Resistive Switching in Bigraphene/Diamane Nanostructures Formed on a La3Ga5SiO14 Substrate Using Electron Beam Irradiation

Memristors, resistive switching memory devices, play a crucial role in the energy-efficient implementation of artificial intelligence. This study investigates resistive switching behavior in a lateral 2D composite structure composed of bilayer graphene and 2D diamond (diamane) nanostructures formed using electron beam irradiation. The resulting bigraphene/diamane structure exhibits nonlinear charge carrier transport behavior and a significant increase in resistance. It is shown that the resistive switching of the nanostructure is well controlled using bias voltage. The impact of an electrical field on the bonding of diamane-stabilizing functional groups is investigated. By subjecting the lateral bigraphene/diamane/bigraphene nanostructure to a sufficiently strong electric field, the migration of hydrogen ions and/or oxygen-related groups located on one or both sides of the nanostructure can occur. This process leads to the disruption of sp3 carbon bonds, restoring the high conductivity of bigraphene.

Theoretical Analysis of Riboflavin Adsorption on Hexagonal Boron Nitride for Drug Delivery Applications: Unveiling the Influence of Point Defects

This research delves into the intriguing realm of investigating the stability of vitamin B2 (riboflavin, Rf) on hexagonal boron nitride (h-BN), both in its pristine state and in the presence of vacancy defects, with the aim of harnessing their potential as carriers for drug delivery applications. Employing the density functional theory (DFT), we perform binding energy calculations and analyze the electronic structure of the BN@Rf system to unravel the nature of their interactions. Our comprehensive DFT calculations unequivocally demonstrate the spontaneous physical sorption of the drug onto the h-BN surface, facilitated by the formation of π-π stacking interactions. The adsorption energy spans a range from -1.15 to -4.00 eV per system, emphasizing the robust nature of the BN@Rf bonding. The results show that the HOMO and LUMO of riboflavin are located exactly in the region of the iso-alloxazine rings of riboflavin. This arrangement fosters the formation of π-π stacking between riboflavin and boron nitride, effectively facilitating the transfer of electron density within the BN@Rf system. Furthermore, our investigations reveal the significant impact of vacancy defects within the boron nitride lattice. These vacancies alter the behavior of the structure, prompting riboflavin to metamorphose from an electron donor to an electron acceptor, expanding our understanding of the interplay between boron nitride defects and riboflavin sorption. Therefore, it is imperative to exert meticulous oversight of the structural integrity of h-BN, given that the existence of vacancies may lead to a noticeable change in its adsorption properties. The obtained data could amplify our capacity to conceive and refine drug delivery h-BN-based systems.

The Temperature Dependence of the Hexagonal Boron Nitride Oxidation Resistance, Insights from First-Principle Computations

In this work, we studied the oxidation stability of h-BN by investigating different variants of its modification by -OH, -O- and -O-O- groups using an atomistic thermodynamics approach. We showed that up to temperatures of ~1700 K, oxygen is deposited on the surface of hexagonal boron nitride without dissociation, in the form of peroxide. Only at higher temperatures, oxygen tends to be incorporated into the lattice of hexagonal boron nitride, except in the presence of defects N_v, when the embedding occurs at all temperatures. Finally, the electronic and magnetic properties of the oxidized h-BN were studied.

Visualization of Swift Ion Tracks in Suspended Local Diamondized Few-Layer Graphene

In the present study we investigated the nanostructuring processes in locally suspended few-layer graphene (FLG) films by irradiation with high energy ions (Xe, 26-167 MeV). For such an energy range, the main channel of energy transfer to FLG is local, short-term excitation of the electronic subsystem. The irradiation doses used in this study are 1 × 10¹¹-5 × 10¹² ion/cm². The structural transformations in the films were identified by Raman spectroscopy and transmission electron microscopy. Two types of nanostructures formed in the FLG films as a result of irradiation were revealed. At low irradiation doses the nanostructures were formed preferably at a certain distance from the ion track and had the form of 15-35 nm "bunches". We assumed that the internal mechanical stress that arises due to the excited atoms ejection from the central track part creates conditions for the nanodiamond formation near the track periphery. Depending on the energy of the irradiating ions, the local restructuring of films at the periphery of the ion tracks can lead either to the formation of nanodiamonds (ND) or to the formation of AA' (or ABC) stacking. The compressive strain value and pressure at the periphery of the ion track were estimated as ~0.15-0.22% and ~0.8-1.2 GPa, respectively. The main novel results are the first visualization of ion tracks in graphene in the form of diamond or diamond-like rings, the determination of the main condition for the diamond formation (the absence of a substrate in combination with high ion energy), and estimates of the local strain at the track periphery. Generally, we have developed a novel material and have found how to control the film properties by introducing regions similar to quantum dots with the diamond interface in FLG films.

Synergistic Catalytic Effect of Ag and MgO Nanoparticles Supported on Defective BN Surface in CO Oxidation Reaction

Micron-sized supports of catalytically active nanoparticles (NPs) can become a good alternative to nanocarriers if their structure is properly tuned. Here, we show that a combination of simple and easily scalable methods, such as defect engineering and polyol synthesis, makes it possible to obtain Ag and MgO nanoparticles supported on defective hexagonal BN (h-BN) support with high catalytic activity in the CO oxidation reaction. High-temperature annealing in air of Mg-containing (<0.2 at.%) h-BN micropellets led to surface oxidation, the formation of hexagonal-shaped surface defects, and defect-related MgO NPs. The enhanced catalytic activity of Ag/MgO/h-BN materials is attributed to the synergistic effect of h-BN surface defects, ultrafine Ag and MgO NPs anchored at the defect edges, and MgO/Ag heterostructures. In addition, theoretical simulations show a shift in the electron density from metallic Ag towards MgO and the associated decrease in the negative charge of oxygen adsorbed on the Ag surface, which positively affects the catalytic activity of the Ag/MgO/h-BN material.

Single-step extraction of small-diameter single-walled carbon nanotubes in the presence of riboflavin

We propose a novel approach to disperse and extract small-diameter single-walled carbon nanotubes (SWCNTs) using an aqueous solution of riboflavin and Sephacryl gel. The extraction of small-diameter semiconducting SWCNTs was observed, regardless of the initial diameter distribution of the SWCNTs. Dispersion of SWCNTs occurs due to the adsorption of π-conjugated isoalloxazine moieties on the surface of small-diameter nanotubes and interactions between hydroxy groups of ribityl chains with water. During the SWCNT extraction, specific adsorption of riboflavin to SWCNTs leads to the minimization of interactions between the SWCNTs and gel media. Our experimental findings are supported by ab initio calculations demonstrating the impact of the riboflavin wrapping pattern around the SWCNTs on their interaction with the allyl dextran gel.

