical potential. The work provides a detailed description of the transient nonlinear optical and electronic response of graphene, which is crucial for the design of nanoscale and ultrafast optical modulators, detectors, and frequency converters. [ABSTRACT FROM AUTHOR]

MXene is investigated as an electrode material for different energy storage systems due to layered structures and metal‐like electrical conductivity. Experimental results show MXenes possess excellent cycling performance as anode materials, especially at large current densities. However, the reversible capacity is relatively low, which is a significant barrier to meeting the demands of industrial applications. This work synthesizes N‐doped graphene‐like carbon (NGC) intercalated Ti3C2Tx (NGC‐Ti3C2Tx) van der Waals heterostructure by an in situ method. The as‐prepared NGC‐Ti3C2Tx van der Waals heterostructure is employed as sodium‐ion and lithium‐ion battery electrodes. For sodium‐ion batteries, a reversible specific capacity of 305 mAh g−1 is achieved at a specific current of 20 mA g−1, 2.3 times higher than that of Ti3C2Tx. For lithium‐ion batteries, a reversible capacity of 400 mAh g−1 at a specific current of 20 mA g−1 is 1.5 times higher than that of Ti3C2Tx. Both sodium‐ion and lithium‐ion batteries made from NGC‐Ti3C2Tx shows high cycling stability. The theoretical calculations also verify the remarkable improvement in battery capacity within the NGC‐Ti3C2O2 system, attributed to the additional adsorption of working ions at the edge states of NGC. This work offers an innovative way to synthesize a new van der Waals heterostructure and provides a new route to improve the electrochemical performance significantly. [ABSTRACT FROM AUTHOR]

Aluminium alloys are preferred in various fields, especially in the aviation and automotive sectors, due to their lightweight and durable nature. However, their usage is limited due to weak tribological properties such as low hardness and high adhesion tendency against steel. In order to overcome this deficiency, this study aimed to develop AA7075 matrix composites reinforced with BN and MXene. The productions were conducted by powder metallurgy method with these reinforcements in different ratios, both together and separately. The produced composites were characterized primarily by XRD and SEM analyses, followed by measurement of density and porosity values. Wear tests were conducted using the reciprocating ball-on-flat method, at a frequency of 3 Hz, a sliding distance of 100 m, and a stroke distance of 5 mm, with Inox steel ball. The highest improvement in wear rate was realized under 5 N load at 5 wt.% reinforcement ratios of 48% and 42% for BN and MXene, respectively. When 2 wt% BN and MXene reinforcements were applied together, the improvement rate remained around 34%. It can be said that BN and MXene show promising results by providing significant improvements compared to their counterparts in the literature, with MXene especially warranting further investigation. [ABSTRACT FROM AUTHOR]

The hydrogen storage and sensor properties of Cu-modified boron nitride nanocone (BNNC) structure were comprehensively investigated using the density functional theory method (DFT). By replacing nitrogen atoms with copper atoms on the BNNC structure, the hydrogen molecule's adsorption enthalpy and Gibbs free energy values were calculated as −48.6 and −16.9 kJ/mol, respectively. 4 Cu-doped BNNC structure achieved a notable hydrogen storage capacity of 5.38 wt%. The molecular dynamics calculations demonstrate that the structure modified with four Cu atoms maintains its dynamic stability. Furthermore, this study reveals that the desorption temperatures tend to rise with an increase in the number of adsorbed hydrogen molecules, and the average desorption temperature under 1 atm pressure is determined to be 332 K. The changes of work function values after hydrogen adsorption point out that the Cu-modified BNNC has Φ-sensor feature. Overall, Cu-modified BNNC structures show promising potential as hydrogen storage materials in ambient conditions. [Display omitted] • Cu modified BNNC structures can be used as a potential hydrogen storage material. • The gravimetric capacity for the Cu-BNNC cluster was determined to be 5.38 wt%. • Cu modified BNNC structures exhibit Φ sensor functionality against hydrogen. [ABSTRACT FROM AUTHOR]

