Transition metal dichalcogenides (TMDCs) have emerged as promising materials for electromagnetic interference (EMI) shielding; however, the interfacial mechanisms governing their shielding performance remain poorly understood. Herein, atomic layer deposition (ALD) was employed to precisely regulate the thickness, density, and morphology of semiconducting (MoS2, WS2) and metallic (TaS2, NbS2) TMDCs nanofilms on carbon cloth(CC), enabling the controlled construction of TMDCs/CC heterointerfaces for systematic comparison. The TMDCs/CC samples exhibit excellent EMI shielding behavior at a total thickness of only 0.3 mm. In particular, NbS2@CC achieves the highest SET (58.4 dB) and the highest SE/t (194.7 dB mm(-1)), despite having the lowest conductivity (545 S cm(-1)). Counterintuitively, TaS2 with the highest conductivity (610 S cm(-1)), delivers the lowest SET (50.8 dB). Combined electromagnetic analyses and density functional theory (DFT) calculations reveal that EMI shielding performance is governed predominantly by interfacial polarization at the TMDCs/CC interface, rather than by bulk conductivity or electronic polarity. This interfacial polarization is driven by the Fermi-level difference (Delta EF), which regulates charge transfer and electromagnetic energy dissipation across the heterointerface. Importantly, the interfacial Delta EF is identified as a quantitative descriptor for predicting EMI shielding performance in TMDCs systems.

Based on first-principles density functional theory (DFT) calculations, heterostructures composed of graphene and two-dimensional semiconducting materials exhibit significant potential for applications in nanoelectronics devices. In this study, we propose an innovative approach to modulate the electronic properties of such heterostructures. We conduct a comprehensive investigation into the structural properties, band structures, and band alignments of ten widely studied two-dimensional semiconducting materials, unveiling opportunities for forming Schottky contacts with graphene. Furthermore, we demonstrate that the work function of graphene can be extensively tuned via boron or nitrogen doping. Our findings reveal that B- or N-doping in graphene substantially modifies the electronic properties of graphene/two-dimensional semiconducting materials heterostructures, enabling transitions between p-type and n-type Schottky contacts and even facilitating a shift from Schottky to Ohmic contacts in some cases. This tunability is critical for the precise design of graphene/two-dimensional semiconducting materials heterostructures with optimized Schottky barrier heights, paving the way for advanced nanoelectronics and catalyst applications.

Pristine two-dimensional (2D) GaN is non-magnetic, which limits its direct use in semiconductor spintronics. Here, first-principles calculations were used to screen 3d transition-metal substitution (TM = Sc-Zn) at 6.25 at.% and 9.375 at.% and to evaluate biaxial strain from \(-3%\) to \(3%\). Co substitution produced the most favorable magnetic semiconductor response among the screened dopants. The two concentrations yielded magnetic moments of \(8.00\) and \(12.00\) \(\mu_B\) per supercell and band gaps of \(0.80\) and \(0.55\) eV, respectively. Biaxial strain preserved the magnetic order while tuning the band gaps. In the \(6.25\) at.% Co-doped system, the gap reached \(0.89\) eV at \(2%\) tensile strain and became direct at \(3%\) tensile strain. These calculations identify Co substitution and moderate biaxial strain as a promising theoretical route for tuning the magnetic and electronic properties of monolayer GaN.

Density functional theory is used in this work to examine the photoelectric properties of the Hf2CO2/WSSe and the Zr2CO2/WSSe. The calculation results show that these heterojunctions have significant peaks of absorption in the visible region compared with intrinsic materials, indicating that they can effectively capture visible light. Furthermore, the change of Gibbs free energy tends to zero, which is beneficial to the spontaneous reaction of electrocatalytic water splitting to produce H2. Interestingly, by calculating photocurrent, we found that the maximum photocurrent of the Hf2CO2/WSSe reached 14.09 a 0 2 /photon, and that of the Zr2CO2/WSSe up to 47.02 a 0 2 /photon, which showed extremely high photoelectric response sensitivity, making Hf2CO2/WSSe and the Zr2CO2/WSSe can be used to design high-performance photodetector.

The broken mirror symmetry in Janus SMoSe and SWSe monolayers induces novel properties for photocatalytic, thermoelectric and photocatalytic devices. Interlayer coupling is critical in van der Waals (vdW) heterostructure for quantum transport and polaritonics. We investigate Janus SMoSe/SWSe vdW heterostructures with three stacking interfaces: S-S, S-Se, and Se-Se. The S-Se SMoSe/SWSe vdW heterostructure with lowest symmetry exhibits ultralow frequencies of in-plane shear (1.94 cm- 1) and out-of-plane breathing (4.47 cm- 1) modes due to weaker interlayer vdW restoring forces and a significant intrinsic vertical dipole moment. The reduced restoring forces are caused by the critical charge transfer across the vdW interface. Thus, the larger interlayer spacing in the S-Se SMoSe/SWSe heterostructure results in the suppressed vdW interlayer coupling for ultralow phonon frequencies. These findings advance understanding of tuning vdW coupling in polar Janus SMoSe/SWSe heterostructures by stacking engineering, providing theoretical insights for designing tunable nanoelectronic devices.