Diamane Oxide. Two-Dimensional Film with Mixed Coverage and a Variety of Electronic Properties

Here, we investigate stability of the diamane oxide films and show that various compositions can be realized depending on the precursors, temperature, and pressure. We demonstrate that the commonly used oxygen source in the H₂O form requires pressures of GPa order to fabricate the film, which is in full agreement with the experimental data. We show that different types of functional groups can tailor electronic properties of bilayer diamane. Finally, we study electronic property dependence on the film thickness, elucidating its connection with surface states.

Half-Metallic Heusler Alloy/MoS2 Based Magnetic Tunnel Junction

Integration of half-metallic materials and 2D spacers into vertical magnetoresistive spin valves may pave the way for effective low-power consumption storage and memory technologies. Driven by the recent successful growth of graphene/half-metallic Co₂Fe(Ge_1/2Ga_1/2) (CFGG) heterostructure, here we report a theoretical investigation of magnetic tunnel junction (MTJ) based on the ferromagnetic CFGG Heusler alloy and the MoS₂ spacer of different thicknesses. Using ab initio approach, we demonstrate that the inherent ferromagnetism of CFGG is preserved at the interface, while its half-metallicity is recovering within few atomic layers. Ballistic transport in CFGG/MoS₂/CFGG MTJ is studied within the nonequilibrium Green's function formalism, and a large magnetoresistance value up to ∼10⁵% is observed. These findings support the idea of effective spintronics devices based on half-metallic Heusler alloys and highly diversified transition metal dichalcogenide family.

Formation of Diamane Nanostructures in Bilayer Graphene on Langasite under Irradiation with a Focused Electron Beam

In the presented paper, we studied bilayer CVD graphene transferred to a langasite substrate and irradiated with a focused electron beam through a layer of polymethyl methacrylate (PMMA). Changes in the Raman spectra and an increase in the electrical resistance of bigraphene after irradiation indicate a local phase transition associated with graphene diamondization. The results are explained in the framework of the theory of a chemically induced phase transition of bilayer graphene to diamane, which can be associated with the release of hydrogen and oxygen atoms from PMMA and langasite due to the "knock-on" effect, respectively, upon irradiation of the structure with an electron beam. Theoretical calculations of the modified structure of bigraphene on langasite and the experimental evaluation of sp³-hybridized carbon fraction indicate the formation of diamane nanoclusters in the bigraphene irradiated regions. This result can be considered as the first realization of local tunable bilayer graphene diamondization.

A New Insight into the Mechanisms Underlying the Discoloration, Sorption, and Photodegradation of Methylene Blue Solutions with and without BNOx Nanocatalysts

Methylene blue (MB) is widely used as a test material in photodynamic therapy and photocatalysis. These applications require an accurate determination of the MB concentration as well as the factors affecting the temporal evolution of the MB concentration. Optical absorbance is the most common method used to estimate MB concentration. This paper presents a detailed study of the dependence of the optical absorbance of aqueous methylene blue (MB) solutions in a concentration range of 0.5 to 10 mg·L^-1. The nonlinear behavior of optical absorbance as a function of MB concentration is described for the first time. A sharp change in optical absorption is observed in the range of MB concentrations from 3.33 to 4.00 mg·L^-1. Based on the analysis of the absorption spectra, it is concluded that this is due to the formation of MB dimers and trimers in the specific concentration range. For the first time, a strong, thermally induced discoloration effect of the MB solution under the influence of visible and sunlight was revealed: the simultaneous illumination and heating of MB solutions from 20 to 80 °C leads to a twofold decrease in the MB concentration in the solution. Exposure to sunlight for 120 min at a temperature of 80 °C led to the discoloration of the MB solution by more than 80%. The thermally induced discoloration of MB solutions should be considered in photocatalytic experiments when tested solutions are not thermally stabilized and heated due to irradiation. We discuss whether MB is a suitable test material for photocatalytic experiments and consider this using the example of a new photocatalytic material-boron oxynitride (BNO_x) nanoparticles-with 4.2 and 6.5 at.% of oxygen. It is shown that discoloration is a complex process and includes the following mechanisms: thermally induced MB photodegradation, MB absorption on BNO_x NPs, self-sensitizing MB photooxidation, and photocatalytic MB degradation. Careful consideration of all these processes makes it possible to determine the photocatalytic contribution to the discoloration process when using MB as a test material. The photocatalytic activity of BNO_x NPs containing 4.2 and 6.5 at.% of oxygen, estimated at ~440 μmol·g^-1·h^-1. The obtained results are discussed based on the results of DFT calculations considering the effect of MB sorption on its self-sensitizing photooxidation activity. A DFT analysis of the MB sorption capacity with BNO_x NPs shows that surface oxygen defects prevent the sorption of MB molecules due to their planar orientation over the BNO_x surface. To enhance the sorption capacity, surface oxygen defects should be eliminated.

The Role of Structural Defects in the Growth of Two-Dimensional Diamond from Graphene

The presented work is devoted to the study of the formation of the thinnest diamond film (diamane). We investigate the initial stages of diamond nucleation in imperfect bilayer graphene exposed by the deposition of H atoms (chemically induced phase transition). We show that defects serve as nucleation centers, their hydrogenation is energy favorable and depends on the defect type. Hydrogenation of vacancies facilitates the binding of graphene layers, but the impact wanes already at the second coordination sphere. Defects influence of 5|7 is lower but promotes diamondization. The grain boundary role is similar but can lead to the final formation of a diamond film consisting of chemically connected grains with different surfaces. Interestingly, even hexagonal and cubic two-dimensional diamonds can coexist together in the same film, which suggests the possibility of obtaining a new two-dimensional polycrystal unexplored before.

Edges in bilayered h-BN: insights into the atomic structure

This study is devoted to the study of the edges of bilayered h-BN, whose atomic structure was previously generally unknown. It is shown that the edges tend to connect regardless of the edge cut. A defectless connection can be expected only in the case of a zigzag edge, while in other cases a series of tetragonal and octagonal defects will be formed. This result was obtained by carrying out an analogy between the edge of bilayered h-BN and the interface of monolayer h-BN. Information on the structure and energetics of closed edges allowed us to predict the shape of holes in h-BN, which agreed with the reference experimental data. Finally, it is shown that the closed edges do not create electronic states in the band gap, thus not changing the dielectricity of h-BN.