Porous boron nitrides (PBN) offer the potential for hydrogen storage, yet struggle to adsorb H 2 even at extremely low temperatures and high pressures due to weak hydrogen binding. Previous studies indicate that doping heteroatoms onto BN substrate enhances its H 2 affinity, but microstructural changes, especially in pore structure, also crucially impact H 2 adsorption. In this study, we synthesized heteroatom-doped porous boron nitrides (HPBN-n-T) by adjusting nitrogen-to-boron source ratios (n) and calcination temperature (T). Comprehensive characterization revealed that heteroatom doping altered both the chemical composition and pore structure of HPBNs. Both heteroatom content and the highest microporosity are the key factors influencing the hydrogen storage performance, but the former and the latter play a more important role at low and room temperatures, respectively. HPBN-3-800 exhibits the strongest affinity for hydrogen (1.05 and 0.87 × 10−3 wt% g m−2) at low temperatures (77 K and 87 K) under 1 bar due to its high heteroatom content (5.56 at%). Meanwhile, HPBN-1-1000 demonstrates the highest affinity for hydrogen (1.18 × 10−3 wt% g m−2) at room temperature (298 K) under 130 bar owing to its highest microporosity (74.5%). In addition, HPBN-3-800 and HPBN-1-1000 also show the highest isosteric heat of adsorption (Q st), 7.55 and 7.53 kJ/mol respectively, confirming that increasing heteroatoms content and microporosity jointly enhance the affinity to hydrogen for HPBNs. DFT calculations further reveal that both heteroatoms and pore defects contribute to generating charge defects to enhance the interaction between the BN substrate and H 2 molecules. This study highlights the effect of heteroatom doping-induced chemical and textural variations on H 2 adsorption and offers insights into designing PBN materials for hydrogen storage via heteroatom doping. [Display omitted] • Heteroatom doping not only affects the chemical composition but also textural properties of HPBNs. • The heteroatom content and microporosity enhance the isosteric heat of adsorption of HPBNs and improve hydrogen storage performance by generating charge defects that enhance the interaction between BN and H 2. • HPBN-3-800, with high heteroatom doping, achieved H 2 uptake per SSA of 1.05 × 10⁻³ wt.% g m⁻2 (77 K, 1 bar), while HPBN-1-1000, with 74.5% microporosity, reached 0.54 × 10⁻³ wt.% g m⁻2 (298 K, 130 bar). [ABSTRACT FROM AUTHOR]

We screened 1651 carbon and boron nitride (BN) nanotubes to investigate methane release at 298 K and hydrogen release at 77 K through grand canonical ensemble Monte Carlo (GCMC) simulations. The effects of nanotube radius, density, and van der Waals spacing on the release quantities of these gases were explored. Our research shows that CH 4 release in C(40,40) and BN(40,40) nanotubes reaches a high of 0.15 g/g, below the DOE's 0.5 g/g target. Similarly, the best nanotubes for volumetric release, C(21,9) and BN(18,18), peak at 175 cm³/cm³, below the DOE target of 330 cm³/cm³. This suggests that internal adsorption within isolated nanotubes is insufficient to meet DOE targets, highlighting the need for optimization of inter-tube van der Waals spacing. For H 2 , C(40,39) and BN(40,40) nanotubes are optimal for weight release, achieving up to 12.19% at a pressure of 8 MPa. This surpasses the 2025 DOE benchmark of 5.5 wt%. Meanwhile, C(28,7) and BN(24,24) nanotubes are most suitable for volumetric release. The C(28,7) nanotube, recommended for H 2 storage, reaches a volumetric release quantity close to the DOE target of 0.04 kg/L at a van der Waals spacing of 1 nm. At pressures exceeding 2 MPa, the weight adsorption outside nanotubes accounts for 40–55% of the total, underscoring the pivotal role of extra-tube adsorption in gas storage capacity for both CH 4 and H 2. The results provide a foundation for the design of nanotube-based materials for efficient gas storage and release, with implications for clean energy applications. • C(40,39) and BN(40,40) excel in hydrogen release, exceeding 2025 DOE goals. • C(28,7) and BN(24,24) top for hydrogen volume; C(28,7) nears DOE target at 1 nm spacing. • Extra-tube adsorption accounts for over 40% of CH4 and H 2 storage at pressures above 2 MPa. [ABSTRACT FROM AUTHOR]