Janus two-dimensional materials including transition metal dichalcogenides, transition metal carbides and carbonitrides, and metal-organic frameworks, exhibit unique electronic, optical, piezoelectric, and dielectric properties due to their asymmetric atomic structures, making them promising candidates for nanoelectronics, energy storage conversion and storage, and biomedical applications. This review comprehensively highlights the unique properties and typical applications of Janus two-dimensional materials and their van der Waals heterostructures. We explore the fundamental mechanisms underlying their electronic and optoelectronic properties, including band structures and light absorption. Strategies for enhancing their performance are discussed, providing a framework for addressing future research challenges. This comprehensive review integrates theoretical insights, synthesis techniques, and diverse applications, emphasizing the potential of Janus twodimensional materials to revolutionize hydrogen production and other technological domains. We conclude by summarizing current advancements and future directions, offering inspiration for continued innovation in two-dimensional materials applications.

Designing high-performance negative electrode materials is crucial for the development of sodium-ion batteries (SIBs). In this article, B-doped graphene and blue phosphorous (B-G/BP) heterostructure as an anode material for SIBs was studied using density functional theory (DFT) calculations. Compared with graphene and blue phosphorus (G/BP) heterostructures, the B-G/BP heterostructure exhibits significantly enhanced adsorption capacity for Na. This result suggests that the B-G/BP heterostructure can better prevent the formation of Na metal clusters. Charge distribution analysis shows that electrons can transfer from B atom to adjacent C atoms (about-1.89 e). The electron deficient nature of the B-G/BP heterostructure makes its strong adsorption of Na. From the analysis of density of states, the doping of B is actually equivalent to P-type doping of graphene, enhancing the conductivity of B-G/BP heterostructure. Moreover, the Na diffusion barrier of B-G/BP heterostructure is 0.27 V. For B-G/BP heterostructure, the average open-circuit voltage (OCV) is 0.77 V and the theoretical capacity of interlayer adsorption of Na is 142.47 mAh/g. These insights demonstrates that the B-G/BP heterostructure can become an ideal anode material for SIBs.

In this work, the stability and migration behavior of He in Ti doped β-TMH 2 (TM = Sc and Er) are investigated by using density functional theory (DFT) calculations.

Density functional theory is used in this work to examine the photoelectric properties of the Hf2CO2/WSSe and the Zr2CO2/WSSe. The calculation results show that these heterojunctions have significant peaks of absorption in the visible region compared with intrinsic materials, indicating that they can effectively capture visible light. Furthermore, the change of Gibbs free energy tends to zero, which is beneficial to the spontaneous reaction of electrocatalytic water splitting to produce H2. Interestingly, by calculating photocurrent, we found that the maximum photocurrent of the Hf2CO2/WSSe reached 14.09 a02 /photon, and that of the Zr2CO2/WSSe up to 47.02 a02 /photon, which showed extremely high photoelectric response sensitivity, making Hf2CO2/WSSe and the Zr2CO2/WSSe can be used to design high-performance photodetector.

Cu–Al alloys are widely used in electronics, new energy, and other fields due to the combination of th excellent corrosion resistance and electrical conductivity of Cu and the light weight of Al. In this paper, the powder metallurgy and equal-channel angular pressing compound technology was used to fabricate a Cu–Al alloy joint, which can be used to replace armor. Devices such as an optical microscope, electron scanning microscope, and microhardness scale were used to characterize the microstructure and mechanical properties of the Cu–Al alloys. The finite element analysis software Abaqus was used to analyze stress distribution during equal-channel angular pressing. The results indicated that the microstructure and properties of Cu–Al alloys were closely related to the volume ratio of Cu–Al. The microhardness and tensile strength were significantly increased by increasing the volume ratio of Cu–Al. As the volume ratio of Cu–Al varied from 1:2 to 2:1, the ultimate tensile strength of the Cu–Al alloys increased from 79.9 MPa to 164.9 MPa at room temperature and the microhardness increased from 60 HV to 101 HV. However, the elongation of the Cu–Al alloys hardly changed; this was about 4.4%. Crack initiation occurred at the Cu–Al interface and spread along the bonding surface of the Cu–Al alloys during the tensile process.

In this paper, a piezoelectric atomizing nozzle applied to photoresist coating is designed. The structure of its vibration system is designed according to the application scenario. The liquid supply channel is designed in the central axis of the vibration system, and the front cover plate of the piezoelectric transducer and the amplitude transformer are integrated. The modal simulation analysis is carried out by COMSOL to verify the rationality of the design of the vibration system of the piezoelectric atomizer. The photoresist was atomized by a designed piezoelectric atomizer nozzle, and the particle size of atomized droplets was measured and analyzed. It was found that the atomized droplets had uniform distribution and small particle size, which was conducive to improving the coating quality of photoresist.