Recent Progress in Fabrication and Application of BN Nanostructures and BN-Based Nanohybrids

Due to its unique physical, chemical, and mechanical properties, such as a low specific density, large specific surface area, excellent thermal stability, oxidation resistance, low friction, good dispersion stability, enhanced adsorbing capacity, large interlayer shear force, and wide bandgap, hexagonal boron nitride (h-BN) nanostructures are of great interest in many fields. These include, but are not limited to, (i) heterogeneous catalysts, (ii) promising nanocarriers for targeted drug delivery to tumor cells and nanoparticles containing therapeutic agents to fight bacterial and fungal infections, (iii) reinforcing phases in metal, ceramics, and polymer matrix composites, (iv) additives to liquid lubricants, (v) substrates for surface enhanced Raman spectroscopy, (vi) agents for boron neutron capture therapy, (vii) water purifiers, (viii) gas and biological sensors, and (ix) quantum dots, single photon emitters, and heterostructures for electronic, plasmonic, optical, optoelectronic, semiconductor, and magnetic devices. All of these areas are developing rapidly. Thus, the goal of this review is to analyze the critical mass of knowledge and the current state-of-the-art in the field of BN-based nanomaterial fabrication and application based on their amazing properties.

Electronic properties of graphene oxide: nanoroads towards novel applications

In this work, we suggest an approach to manipulate the electronic properties of graphene oxide in a controllable manner. We study graphene nanoroads paved inside graphene oxide using density functional calculations. We show that this patterning allows transforming an insulator, graphene oxide, into a semiconductor or metal depending on the orientation of the nanoroads and their magnetic state. As a semiconductor, patterned graphene oxide is characterized by notably low effective masses of charge carriers. Additionally, we demonstrate the possibility to force the transition from a semiconducting to a half-metallic state in a controllable manner, by application of an external electric field. We believe that this remarkable opportunity to combine and control the electronic and magnetic properties of a material within a single sheet of graphene oxide paves the way towards new applications of graphene-oxide-based devices in 2D optoelectronics and spintronics.

Optomechanical Properties of MoSe2 Nanosheets as Revealed by In Situ Transmission Electron Microscopy

Free-standing few-layered MoSe₂ nanosheet stacks optoelectronic signatures are analyzed by using light compatible in situ transmission electron microscopy (TEM) utilizing an optical TEM holder allowing for the simultaneous mechanical deformation, electrical probing and light illumination of a sample. Two types of deformation, namely, (i) bending of nanosheets perpendicular to their basal atomic planes and (ii) edge deformation parallel to the basal atomic planes, lead to two distinctly different optomechanical performances of the nanosheet stacks. The former deformation induces a stable but rather marginal increase in photocurrent, whereas the latter mode is prone to unstable nonsystematic photocurrent value changes and a red-shifted photocurrent spectrum. The experimental results are verified by ab initio calculations using density functional theory (DFT).

Nanohardness from First Principles with Active Learning on Atomic Environments

We propose a methodology for the calculation of nanohardness by atomistic simulations of nanoindentation. The methodology is enabled by machine-learning interatomic potentials fitted on the fly to quantum-mechanical calculations of local fragments of the large nanoindentation simulation. We test our methodology by calculating nanohardness, as a function of load and crystallographic orientation of the surface, of diamond, AlN, SiC, BC₂N, and Si and comparing it to the calibrated values of the macro- and microhardness. The observed agreement between the computational and experimental results from the literature provides evidence that our method has sufficient predictive power to open up the possibility of designing materials with exceptional hardness directly from first principles. It will be especially valuable at the nanoscale where the experimental measurements are difficult, while empirical models fitted to macrohardness are, as a rule, inapplicable.

A DFT study on magnetic interfaces based on half-metallic Co2FeGe1/2Ga1/2 with h-BN and MoSe2 monolayers

A large variety of recently predicted and synthesized 2D materials significantly broaden the capabilities of magnetic interface design for spintronic applications. Their diverse structural and electronic properties allow fine adjustment of interfacial interactions between the electrode and spacer materials providing robust and effective spin transport. Based on recent experimental results, here we present a theoretical study of novel interfaces formed by a half-metallic Co₂FeGe_1/2Ga_1/2 (CFGG) substrate with h-BN or MoSe₂ monolayer on its top. By means of the DFT approach, the structural, magnetic and electronic properties are studied for the Co- and FeGeGa termination of the CFGG surface. The observed large spin polarization in the vicinity of the interface and robust magnetization exhibit the potential of 2D materials/CFGG heterostructures for spintronic applications.

Semiconductor nanochannels in metallic carbon nanotubes by thermomechanical chirality alteration

[Figure: see text].

Amorphous MoSxOy/h-BNxOy Nanohybrids: Synthesis and Dye Photodegradation

Molybdenum sulfide is a very promising catalyst for the photodegradation of organic pollutants in water. Its photocatalytic activity arises from unsaturated sulfur bonds, and it increases with the introduction of structural defects and/or oxygen substitutions. Amorphous molybdenum sulfide (a-MoSxOy) with oxygen substitutions has many active sites, which create favorable conditions for enhanced catalytic activity. Here we present a new approach to the synthesis of a-MoSxOy and demonstrate its high activity in the photodegradation of the dye methylene blue (MB). The MoSxOy was deposited on hexagonal boron oxynitride (h-BNO) nanoflakes by reacting h-BNO, MoCl5, and H2S in dimethylformamide (DMF) at 250 °C. Both X-ray diffraction analysis and high-resolution TEM show the absence of crystalline order in a-MoSxOy. Based on the results of Raman and X-ray photoelectron spectroscopy, as well as analysis by the density functional theory (DFT) method, a chain structure of a-MoSxOy was proposed, consisting of MoS3 clusters with partial substitution of sulfur by oxygen. When a third of the sulfur atoms are replaced with oxygen, the band gap of a-MoSxOy is approximately 1.36 eV, and the valence and conduction bands are 0.74 eV and -0.62 eV, respectively (relative to a standard hydrogen electrode), which satisfies the conditions of photoinduced splitting of water. When illuminated with a mercury lamp, a-MoSxOy/h-BNxOy nanohybrids have a specific mass activity in MB photodegradation of approximately 5.51 mmol g-1 h-1, which is at least four times higher than so far reported values for nonmetal catalysts. The photocatalyst has been shown to be very stable and can be reused.