Excitons in MoSe2 and WSe2 monolayers encapsulated with hexagonal boron nitride have been studied using optical reflectance spectroscopy. The ground and excited states of A- and B-excitons have been studied at temperatures from liquid helium to room temperature. The lines of excitons A: , B: and their excited states А: , А: , and В: are clearly observed in the reflectance spectrum. The observed line shapes of the reflection spectrum of transition metal dichalcogenide monolayers depend on the thickness of the hexagonal boron nitride layers used in the structure and are in good agreement with the numerical simulation using the transfer matrix method. For the first time, the values of the reduced masses of B-excitons have been obtained from experimental data and the performed calculations of the exciton binding energy. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride is rapidly gaining interest as a platform for photonic quantum technologies, due to its two-dimensional nature and its ability to host defects deep within its large band gap that may act as room-temperature single-photon emitters. In this review paper we provide an overview of (1) the structure, properties, growth and transfer of hexagonal boron nitride; (2) the creationof colour centres in hexagonal boron nitride and assignment of defects by comparison with ab initio calculations for applications in photonic quantum technologies; and (3) heterostructure devices for the electrical tuning and charge control of colour centres that form the basis for photonic quantum technology devices. The aim of this review is to provide readers a summary of progress in both defect engineering and device fabrication in hexagonal boron nitride based photonic quantum technologies. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS2) and hexagonal boron nitride (h‐BN) monolayer, and h‐BN/WS2 heterojunction with low lattice mismatch is constructed using density functional theory (DFT). The band structures, density of states (DOS), charge density differences (CDD), work function (WF), adsorption energy and adsorption distance of h‐BN/WS2 heterojunction for six gases molecules (CO, CO2, NO, NO2, SO2, and H2S) are systematically discussed. Gas adsorption on one‐side and both‐sides of the heterojunction is considered. The results indicate that the band gap of the heterojunction is lower than that of h‐BN and WS2, indicating that the construction of heterojunction is beneficial for conductivity. For six gases, the adsorption energy of one‐sided adsorption is significantly greater than that of both‐sided adsorption, except for CO2 and NO. The adsorption of NO and NO2 introduces the magnetism into the system. Interestingly, the h‐BN/WS2 heterojunction demonstrates excellent selectivity for NO gas under one‐sided and both‐sided adsorption. The corresponding adsorption mechanism is explored. [ABSTRACT FROM AUTHOR]

Polar van der Waals (vdW) crystals, composed of atomic layers held together by vdW forces, can host phonon polaritons—quasiparticles arising from the interaction between photons in free-space light and lattice vibrations in polar materials. These crystals offer advantages such as easy fabrication, low Ohmic loss, and optical confinement. Recently, hexagonal boron nitride (hBN), known for having hyperbolicity in the mid-infrared range, has been used to explore multiple modes with high optical confinement. This opens possibilities for practical polaritonic nanodevices with subdiffractional resolution. However, polariton waves still face exposure to the surrounding environment, leading to significant energy losses. In this work, we propose a simple approach to inducing a hyperbolic phonon polariton (HPhP) waveguide in hBN by incorporating a low dielectric medium, ZrS2. The low dielectric medium serves a dual purpose—it acts as a pathway for polariton propagation, while inducing high optical confinement. We establish the criteria for the HPhP waveguide in vdW heterostructures with various thicknesses of ZrS2 through scattering-type scanning near-field optical microscopy (s-SNOM) and by conducting numerical electromagnetic simulations. Our work presents a feasible and straightforward method for developing practical nanophotonic devices with low optical loss and high confinement, with potential applications such as energy transfer, nano-optical integrated circuits, light trapping, etc. [ABSTRACT FROM AUTHOR]

2D orthorhombic palladium diselenide is attracting rapidly increased interest by virtue of its fascinating physical properties and feasibility of phase transformation. However, it remains a major challenge to produce ultrathin PdSe2 through a facile chemical route and control phase transformation because of its anisotropic structure with strong interlayer coupling. Here, the efficient synthesis of few‐layer PdSe2 nanosheets with large sizes using an electrochemical exfoliation approach is reported. Upon thermal annealing at 300–350 °C, the as‐exfoliated PdSe2 nanosheets transform into metallic phase PdSe2‐x, as verified by scanning transmission electron microscopy, Raman spectroscopy, and electrical characterizations. Simple encapsulation using hexagonal boron nitride (h‐BN) can effectively suppress the Se‐loss triggered phase transformation, so that a metal‐semiconductor junction is formed by local phase modification. The fabricated PdSe2 field‐effect transistors exhibit p‐type transport property, which is in stark contrast to electron‐dominated ambipolar transport of pristine PdSe2 devices. The combination of high‐resolution X‐ray photoelectron spectroscopy and cross‐sectional transmission electron microscopy analysis reveals that the modulation of carrier polarity in h‐BN encapsulated PdSe2 should arise from the p‐doping effect associated with the impact of interfacial condition. The study opens up a new route for future phase‐engineered electronics in PdSe2 and other 2D noble metal dichalcogenides materials. [ABSTRACT FROM AUTHOR]

