Diamane, a two-dimensional diamond-like carbon phase, illustrates how computational materials science can anticipate structures and transformations later verified experimentally. This Perspective summarizes theoretical predictions and experimental observations of its stability, chemically driven diamondization, and property modulation through functionalization and orientation. We highlight how atomistic simulations refine the understanding of formation pathways and guide potential applications in electronics, photonics, and energy systems.

Materials for extreme environments require high strength yet ductile to tolerate catastrophic damage. Face-centered cubic (FCC) metals are typically ductile under stress, but single-crystal FCC iridium exhibits intrinsically brittle, limiting its wider applications. Great efforts on theoretical studies have attributed this to non-planar dislocation cores or impurities, while direct experimental evidence has remained elusive. Here we report that high-density, sessile Frank dislocation loops with zero-net Burgers vectors are the primary cause of the brittleness, identified through atomic-resolution scanning transmission electron microscopy. Through first-principles calculations, supported by discrete dislocation dynamics simulations, we reveal that these loops form via an energetically favorable transformation from mixed perfect dislocations under stress, a process unique to iridium among other FCC metals. The immobile loops act as potent barriers, drastically increasing yield strength and work hardening by impeding dislocation glide and consuming mobile dislocations. These decisive results not only deepen the understanding of the iridium brittleness, but also describe the existence of a new embrittlement mechanism inherent to the FCC lattice and not previously described in the literature. The latter may enable novel routes for property tuning across a broad class of materials, which is of paramount importance to metallurgical technology

One-dimensional (1D) van der Waals (vdW) nanowires, formed from molecular chains bonded through weak interactions, represent a significant departure from traditional nanowires by offering the potential to miniaturize functional devices to the molecular scale while maintaining crystallinity, a feature attributable to their exfoliable nature and chemically inert surfaces. However, the lack of efficient synthesis methods has hindered the exploration of their intrinsic properties and potential applications. The production of vdW nanowires has predominantly relied on the exfoliation of bulk crystals, leaving their direct synthesis largely unexplored. In this work, we introduce a novel solid-state growth technique that facilitates the high-yield and scalable fabrication of single-crystal Ta2Ni3Se8 (TNS) nanowires, achieving a consistent thickness of 100 nm and lengths extending to several millimeters. We further demonstrate a few centimeter scale alignments of as-grown nanowires and show that these nanowires can be easily dry exfoliated to produce several nanometer-thick, air-stable nanowires. Employing density functional theory, we investigate the bonding characteristics within these nanowires, identifying a highly anisotropic bonding density that significantly contributes to their facile exfoliation. Moreover, the development of Schottky device arrays on individual TNS nanowires and subsequent electrical transport measurements affirm the uniform Schottky contact properties along their entire length, characterized by a barrier height of approximately 0.39 eV. The successful synthesis of structurally and electronically uniform, ultralong TNS nanowires may open a new avenue in developing integrated molecular electronics and sensors using 1D vdW materials.

Quasi-one-dimensional (quasi-1D) semiconductor materials from the M2N3X8 family (M = Ta, Nb; N = Ni, Pd, Pt; X = S, Se) emerge as candidates for advanced nanoelectronic applications. Unlike the well-studied metallic phases in 2D transition metal dichalcogenides (TMDs), such phases have not yet been observed in quasi-1D systems. Here, we predict the structure, properties, and stability of new metallic Ta2Pd3Se8 (TPS) polymorphs using first-principles calculations. We found two previously undetected metallic phases, 1T ' and 1T '', which are distinct from the semiconducting 1R structure. Phase transition analysis shows that partial transformation of TPS nanowires can induce metallic properties, offering an efficient way to tune conductivity. The present results place TPS nanowires as high-potential materials for memristors and neuromorphic computing that extend the frontier of quasi-1D materials in nanoelectronics.