Two-Dimensional Diamond-Diamane: Current State and Further Prospects

Two-dimensional diamond, or diamane, is an ultrathin film with unique physical properties that combine the record values of the bulk crystal with the exciting features caused by the nanoscale nature. At the current stage of research, the diamane properties are mostly studied theoretically, and the main experimental efforts are directed at its synthesis. The latter is the trickiest problem since traditional methods involving the application of high pressure are not fully suitable due to the influence of surface effects. For diamane research, this poses a number of challenges, whose description is the main purpose and scope of this review. The paper also discusses the progress made so far and outlines the prospects for this field, at the crossroads of the timeless diamond and decade-old graphene.

Quantum Transport of the 2D Surface State in a Nonsymmorphic Semimetal

In a topological semimetal with Dirac or Weyl points, the bulk-boundary correspondence principle predicts a gapless edge mode if the essential symmetry is still preserved at the surface. The detection of such topological surface state has been considered as the fingerprint prove for crystals with nontrivial topological bulk band. On the contrary, it has been proposed that even with symmetry broken at the surface, a new surface band can emerge in nonsymmorphic topological semimetals. The symmetry reduction at the surface lifts the bulk band degeneracies and produces an unusual "floating" surface band with trivial topology. Here, we first report quantum transport probing to ZrSiSe thin flakes and directly reveal transport signatures of this new surface state. Remarkably, though topologically trivial, such a surface band exhibits substantial two-dimensional Shubnikov-de Haas quantum oscillations with high mobility, which signifies a new protection mechanism and may open applications for quantum computing and spintronic devices.

The Features of Phase Stability of GaN and AlN Films at Nanolevel

Recently, two-dimensional gallium and aluminum nitrides have triggered a vast interest in their tunable optical and electronic properties. Continuation of this research requires a detailed understanding of their atomic structure. Here, by using first-principles calculations we reported a systematic study of phase stability of 2D-GaN and 2D-AlN. We showed that the films undergo a phase transition from a graphene-like to a wurtzite structure with a thickness increase, whereas the early reported body-centered-tetragonal phase requires specific conditions for stabilization. Additionally, we studied how the functionalization of the surface can modify the film structure as exemplified by hydrogenation.

Nano-Thermodynamics of Chemically Induced Graphene-Diamond Transformation

Nearly 2D diamond, or diamane, is coveted as an ultrathin sp³ -carbon film with unique mechanics and electro-optics. The very thinness (≈h) makes it possible for the surface chemistry, for example, adsorbed atoms, to shift the bulk phase thermodynamics in favor of diamond, from multilayer graphene. Thermodynamic theory coupled with atomistic first principles computations predicts not only the reduction of required pressure (p/p_∞  > 1 - h₀ /h) but also the nucleation barriers, definitive for the kinetic feasibility of diamane formation. Moreover, the optimal adsorbent chair-pattern on a bilayer graphene results in a cubic diamond lattice, while for thicker precursors the adsorbent boat-structure tends to produce hexagonal diamond (lonsdaleite), if graphene is in AA' stacking to start with. As adsorbents, H and F are conducive to diamond formation, while Cl appears sterically hindered.

Young's Modulus and Tensile Strength of Ti3C2 MXene Nanosheets As Revealed by In Situ TEM Probing, AFM Nanomechanical Mapping, and Theoretical Calculations

Two-dimensional transition metal carbides, that is, MXenes and especially Ti₃C₂, attract attention due to their excellent combination of properties. Ti₃C₂ nanosheets could be the material of choice for future flexible electronics, energy storage, and electromechanical nanodevices. There has been limited information available on the mechanical properties of Ti₃C₂, which is essential for their utilization. We have fabricated Ti₃C₂ nanosheets and studied their mechanical properties using direct in situ tensile tests inside a transmission electron microscope, quantitative nanomechanical mapping, and theoretical calculations employing machine-learning derived potentials. Young's modulus in the direction perpendicular to the Ti₃C₂ basal plane was found to be 80-100 GPa. The tensile strength of Ti₃C₂ nanosheets reached up to 670 MPa for ∼40 nm thin nanoflakes, while a strong dependence of tensile strength on nanosheet thickness was demonstrated. Theoretical calculations allowed us to study mechanical characteristics of Ti₃C₂ as a function of nanosheet geometrical parameters and structural defect concentration.

On the Edge of Bilayered Graphene: Unexpected Atomic Geometry and Specific Electronic Properties

The tendency of bilayered graphene edges to connect with each other allows to create hollow sp²-hybridized material with specific electronic properties. However, the unknown geometry of the formed edges hinders further investigation. Here we show that a closed bigraphene edge can be represented as a connection of generally misoriented graphene domains with topological defects and can be further described by grain boundary theory. The energy dependence of closed edges of commensurate twisted bilayered graphene is derived for any twist angle and edge orientation. Our findings allow to predict what particular edge types appear in the bilayered graphene holes and explain the structure of the connected bilayered graphene edges, which are often observed in the experiment.

Stability and gas sensing properties of Ta2X3M8 (X = Pd, Pt; M = S, Se) nanoribbons: a first-principles investigation

One dimensional Ta2(Pd/Pt)3(S/Se)8 nanoribbons (TPS-NR) are considered as a promising material in nanoelectronics due to their intrinsic semiconducting electronic properties. In this article, we study the stability of TPS-NR by considering their oxidation process. Our calculations showed that the Ta2(Pd/Pt)3Se8 nanoribbons are more environmentally stable than Ta2(Pd/Pt)3S8-NR. We studied the thermodynamics of the formation of monovacancies and their impact on the electronic properties of TPS-NR. Additionally, the sensing properties of environmentally stable Ta2Pd3Se8 nanoribbons were investigated. The observed changes of the electronic structure and transport properties after the adsorption of CO, NH3 and NO2 molecules reveal the mechanisms of possible application of Ta2Pd3Se8 nanoribbons as a gas sensor. The electronic transport properties of the nanoribbons exhibit a notable response to the presence of gas molecules.

Insights into the regularity of the formation of 2D 3d transition metal monocarbides

Recently, several theoretical predictions have been made about 2D planar FeC, CoC, NiC, and CuC, while their bulk phases still remain unknown. Here, we present a generalization of the 2D family of 3d transition metal monocarbides (TMC) by searching for their stable configurations with DFT methods and an evolutionary algorithm. It is found that in the TMC row (TM = Sc-Cu) the tendency of 3D rocksalt phase formation is monotonously interchanged with 2D phase appearance, namely, planar orthorhombic TMC characterized by carbon dimers inside metal hexagons. Among them, orthorhombic CoC and FeC monocarbides would likely be formed rather than any other 2D metal carbide phase or metal/graphene interface.