This paper deals with the effect of hydroxylated boron nitride nanosheets (BNNS) incorporation on the microstructural and mechanical features of zirconia ceramics. Few-layered BNNS were synthesized via a simple hydroxide-assisted planetary ball milling exfoliation technique. 3 mol% yttria tetragonal zirconia polycrystal (3Y-TZP) with 2.5 vol% BNNS powders were prepared by an environmentally friendly process in water, and spark-plasma sintered at three temperatures to explore the in-situ reduction of the functionalized BNNS. An exhaustive study by (S)TEM techniques was performed to elucidate the influence of the sintering temperature on the matrix and the 3Y-TZP/BNNS interfaces, revealing that BNNS were homogeneously distributed throughout the matrix with an abrupt transition at 3Y-TZP/BNNS interfaces. BNNS effectively hindered slow crack growth, thus increasing the composite's crack growth resistance by about 30 %. A 1 MPa·m1/2 rising R-curve was also induced by crack bridging. [Display omitted] • Hydroxylated few-layer BNNS by hydroxide-assisted PBM exfoliation technique. • Rigid BNNS homogeneously distributed and preferentially aligned at the mesoscale. • No BN-zirconia interphases formation but abrupt transition at zirconia/BNNS interface. • BNNS inhibit slow crack growth of 3Y-TZP increasing the composite crack growth resistance. • Effective crack bridging by BNNS results in a 1 MPa·m1/2 rising R-curve. [ABSTRACT FROM AUTHOR]

Achieving laser-driven solid-state lighting with higher brightness and laser power density engenders new requirements for higher-performance phosphor conversion materials. In this study, a highly efficient and thermally conductive tellurite phosphor-in-glass (PIG) added with hexagonal boron nitride (h-BN) was prepared for high-power laser driving. Reduction in the thermal expansion coefficient and refractive index matching with phosphor were realized by two-component regulation of the tellurite glass, which contributed to an enhanced laser irradiation threshold and luminous efficiency of the PIG. Furthermore, the micron h-BN powder, which served as a heat dissipation material and light scattering center, was uniformly dispersed within the PIG by stirring, which increased the thermal conductivity of the composite by 42 %. Microstructural characterization and XRD analysis indicated the ideal compound effect of h-BN and the integrity of the phosphor crystal phase. Notably, under irradiation with a high-power laser, the thermal stability of the composite material was significantly improved, and the luminous efficiency increased to 183.2 lm/W. Therefore, through component regulation and process optimization, the h-BN-added tellurite PIG acquired a high laser irradiation threshold and superior luminous efficiency, making it promising for applications in laser-driven white lighting. [ABSTRACT FROM AUTHOR]

Two-dimensional material hexagonal boron nitride (h-BN), and its one-dimensional thin strips, boron nitride nanoribbons (BNNRs) are electrically insulating with high thermal stability, making them excellent thermal conductors suitable for high-temperature application. BNNRs are wide bandgap semiconductors with bandgaps ranging from 4 to 6 eV. This study investigates the electronic properties of BNNRs with single vacancy defects in armchair and zigzag configurations. The nearest-neighbour tight-binding model and numerical method were used to simulate the electronic properties of BNNRs with a single vacancy, including band structure and local density of states. The alpha and beta matrices were adjusted to account for missing boron or nitrogen atoms. Furthermore, a small perturbations were introduced to model the effects of impurities and edge imperfections. The simulation result from this work was compared with pristine BNNRs to examine the impact of a single vacancy on their electronic properties. The findings reveal that both armchair and zigzag BNNRs with single vacancy defects exhibit distorted band structures and local density of states due to the delocalization of pz orbitals. The valence bands show a higher concentration of nitrogen, while the conduction bands are richer in boron. These findings provide insights into how vacancy defects and edge perturbations can influence the electronic properties of BNNRs, which can guide the design and optimization of BNNR-based electronic devices in future research. [ABSTRACT FROM AUTHOR]