As an emerging research field, reconfigurable electronic and optoelectronic devices based on semiconducting van der Waals (vdW) heterostructures provide distinct advantages in dimension scaling, power consumption, multiple functionalities, and tunability, making it highly suitable for applications in integrated circuits, sensors, and intelligent system. In this work, a high‐performance reconfigurable photodiode based on a hybrid‐dimensional vdW heterostructure consisting of 2D WSe 2 and 1D Ta 2 Pd 3 Se 8 is proposed. Through gate control, the semiconducting junction is switched between p‐n and n‐n configurations, resulting in a switchable rectification behavior and highly tunable self‐powered photoresponse. Under visible light excitation, the device shows good responsivity reaching 6.01 A W −1 and high external quantum efficiency (EQE) up to 1360%. Additionally, the 1D Ta 2 Pd 3 Se 8 nanowire introduces highly anisotropic crystal structure to the junction, enabling selective detection of linearly polarized light in the visible and near infrared range. This study demonstrates potential applications of reconfigurable hybrid‐dimensional vdW heterostructures in future electronic and optoelectronic devices.

One-dimensional (1D) ternary transition metal chalcogenides (M2X3Y8) have emerged as a promising class of materials for advanced electronic and optoelectronic applications. This Mini-Review comprehensively explores recent advancements in their synthesis, characterization, and integration into functional devices. The studied nanowires display exceptional performance as semiconductor 1D nanostructures in photodetection, field-effect transistors, and gas sensing. Their unique 1D structure, tunable electronic properties, and high stability make them attractive candidates for future research and development in the field of materials science.

This study investigates altermagnetic effects in nanometer-thick GdAlSi films inherited from their bulk counterpart. This altermagnetic phenomenon is characterized by momentum-dependent spin splitting in collinear antiferromagnets, governed by specific symmetry. Using ab initio calculations, we analyze the magnetic and electronic properties of GdAlSi films with various thicknesses and surface terminations. We show that while non-relativistic spin splitting at high-symmetry points in the 2D Brillouin zone is evident in thicker films, it diminishes in ultra-thin films due to surface-induced symmetry breaking. Additionally, we demonstrate that carrier concentrations in monolayer GdAlSi films are higher than in the bulk, suggesting distinct electronic transport capabilities. These findings expand the altermagnetic materials landscape towards the nanometer-size limit essential for advanced spintronic applications.

The RE6Fe13Ga phase (RE, Rare Earth) exhibits tremendous promise for achieving high-performance magnets. However, the challenge of controlling its formation and distribution hinders improvements in coercivity and squareness of Ga-doped magnets. In this study, we present a strategy to regulate the chemical composition of the RE-rich phase (0-9 at.% Cu, without Ga) and subsequently modify the phase transformation pathways of the RE6Fe13Ga phase in Ga-doped magnets by incorporating a Pr-rich Ga-Cu-containing aiding alloy. Remarkable magnetic performance was achieved, with values of Br=13.36 kGs, mu 0Hcj=20.82 kOe, (BH)max=43.75 MGOe, and mu 0Hk90/mu 0Hcj=0.99. Through quantitative analysis of chemical and structural properties and phase fractions at grain boundary (GB) triple junctions, we elucidate the phase transformation pathways in the magnets. The reaction between amorphous RE-Ga-rich phases and the matrix phases, along with partial consumption of the RErich phases with the Mn2O3-type structure (space group Ia3), led to the formation of the RE6Fe13Ga phase, accompanied by the presence of an amorphous Fe-rich transitional phase sharing a similar chemical composition. The gradual and partial involvement of the RE-rich phase improved the melt's wettability and delayed the formation of the RE6Fe13Ga phase. Consequently, a uniform microstructure was achieved, establishing the conditions for high magnetic performance. Thin metallic GBs and thick RE-rich, amorphous Fe-rich, and RE6Fe13Ga GBs were formed in the magnet. The former ensured squareness, while the sufficient coverage of the latter contributed to exceptional coercivity. The Pr-rich aiding alloy induces chemical heterogeneity, reinforcing the magnetic properties. This study advances our understanding of phase transformation pathways in Ga-doped magnets and introduces an effective approach for achieving high-performance magnets.