Non-chemical fluorination of hexagonal boron nitride by high-energy ion irradiation

Two-dimensional materials such as hexagonal boron nitride (h-BN) and graphene have attracted wide attention in nanoelectronics and spintronics. Since their electronic characteristics are strongly affected by the local atomic structure, the heteroatom doping could allow us to tailor the electronic and physical properties of two-dimensional materials. In this study, a non-chemical method of heteroatom doping into h-BN under high-energy ion irradiation was demonstrated for the LiF/h-BN/Cu heterostructure. Spectroscopic analysis of chemical states on the relevant atoms revealed that 6% ± 2% fluorinated h-BN is obtained by the irradiation of 2.4 MeV Cu²⁺ ions with the fluence up to 10¹⁴ ions cm^-2. It was shown that the high-energy ion irradiation leads to a single-sided fluorination of h-BN by the formation of the fluorinated sp ³-hybridized BN.

Graphene/Half-Metallic Heusler Alloy: A Novel Heterostructure toward High-Performance Graphene Spintronic Devices

Graphene-based vertical spin valves (SVs) are expected to offer a large magnetoresistance effect without impairing the electrical conductivity, which can pave the way for the next generation of high-speed and low-power-consumption storage and memory technologies. However, the graphene-based vertical SV has failed to prove its competence due to the lack of a graphene/ferromagnet heterostructure, which can provide highly efficient spin transport. Herein, the synthesis and spin-dependent electronic properties of a novel heterostructure consisting of single-layer graphene (SLG) and a half-metallic Co₂ Fe(Ge_0.5 Ga_0.5 ) (CFGG) Heusler alloy ferromagnet are reported. The growth of high-quality SLG with complete coverage by ultrahigh-vacuum chemical vapor deposition on a magnetron-sputtered single-crystalline CFGG thin film is demonstrated. The quasi-free-standing nature of SLG and robust magnetism of CFGG at the SLG/CFGG interface are revealed through depth-resolved X-ray magnetic circular dichroism spectroscopy. Density functional theory (DFT) calculation results indicate that the inherent electronic properties of SLG and CFGG such as the linear Dirac band and half-metallic band structure are preserved in the vicinity of the interface. These exciting findings suggest that the SLG/CFGG heterostructure possesses distinctive advantages over other reported graphene/ferromagnet heterostructures, for realizing effective transport of highly spin-polarized electrons in graphene-based vertical SV and other advanced spintronic devices.

Adhesion of Single-Walled Carbon Nanotube Thin Films with Different Materials

Single-walled carbon nanotubes (SWCNTs) possess extraordinary physical and chemical properties. Thin films of randomly oriented SWCNTs have great potential in many opto-electro-mechanical applications. However, good adhesion of SWCNT films with a substrate material is pivotal for their practical use. Here, for the first time, we systematically investigate the adhesion properties of SWCNT thin films with commonly used substrates such as glass (SiO₂), indium tin oxide (ITO), crystalline silicon (C-Si), amorphous silicon (a-Si:H), zirconium oxide (ZrO₂), platinum (Pt), polydimethylsiloxane (PDMS), and SWCNTs for self-adhesion using atomic force microscopy. By comparing the results obtained in air and inert Ar atmospheres, we observed that the surface state of the materials greatly contributes to their adhesion properties. We found that the SWCNT thin films have stronger adhesion in an inert atmosphere. The adhesion in the air can be greatly improved by a fluorination process. Experimental and theoretical analyses suggest that adhesion depends on the atmospheric conditions and surface functionalization.

Plasma Surface Polymerized and Biomarker Conjugated Boron Nitride Nanoparticles for Cancer-Specific Therapy: Experimental and Theoretical Study

A new low-pressure plasma-based approach to activate the surface of BN nanoparticles (BNNPs) in order to facilitate the attachment of folate acid (FA) molecules for cancer-specific therapy is described. Plasma treatment of BNNPs (BNNPs^PT) was performed in a radiofrequency plasma reactor using ethylene and carbon dioxide monomers. The carboxyl groups deposited on the surface of BNNPs^PT were activated by N,N'-dicyclohexylcarbodiimide (DCC) and participated in the condensation reaction with ethylene diamine (EDA) to form a thin amino-containing layer (EDA-BNNP^PT). Then, the DCC-activated FA was covalently bonded with BNNPs^PT by a chemical reaction between amino groups of EDA-BNNPs^PT and carboxyl groups of FA. Density functional theory calculations showed that the pre-activation of FA by DCC is required for grafting of the FA to the EDA-BNNPs^PT. It was also demonstrated that after FA immobilization, the electronic characteristics of the pteridine ring remain unchanged, indicating that the targeting properties of the FA/EDA-BNNPs^PT nanohybrids are preserved.

Nonstoichiometric Phases of Two-Dimensional Transition-Metal Dichalcogenides: From Chalcogen Vacancies to Pure Metal Membranes

Two-dimensional (2D) membranes consisting of a single layer of Mo atoms were recently manufactured [ Adv. Mater. 2018 , 30 , 1707281 ] from MoSe₂ sheets by sputtering Se atoms using an electron beam in a transmission electron microscope. This is an unexpected result as formation of Mo clusters should energetically be more favorable. To get microscopic insights into the energetics of realistic Mo membranes and nonstoichiometric phases of transition-metal dichalcogenides (TMDs) M_aX_b, where M = Mo and W and X = S, Se, and Te, we carry out first-principles calculations and demonstrate that the membranes, which can be referred to as metallic quantum dots embedded into a semiconducting matrix, can be stabilized by charge transfer. We also show that an ideal neutral 2D Mo or W sheet is not flat but a corrugated structure, with a square lattice being the lowest-energy configuration. We further demonstrate that several intermediate nonstoichiometric phases of TMDs are possible as they have lower formation energies than pure metal membranes. Among them, the orthorhombic metallic 2D M₄X₄ phase is particularly stable. Finally, we study the properties of this phase in detail and discuss how it can be manufactured by the top-down approaches.

Transition Metal Chalcogenide Single Layers as an Active Platform for Single-Atom Catalysis

Among the main appeals of single-atom catalysts are the ultimate efficiency of material utilization and the well-defined nature of the active sites, holding the promise of rational catalyst design. A major challenge is the stable decoration of various substrates with a high density of individually dispersed and uniformly active monatomic sites. Transition metal chalcogenides (TMCs) are broadly investigated catalysts, limited by the relative inertness of their pristine basal plane. We propose that TMC single layers modified by substitutional heteroatoms can harvest the synergistic benefits of stably anchored single-atom catalysts and activated TMC basal planes. These solid-solution TMC catalysts offer advantages such as simple and versatile synthesis, unmatched active site density, and a stable and well-defined single-atom active site chemical environment. The unique features of heteroatom-doped two-dimensional TMC crystals at the origin of their catalytic activity are discussed through the examples of various TMC single layers doped with individual oxygen heteroatoms.