Highlights As the energy demand continuously increases, polymer‐based materials have attracted much attention for energy storage systems as dielectric capacitors due to their higher power density and charge–discharge rate than lithium‐ion batteries and supercapacitors. However, it is necessary to increase the energy density of dielectric capacitors. In this context, poly(vinylidene fluoride‐co‐hexafluoropropylene), PVDF‐HFP, matrix nanocomposites are produced by solution casting method reinforced with hexagonal boron nitride (hBN) nanoparticles and silane‐modified boron nitride nanosheets ‐BNNSs‐ (BNNS‐VTS) up to 10 wt.% filler content. The effects of filler content and surface modification of hBN/BNNSs on PVDF‐HFP matrix nanocomposites' microstructure, phase evolution, crystalization behavior, dielectric properties, and energy storage performance are discussed. 4% hBN/PVDF‐HFP nanocomposite demonstrates 641 MV·m−1 of breakdown strength and 23.2 J·cm−3 of discharged energy density due to hexagonal boron nitride's excellent electrical insulating behavior. The achieved values are 3.0 and 10.5 times superior to the values of the neat thin film, respectively, and they are noteworthy among hBN‐ or BNNS‐reinforced PVDF‐based nanocomposites, even in multi‐layered structures. Furthermore, 4% hBN/PVDF‐HFP presents a giant charge–discharge energy efficiency (92%). It is thus demonstrated that hBN/PVDF‐HFP nanocomposites hold a great potential to be used in energy storage applications as flexible and lightweight dielectric capacitors. PVDF‐HFP matrix nanocomposites for electrical energy storage as flexible dielectric capacitors hBN NPs and silane‐modified BNNSs are reinforced into the matrix by 0–10 wt.%. The effects of filler content and surface modification of hBN/BNNSs are discussed. 4% hBN loading results in 23.2 J·cm−3 energy density and 92% efficiency at 641 MV·m−1 breakdown strength. Those metrics are relatively high in hBN‐ or BNNS‐reinforced PVDF‐based nanocomposites. [ABSTRACT FROM AUTHOR]

Highlights Interfacial and thermal conductivity issues of carbon fiber composites pose key challenges that restrict their application in the industry. Hence, we prepared an aqueous sizing agent modified with nanosol of boron nitride (BN) and carbon nanotube (CNT) hybrids using sol–gel method to synergistically enhance the interfacial performance and thermal conductivity of carbon fiber (CF) composites. Compared to the unsized CF composites, the interlaminar shear strength (ILSS), interfacial shear strength (IFSS), flexural strength and thermal conductivity of the sized composites were increased by 47.0%, 41.4%, 51.0% and 49.5%, respectively. This was attributed to the fact that the BN/CNT nanoparticles contained in the sizing agent increased the specific surface area of the fibers, enlarged the interfacial phase region for stress transfer, and facilitated the formation of strong chemical/physical interactions among the fibers and resin. Additionally, BN and CNT nanoparticles formed a three‐dimensional thermally conductive network on the fiber surface, which promoted the formation of a good heat transfer path between the fibers and resin. This work presents an effective strategy for fabricating CF composites with exceptional mechanical performance and thermal conductivity. A BN/CNT nanohybrid sol is prepared by sol–gel method. A sizing agent is fabricated by modifying WEP through BN/CNT nanohybridised sols. Sizing agent promotes a good thermal conductivity path between CF and resin. Sizing agent enhances the mechanical properties of CF composites. [ABSTRACT FROM AUTHOR]

The optoelectronic resistive random‐access memory (RRAM) with the integrated function of perception, storage and intrinsic randomness displays promising applications in the hardware level in‐sensor image cryptography. In this work, 2D hexagonal boron nitride based optoelectronic RRAM is fabricated with semitransparent noble metal (Ag or Au) as top electrodes, which can simultaneous capture color image and generate physically unclonable function (PUF) key for in‐sensor color image cryptography. Surface plasmons of noble metals enable the strong light absorption to realize an efficient modulation of filament growth at nanoscale. Resistive switching curves show that the optical stimuli can impede the filament aggregation and promote the filament annihilation, which originates from photothermal effects and photogenerated hot electrons in localized surface plasmon resonance of noble metals. By selecting noble metals, the optoelectronic RRAM array can respond to distinct wavelengths and mimic the biological dichromatic cone cells to perform the color perception. Due to the intrinsic and high‐quality randomness, the optoelectronic RRAM can produce a PUF key in every exposure cycle, which can be applied in the reconfigurable cryptography. The findings demonstrate an effective strategy to build optoelectronic RRAM for in‐sensor color image cryptography applications. [ABSTRACT FROM AUTHOR]