Van der Waals (vdWs) heterostructures based on low dimensional semiconducting materials offer tremendous opportunities in investigating next generation electronic and optoelectronic devices. Careful design based on combinations of different crystal structures and their band alignment engineering in such architectures are crucial for realizing specialized functionality and preferable performance. Here, a polarized light sensitive photodetector with high efficiency and ultrafast response speed based on hybrid dimensional MoS 2 /Ta 2 Pd 3 Se 8 vdWs heterostructure, which is owing to the unilateral depletion region as formed between the n–n junction, is reported. In particular, under ultraviolet light irradiation, the device exhibits a high external quantum efficiency of 970%, and the device shows an ultrafast response speed of 1.3 µs under visible light excitation. Moreover, the 1D Ta 2 Pd 3 Se 8 crystal introduces a highly anisotropic feature of the heterostructure, so as to realize selective detection to linear polarized light with an anisotropic ratio up to 0.66. This work sheds light on the potential applications of hybrid dimensional vdWs heterostructures, which may provide new insight for exploring high performance photodetectors with advanced functions.

We report the investigation of the microstructure and magnetic properties of a sintered (Nd,Pr)30.3-xCexFebalM1.4B0.92 (in wt.%, xCe = 0) magnet with varying Ce substitutions (xCe = 2, 4, 6, 8). Structure analysis revealed a lattice contraction with Ce addition of up to xCe < 6, and the further increase in the Ce content to 6 wt.% led to a suppression in lattice contraction. The magnetic properties showed a notable deviation from the linear trend in coercivity and remanent magnetization for the magnets with Ce content of xCe > 4. The detailed microstructure analysis revealed that the magnets with xCe > 4 exhibit the REFe2 phase at the expense of a reduced mass fraction of a REOx phase, suggesting that the generation of the REFe2 phase suppressed the formation of the REOx phase. The site occupancy and valence state of Ce, analyzed using atomic-resolution energy dispersive spectroscopy and electron energy loss spectrometry, established that the suppressed lattice contraction is accompanied by a preferential site occupation of Ce from a random case to a 4f-centric site, along with a valence change from a mixed state to a trivalent state, inferring that Ce3+ ions are rejected from the 4g site of the RE2Fe14B phase to occupy the 4f site with a subsequently reduced number of Ce4+ ions due to the magneto-volume and chemical bonding effects. These findings display a new phase formation pathway of the REFe2 phase from a valence state perspective, i.e., the part of Ce4+ ions is considered to be rejected from the RE2Fe14B phase to nucleate the REFe2 phase, which is later found to separate chemically into RE-rich and Fe-rich regions. Further, a bi-layer interfacial structure, composed of Fe-rich and RE-rich layers, is formed in between the RE2Fe14B and the REFe2 phases due to the weak wettability of the REFe2 phase and a slightly positive mixing enthalpy between Ce and Fe. The deviation in magnetic properties is discussed based on the structural and microstructural results. These findings provide structural insight for developing low-cost and high-performance Ce-substituted Nd-Fe-B magnets.

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.

In this work, the interaction of a mixture of Al and BN nanopowder with hydrogen microwave plasma was studied. Using X-ray diffraction analysis, scanning and transmission electron microscopy, the formation of AlN and AlB2 nanocrystals as a result of short-term (~ 30 ms) interaction of Al vapor with h-BN was established. Obtained results also indicate the formation of hydrogenated hexagonal boron nitride h-BN-H. The critical shear stresses were calculated for the interfaces between BN and Al, AlB2, and AlN. Approaches for increasing the strength of the composite materials based on hexagonal boron nitride and aluminum are discussed.

Experimental and theoretical investigation of new Al/SiC heteroparticles has been carried out. It is predicted that due to the appearance of a strong interface between Al and SiC, a composite material based on A; and SiC must have a significantly higher tensile strength than pure Al. Theoretical predictions are confirmed in the experiment. In particular, it is shown that the introduction of nano-SiC in a concentration of 10 wt.% in the aluminum matrix leads to an increase in the strength limit of the composite at room temperature to 317 MPa.