Crystallography-Derived Young's Modulus and Tensile Strength of AlN Nanowires as Revealed by in Situ Transmission Electron Microscopy

Aluminum nitride (AlN) has a unique combination of properties, such as high chemical and thermal stability, nontoxicity, high melting point, large energy band gap, high thermal conductivity, and intensive light emission. This combination makes AlN nanowires (NWs) a prospective material for optoelectronic and field-emission nanodevices. However, there has been very limited information on mechanical properties of AlN NWs that is essential for their reliable utilization in modern technologies. Herein, we thoroughly study mechanical properties of individual AlN NWs using direct,  in situ bending and tensile tests inside a high-resolution TEM. Overall, 22 individual NWs have been tested, and a strong dependence of their Young's moduli and ultimate tensile strengths (UTS) on their growth axis crystallographic orientation is documented. The Young's modulus of NWs grown along the [101̅1] orientation is found to be in a range 160-260 GPa, whereas for those grown along the [0002] orientation it falls within a range 350-440 GPa. In situ TEM tensile tests demonstrate the UTS values up to 8.2 GPa for the [0002]-oriented NWs, which is more than 20 times larger than that of a bulk AlN compound. Such properties make AlN nanowires a highly promising material for the reinforcing applications in metal matrix and other composites. Finally, experimental results were compared and verified under a density functional theory simulation, which shows the pronounced effect of growth axis on the AlN NW mechanical behavior. The modeling reveals that with an increasing NW width the Young's modulus tends to approach the elastic constants of a bulk material.

Mechanical, Electrical, and Crystallographic Property Dynamics of Bent and Strained Ge/Si Core-Shell Nanowires As Revealed by in situ Transmission Electron Microscopy

Research on electromechanical properties of semiconducting nanowires, including plastic behavior of Si nanowires and superb carrier mobility of Ge and Ge/Si core-shell nanowires, has attracted increasing attention. However, to date, there have been no direct experimental studies on crystallography dynamics and its relation to electrical and mechanical properties of Ge/Si core-shell nanowires. In this Letter, we in parallel investigated the crystallography changes and electrical and mechanical behaviors of Ge/Si core-shell nanowires under their deformation in a transmission electron microscope (TEM). The core-shell Ge/Si nanowires were bent and strained in tension to high limits. The nanowire Young's moduli were measured to be up to ∼191 GPa, and tensile strength was in a range of 3-8 GPa. Using high-resolution imaging, we confirmed that under large bending strains, Si shells had irregularly changed to the polycrystalline/amorphous state, whereas Ge cores kept single crystal status with the local lattice strains on the compressed side. The nanowires revealed cyclically changed electronic properties and had decent mechanical robustness. Electron diffraction patterns obtained from  in situ TEM, paired with theoretical simulations, implied that nonequilibrium phases of polycrystalline/amorphous Si and β-Sn Ge appearing during the deformations may explain the regarded mechanical robustness and varying conductivities under straining. Finally, atomistic simulations of Ge/Si nanowires showed the pronounced changes in their electronic structure during bending and the appearance of a conductive channel in compressed regions which might also be responsible for the increased conductivity seen in bent nanowires.

Holey single-walled carbon nanotubes for ultra-fast broadband bolometers

Although carbon nanotubes have already been demonstrated to be a promising material for bolometric photodetectors, enhancing sensitivity while maintaining the speed of operation remains a great challenge. Here, we present a holey carbon nanotube network, designed to improve the temperature coefficient of resistance for highly sensitive ultra-fast broadband bolometers. Treatment of carbon nanotube films with low-frequency oxygen plasma allows fine tuning of the electronic properties of the material. The temperature coefficient of resistance of our films is much greater than the reported values for pristine carbon nanotubes, up to -2.8% K^-1 at liquid nitrogen temperature. The bolometer prototypes made from the treated films demonstrate high sensitivity over a wide IR range, a short response time, smooth spectral characteristics and a low noise level.

Ultrasharp h-BN Nanocones and the Origin of Their High Mechanical Stiffness and Large Dipole Moment

We report on experimental synthesis and theoretical studies of ultrasharp BN-nanocones. Using scanning and transmission electron microscopy, the cone-like morphology of synthesized products was confirmed. Theoretical analysis of the dipole moment nature in h-BN nanocones reveals that the moment has contributions from the polarity of B-N bonds and electronic flexoelectric effect associated with a curved h-BN lattice. The latter phenomenon is predicted on the basis of the extension of the theory of flexoelectric effects in the h-BN lattice through establishing universality of the linear dependence of flexoelectric dipole moments on local curvature in various nano- h-BN networks (nanotubes and fullerenes). Our study of the atomic structure response and its polarization under deformation of nanocones with different apex angles shows the advantageous properties of cones with the smallest angles.

Nanostructuring few-layer graphene films with swift heavy ions for electronic application: tuning of electronic and transport properties

The morphology and electronic properties of single and few-layer graphene films nanostructured by the impact of heavy high-energy ions have been studied. It is found that ion irradiation leads to the formation of nano-sized pores, or antidots, with sizes ranging from 20 to 60 nm, in the upper one or two layers. The sizes of the pores proved to be roughly independent of the energy of the ions, whereas the areal density of the pores increased with the ion dose. With increasing ion energy (>70 MeV), a profound reduction in the concentration of structural defects (by a factor of 2-5), relatively high mobility values of charge carriers (700-1200 cm2 V-1 s-1) and a transport band gap of about 50 meV were observed in the nanostructured films. The experimental data were rationalized through atomistic simulations of ion impact onto few-layer graphene structures with a thickness matching the experimental samples. We showed that even a single Xe atom with energy in the experimental range produces a considerable amount of damage in the graphene lattice, whereas high dose ion irradiation allows one to propose a high probability of consecutive impacts of several ions onto an area already amorphized by the previous ions, which increases the average radius of the pore to match the experimental results. We also found that the formation of "welded" sheets due to interlayer covalent bonds at the edges and, hence, defect-free antidot arrays is likely at high ion energies (above 70 MeV).