Light‐induced electron dynamics in monolayer hexagonal boron nitride is theoretically investigated under the influence of two‐color linearly‐polarized laser fields at frequencies ω and 2ω, by solving the time‐dependent Schrödinger equation with a tight‐binding model. In the weak field regime, it is confirm that the injection of ballistic current arises from the breakdown of time‐reversal symmetry. This phenomenon is attributed to quantum interference between two distinct excitation paths: a one‐photon (2ℏω) absorption path and a two‐photon (ℏω) absorption path. In a strong field regime, the analysis reveals that the two‐color laser fields may generate a substantial population imbalance within momentum space, consequently facilitating the injection of ballistic current even in a deeply off‐resonant regime. The findings demonstrate that a pronounced population imbalance exceeding 30% of excited electrons can be realized without relying on the ellipticity of the fields. This highlights the potential of linearly polarized light for efficient photovoltaic effects and valley population control in 2D systems and heterostructures. [ABSTRACT FROM AUTHOR]

Integrating free‐standing complex oxides with two‐dimensional (2D) materials has recently attracted great interest, due to the rich physics evolving from such structures. Enhancing and tuning the opto–electronic properties of these systems is of high importance for a multitude of applications, such as sensors, memory devices or optical communications. The electrostatic control of photoluminescence of monolayer MoS2 at room temperature via integration of free‐standing BaTiO3 (BTO), a ferroelectric perovskite oxide is presented. It is shown that the use of BTO leads to highly tunable exciton emission of MoS2 in a minimal range of gate voltages. Due to BTO's ferroelectric polarization‐induced doping, large peak emission shifts as well as a large and tunable A trion binding energy in the range of 40–100 meV are observed. These measurements are compared with those carried out when the BTO is replaced by a hexagonal boron nitride (hBN) dielectric layer, confirming BTO's superior gating properties and thus lower power consumption. Additionally, advantage of the ferroelectric switching of BTO is taken by fabricating devices where the BTO layer is decoupled from the gate electrode with a SiO2 layer. Choosing to isolate the BTO allows to induce large remanent behavior of MoS2’s excitonic features. [ABSTRACT FROM AUTHOR]

The structures, stability and electronic properties of the Ni-doped boron nitride tubular clusters (NiBm−1Nm), NH3 adsorption on the NiBm−1Nm (NH3NiBm−1Nm) and NH3 embedded into the NiBm−1Nm (NH3@NiBm−1Nm) (m = 48, 72 and 96) clusters have been investigated by using density functional theory. The results reveal that the diameters of the NiBm−1Nm clusters have almost no effect on the NH3 adsorption. The diameter of the NiB47N48 clusters is small enough to accommodate the NH3 molecules, and the appropriate diameter of the NiB71N72 clusters occurs to embed the NH3 molecules. The NH3 molecules prefer to adsorb on rather than embed into the NiBm−1Nm clusters. The charge transfer between the NH3 molecules and the NiBm−1Nm clusters is limit, in the range of 0.002–0.221 |e|. The adsorption between the NH3 molecules and the NiBm−1Nm clusters is chemical process. In a word, the curvature effects of the Ni-doped boron nitride nanotubes with various diameters on NH3 adsorption are restrict. [ABSTRACT FROM AUTHOR]

Low‐dimensional ferroelectricity is long sought for post‐Moore nanoscale nonvolatile memory. Although a series of 2D ferroelectrics (FEs) have been experimentally confirmed in recent years, the investigations on 1D FEs are still rare. Stimulated by the experimental synthesis of single‐walled carbon/boron nitride nanotubes endohedrally doped by metal halides, our first‐principles calculations show that they can be the candidates for 1D FEs with switchable polarizations vertical to the tube axis as the inner metal halides form into polar zigzag chains. The polarization can be reversed via the migration of metal ions inside the wall, crossing a small barrier around several meV. Similar 1D vertical ferroelectricity in ternary boron carbonitride hybrid nanotubes that have already been synthesized is also predicted. In comparison, herein, polarization is switched by rolling the whole nanotube, which can be realized by applying just a local electric field induced by a tip due to its structural rigidity, which is long sought but remains challenging in current explorations on either conventional or low‐dimensional FEs. [ABSTRACT FROM AUTHOR]