Using the density functional theory, we systemically investigate the structural and electronic properties of SnP3 monolayer and bilayer adsorbed on metallic substrates, including graphene (Gr), Cu(111), and Ni(111). Our main findings indicate that the SnP3 layers develop a stack with graphene through the van der Waals interaction, in contrast to strongly chemical binding, observed with the transition metals, such as Cu(111) and Ni(111). Upon building Gr/SnP3 heterostructures, we found that the Dirac cone in graphene is well preserved, forming an n-type Schottky contact with a small Schottky Barrier Height (SBH), which in turn is very sensitive to the external conditions. By reducing the interfacial distance between Gr and SnP3 layers, a Schottky contact to a p-type ohmic contact transition can be effectively realized, while an n-type ohmic contact can be generated by applying a finite external electrical field. By contrast, strong interaction with Ni(111) and Cu(111) seriously disrupts the electronic structure of SnP3 layers, that can be avoided by introducing graphene or h-BN as buffer layers between SnP3 layers and transition metal substrates. Furthermore, increasing the layer number of the inserted Gr or BN, up to bilayers, is found to be enough to achieve an n-type ohmic contact. These findings provide useful insights for designing novel SnP3-based field effect transistors (FETs) devices with n- or p-type ohmic contacts.

Micromechanical exfoliation of two-dimensional (2D) van der Waals materials has triggered an explosive interest in 2D material research. The extension of this idea to 1D van der Waals materials, possibly opening a new arena for 1D material research, has not yet been realized. In this paper, we demonstrate that 1D nanowire with sizes as small as six molecular ribbons, can be readily achieved in the Ta2(Pd or Pt)3Se8 system by simple micromechanical exfoliation. Exfoliated Ta2Pd3Se8 nanowires are n-type semiconductors, whereas isostructural Ta2Pt3Se8 nanowires are p-type semiconductors. Both types of nanowires show excellent electrical switching performance as the channel material for a field-effect transistor. Low-temperature transport measurement reveals a defect level inherent to Ta2Pd3Se8 nanowires, which enables the observed electrical switching behavior at high temperature (above 140 K). A functional logic gate consisting of both n-type Ta2Pd3Se8 and p-type Ta2Pt3Se8 field-effect transistors has also been successfully achieved. By taking advantage of the high crystal quality derived from the parent van der Waals bulk compound, our findings about the exfoliated Ta2(Pd or Pt)3Se8 nanowires demonstrate a new pathway to access single-crystal 1D nanostructures for the study of their fundamental properties and the exploration of their applications in electronics, optoelectronics, and energy harvesting.

Direct growth of graphene on insulators is expected to yield significant improvements in performance of graphene-based electronic and spintronic devices. In this study, we successfully reveal the atomic arrangement and electronic properties of a coherent heterostructure of single-layer graphene and α-Al2O3(0001). The analysis of the atomic arrangement of single-layer graphene on α-Al2O3(0001) revealed an apparentcontradiction. The in-plane analysis shows that single-layer graphene grows not in a single-crystalline epitaxial manner, but rather in polycrystalline form, with two strongly pronounced preferred orientations. This suggests relatively weak interfacial interactions are operative. However, we demonstrate that unusually strong physical interactions between graphene and α-Al2O3(0001) exist, as evidenced by the small separation between the graphene and the α-Al2O3(0001) surface. The interfacial interaction is shown to be dominated by the electrostatic forces involved in the graphene π-system and the unsaturated electrons of the topmost O layer of α-Al2O3(0001), rather than the van der Waals interactions. Such features causes graphene hole doping and enable the graphene to slide on the α-Al2O3(0001) surface with only a small energy barrier despite the strong interfacial interactions.

The review concerns graphene-based nanostructures including graphene nanoribbons a few nanometres wide, structures functionalized with hydrogen and fluorine atoms as well as pure carbon composites. The physicochemical properties and the chemical engineering methods for their fabrication are considered. Methods for solving problems in modern nanotechnology are discussed. Possible applications of graphene and graphene-based nanostructures in various devices are outlined. The bibliography includes 286 references.