Chirality transitions and transport properties of individual few-walled carbon nanotubes as revealed by in situ TEM probing

Physical properties of carbon nanotubes (CNTs) are closely related to the atomic structure, i.e. the chirality. It is highly desirable to develop a technique to modify their chirality and control the resultant transport properties. Herein, we present an in situ transmission electron microscopy (TEM) probing method to monitor the chirality transition and transport properties of individual few-walled CNTs. The changes of tube structure including the chirality are stimulated by programmed bias pulses and associated Joule heating. The chirality change of each shell is analyzed by nanobeam electron diffraction. Supported by molecular dynamics simulations, a preferred chirality transition path is identified, consistent with the Stone-Wales defect formation and dislocation sliding mechanism. The electronic transport properties are measured along with the structural changes, via fabricating transistors using the individual nanotubes as the suspended channels. Metal-to-semiconductor transitions are observed along with the chirality changes as confirmed by both the electron diffraction and electrical measurements. Apart from providing an alternative route to control the chirality of CNTs, the present work demonstrates the rare possibility of obtaining the dynamic structure-properties relationships at the atomic and molecular levels.

Photocatalysis with Pt-Au-ZnO and Au-ZnO Hybrids: Effect of Charge Accumulation and Discharge Properties of Metal Nanoparticles

Metal-semiconductor hybrid nanomaterials are becoming increasingly popular for photocatalytic degradation of organic pollutants. Herein, a seed-assisted photodeposition approach is put forward for the site-specific growth of Pt on Au-ZnO particles (Pt-Au-ZnO). A similar approach was also utilized to enlarge the Au nanoparticles at epitaxial Au-ZnO particles (Au@Au-ZnO). An epitaxial connection at the Au-ZnO interface was found to be critical for the site-specific deposition of Pt or Au. Light on-off photocatalysis tests, utilizing a thiazine dye (toluidine blue) as a model organic compound, were conducted and confirmed the superior photodegradation properties of Pt-Au-ZnO hybrids compared to Au-ZnO. In contrast, Au-ZnO type hybrids were more effective toward photoreduction of toluidine blue to leuco-toluidine blue. It was deemed that photoexcited electrons of Au-ZnO (Au, ∼5 nm) possessed high reducing power owing to electron accumulation and negative shift in Fermi level/redox potential; however, exciton recombination due to possible Fermi-level equilibration slowed down the complete degradation of toluidine blue. In the case of Au@Au-ZnO (Au, ∼15 nm), the photodegradation efficiency was enhanced and the photoreduction rate reduced compared to Au-ZnO. Pt-Au-ZnO hybrids showed better photodegradation and mineralization properties compared to both Au-ZnO and Au@Au-ZnO owing to a fast electron discharge (i.e. better electron-hole seperation). However, photoexcited electrons lacked the reducing power for the photoreduction of toluidine blue. The ultimate photodegradation efficiencies of Pt-Au-ZnO, Au@Au-ZnO, and Au-ZnO were 84, 66, and 39%, respectively. In the interest of effective metal-semiconductor type photocatalysts, the present study points out the importance of choosing the right metal, depending on whether a photoreduction and/or photodegradation process is desired.

Construction of Polarized Carbon-Nickel Catalytic Surfaces for Potent, Durable, and Economic Hydrogen Evolution Reactions

Electrocatalytic hydrogen evolution reaction (HER) in alkaline solution is hindered by its sluggish kinetics toward water dissociation. Nickel-based catalysts, as low-cost and effective candidates, show great potentials to replace platinum (Pt)-based materials in the alkaline media. The main challenge regarding this type of catalysts is their relatively poor durability. In this work, we conceive and construct a charge-polarized carbon layer derived from carbon quantum dots (CQDs) on Ni₃N nanostructure (Ni₃N@CQDs) surfaces, which simultaneously exhibit durable and enhanced catalytic activity. The Ni₃N@CQDs shows an overpotential of 69 mV at a current density of 10 mA cm^-2 in a 1 M KOH aqueous solution, lower than that of Pt electrode (116 mV) at the same conditions. Density functional theory (DFT) simulations reveal that Ni₃N and interfacial oxygen polarize charge distributions between originally equal C-C bonds in CQDs. The partially negatively charged C sites become effective catalytic centers for the key water dissociation step via the formation of new C-H bond (Volmer step) and thus boost the HER activity. Furthermore, the coated carbon is also found to protect interior Ni₃N from oxidization/hydroxylation and therefore guarantees its durability. This work provides a practical design of robust and durable HER electrocatalysts based on nonprecious metals.

Compressive properties of hollow BN nanoparticles: theoretical modeling and testing using a high-resolution transmission electron microscope

Due to their excellent mechanical properties, nanoparticles have great potential as reinforcing phases in composite materials, friction modifiers in liquid lubricants, catalysts and drug-delivery agents. In the present study, the mechanical analysis of individual spherical hollow BN nanoparticles (BNNPs) using a combination of in situ compression tests inside a high-resolution transmission electron microscope (TEM) and theoretical modelling was conducted. It was found that BNNPs display high mechanical stiffness and a large value of elastic recovery. This enables the hollow BNNPs to exhibit considerably large cyclic deformation (up to 30% of the sphere's original external diameter) and to accumulate plastic deformation of approximately 30% of the total compression strain. Theoretical simulations allowed for elucidation of BNNPs' structural changes under compression at the atomic level and explained the origin of their high stiffness and large critical deformation values.

Phase diagram of carbon and the factors limiting the quantity and size of natural diamonds

Phase diagrams of carbon, and those focusing on the graphite-to-diamond transitional conditions in particular, are of great interest for fundamental and applied research. The present study introduces a number of experiments carried out to convert graphite under high-pressure conditions, showing a formation of stable phase of fullerene-type onions cross-linked by sp³-bonds in the 55-115 GPa pressure range instead of diamonds formation (even at temperature 2000-3000 K) and the already formed diamonds turn into carbon onions. Our results refute the widespread idea that diamonds can form at any pressure from 2.2 to 1000 GPa. The phase diagram built within this study allows us not only to explain the existing numerous experimental data on the formation of diamond from graphite, but also to make assumptions about the conditions of its growth in Earth's crust.

BN nanoparticle/Ag hybrids with enhanced catalytic activity: theory and experiments

BNNPs/Ag nanohybrids with an optimal amount of B₂O₃ demonstrated a higher catalytic activity.

Tuning of the Optical, Electronic, and Magnetic Properties of Boron Nitride Nanosheets with Oxygen Doping and Functionalization

Engineering of the optical, electronic, and magnetic properties of hexagonal boron nitride (h-BN) nanomaterials via oxygen doping and functionalization has been envisaged in theory. However, it is still unclear as to what extent these properties can be altered using such methodology because of the lack of significant experimental progress and systematic theoretical investigations. Therefore, here, comprehensive theoretical predictions verified by solid experimental confirmations are provided, which unambiguously answer this long-standing question. Narrowing of the optical bandgap in h-BN nanosheets (from ≈5.5 eV down to 2.1 eV) and the appearance of paramagnetism and photoluminescence (of both Stokes and anti-Stokes types) in them after oxygen doping and functionalization are discussed. These results are highly valuable for further advances in semiconducting nanoscale electronics, optoelectronics, and spintronics.

One-atom-thick 2D copper oxide clusters on graphene

The successful isolation and remarkable properties of graphene have recently triggered investigation of two-dimensional (2D) materials from layered compounds; however, one-atom-thick 2D materials without bulk layered counterparts are scarcely reported. Here we report the structure and properties of novel 2D copper oxide studied by experimental and theoretical methods. Electron microscopy observations reveal that copper oxide can form monoatomic layers with an unusual square lattice on graphene. Density functional theory calculations suggest that oxygen atoms at the centre of the square lattice stabilizes the 2D Cu structure, and that the 2D copper oxide sheets have unusual electronic and magnetic properties different from 3D bulk copper oxide.

Novel hybrid C/BN two-dimensional heterostructures

Here we present an investigation of new quasi-two-dimensional heterostructures based on the alternation of bounded carbon and boron nitride layers (C/BN). We carried out a theoretical study of the atomic structure, stability and electronic properties of the proposed heterostructures. Such ultrathin quasi-two-dimensional C/BN films can be synthesized by means of chemically induced phase transition by connection of the layers of multilayered h-BN/graphene van der Waals heterostructures, which is indicated by the negative phase transition pressure in the calculated phase diagrams (P, T) of the films. It was shown that the band gap value of the C/BN films spans the infrared and visible spectrum. We hope that the proposed films and fabrication method can be considered as a possible route to obtain nanostructures with a controllable band gap in wide energy range. This makes these materials potentially suitable for a variety of applications, including photovoltaics, photoelectronics and more.

Theoretical Investigation of the Interfaces and Mechanisms of Induced Spin Polarization of 1D Narrow Zigzag Graphene- and h-BN Nanoribbons on a SrO-Terminated LSMO(001) Surface

The structure of the interfaces and the mechanisms of induced spin polarization of 1D infinite and finite narrow graphene- and h-BN zigzag nanoribbons placed on a SrO-terminated La_1-xSr_xMnO₃ (LSMO) (001) surface were studied using density functional theory (DFT) electronic structure calculations. It was found that the π-conjugated nanofragments are bonded to the LSMO(001) surface by weak disperse interactions. The types of coordination of the fragments, the strength of bonding, and the rate of spin polarization depend upon the nature of the fragments. Infinite and finite graphene narrow zigzag nanoribbons are characterized by the lift of the spin degeneracy and strong spin polarization caused by interface-induced structural asymmetry and oxygen-mediated indirect exchange interactions with Mn ions of LSMO support. Spin polarization changes the semiconducting nature of infinite graphene nanoribbons to half-metallic state with visible spin-up density of states at the Fermi level. The h-BN nanoribbon binding energy is weaker than graphene nanoribbon ones with noticeably shorter interlayer distance. The asymmetry effect and indirect exchange interactions cause spin polarization of h-BN nanoribbon as well with formation of embedded states inside the band gap. The results show a possibility to use one-atom thick nanofragments to design LSMO-based heterostructures for spintronic nanodevices with h-BN as an inert spacer to develop different potential barriers.

Multifunctional Superelastic Foam-Like Boron Nitride Nanotubular Cellular-Network Architectures

Construction of cellular architectures has been expected to enhance materials' mechanical tolerance and to stimulate and broaden their efficient utilizations in many potential fields. However, hitherto, there have been rather scarce developments in boron nitride (BN)-type cellular architectures because of well-known difficulties in the syntheses of BN-based structures. Herein, cellular-network multifunctional foams made of interconnective nanotubular hexagonal BN (h-BN) architectures are developed using carbothermal reduction-assisted in situ chemical vapor deposition conversion from N-doped tubular graphitic cellular foams. These ultralight, chemically inert, thermally stable, and robust-integrity (supporting about 25,000 times of their own weight) three-dimensional-BN foams exhibit a 98.5% porosity, remarkable shape recovery (even after cycling compressions with 90% deformations), excellent resistance to water intrusion, thermal diffusion stability, and high strength and stiffness. They remarkably reduce the coefficient of thermal expansion and dielectric constant of polymeric poly(methyl methacrylate) composites, greatly contribute to their thermal conductivity improvement, and effectively limit polymeric composite softening at elevated temperatures. The foams also demonstrate high-capacity adsorption-separation and removal ability for a wide range of oils and organic chemicals in oil/water systems and reliable recovery under their cycling usage as organic adsorbers. These created multifunctional foams should be valuable in many high-end practical applications.

Mechanical properties and current-carrying capacity of Al reinforced with graphene/BN nanoribbons: a computational study

Record high values of Young's modulus and tensile strength of graphene and BN nanoribbons as well as their chemically active edges make them promising candidates for serving as fillers in metal-based composite materials. Herein, using ab initio and analytical potential calculations we carry out a systematic study of the mechanical properties of nanocomposites constructed by reinforcing an Al matrix with BN and graphene nanoribbons. We consider a simple case of uniform distribution of nanoribbons in an Al matrix under the assumption that such configuration will lead to the maximum enhancement of mechanical characteristics. We estimate the bonding energy and the interfacial critical shear stress at the ribbon/metal interface as functions of ribbon width and show that the introduction of nanoribbons into the metal leads to a substantial increase in the mechanical characteristics of the composite material, as strong covalent bonding between the ribbon edges and Al matrix provides efficient load transfer from the metal to the ribbons. Using the obtained data, we apply the rule of mixtures in order to analytically assess the relationship between the composite strength and concentration of nanoribbons. Finally, we study carbon chains, which can be referred to as the ultimately narrow ribbons, and find that they are not the best fillers due to their weak interaction with the Al matrix. Simulations of the electronic transport properties of the composites with graphene nanoribbons and carbyne chains embedded into Al show that the inclusion of the C phase gives rise to deterioration in the current carrying capacity of the material, but the drop is relatively small, so that the composite material can still transmit current well, if required.