In this paper, we propose a series of novel one-dimensional group V semiconductors with a square columnar structure, denoted as SC-As, SC-Sb, and SC-Bi, derived from SC-P. Phonon dispersion calculations reveal their dynamic stability, while first-principles calculations show versatilities in their electronic and optical properties influenced by spin–orbit coupling. SC-P, SC-As, and SC-Sb exhibit strong sunlight absorption with intensities exceeding 3 × 105 cm−1, while SC-Bi demonstrates exceptional absorption spanning the entire solar flux spectrum. Furthermore, band alignment denotes that the SC-P is suitable for photocatalytic water splitting in both acidic and alkaline environments, while SC-As and SC-Sb work in alkaline conditions. These findings unveil the potential of these materials in solar energy harvesting and photocatalytic hydrogen production, advancing the development of group V 1D semiconductors.

Helium (He) in rare-earth metal hydrogen storage materials tends to aggregate and produce bubbles and release them, which has an impact on the lifetime of the materials. Therefore, it is crucial to study the aggregation behavior of He to improve the lifetime of the materials. In this paper, two forms of interstitial doping and substitution doping are selected by density-functional theory (DFT) calculations, and the effects of Al doping in ScH2 on the geometries, formation energies, and binding energies of He atoms, as well as the migration behaviors of the doped Al atoms on the migration of the He atoms are investigated in detail. Finally, it is demonstrated that Al doping in ScH2 makes it difficult for He atoms to exist near and stabilize the vacancies close to Al atoms, which is likely to inhibit the formation of clusters of He, and provides a strong basis for the realization of the improvement of helium-solidifying properties of ScH2 materials.

The present study explores the structural, phase stability, mechanical, and electrical properties of Mg-Ho intermetallic phases, namely Mg24Ho5, Mg2Ho, and MgHo. The investigation is conducted using the first-principles plane-wave pseudopotential method within the framework of density functional theory, as implemented in the Vienna Ab initio Simulation Package. The primary objective of this research is to illuminate the phase stability and mechanical behavior of these compounds, which are of paramount importance for their potential applications in magnesium alloys. The study determines the formation enthalpy (Delta H) and elastic constants (C-ij) for each intermetallic phase and calculates the elastic moduli of the corresponding polycrystalline materials. The findings of this study reveal that the MgHo phase exhibits the highest absolute value of formation enthalpy (Delta H = -8.01 kJmol(-1)), indicating its superior stability among the three investigated intermetallic phases. As the concentration of Ho in Mg increases, the G/B ratio for the phases decreases from 1.02 to 0.60 (>0.57), suggesting that the intermetallic phases are stable, albeit brittle. The elastic anisotropy index (A(U)), derived from the elastic constants (C-ij), follows an ascending order of Mg24Ho5, Mg2Ho, and MgHo, signifying that MgHo possesses the most favorable elastic anisotropy among the studied phases.

The densification of a SiCp/Al–Fe–V–Si billet was achieved by reducing the pores and oxide film between the particles by rolling. The wedge pressing method was used to improve the formability of the composite after jet deposition. The key parameters, mechanisms, and laws of wedge compaction were studied. The results showed that the pass rate was reduced by 10 to 15 percent when using steel molds during the wedge pressing process if the distance between the two ends of the billet was about 10 mm, which was beneficial to improve the compactness and formability of the billet. The density and stress of the surface of the material were higher than those of the interior, where the distribution of density and stress tended to be uniform as the overall volume of the material shrank. During the wedge extrusion process, the material in the preforming area was thinned along the thickness direction, while the material in the main deformation area was lengthened along the length direction. Under plane strain conditions, the wedge formation of spray-deposited composites follows the plastic deformation mechanism of porous metals. The true relative density of the sheet was higher than the calculated value during the initial stamping phase, but was lower than the calculated value when the true strain exceeded 0.55. This was due to the accumulation and fragmentation of SiC particles, which made the pores difficult to remove.

Spintronic devices play a pivotal role in contemporary industrial technology. This study employs first-principles calculations to scrutinize the geometric structure, binding energy, formation energy, electronic properties, and magnetic behavior of 3d transition metal (TM) atoms-doped monolayer GaN. Our investigation reveals the robustness of TM-substituted GaN systems, with magnetic states observed for Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, excluding Sc. Notably, Ti, Cr, Fe, and Co substitutions result in spin-polarized semiconductor behavior, while Mn, Ni, and Zn doping induces a half-metallic state, and V doping yields metallic characteristics. These findings underscore the magnetic potential of GaN monolayers upon dopant incorporation, indicating promising prospects for spintronic applications.

Hydrogen production through photocatalytic water splitting is being developed swiftly to address the ongoing energy crisis. Over the past decade, with the rise of graphene and other two-dimensional (2D) materials, an increasing number of computational and experimental studies have focused on relevant van der Waals (vdW) semiconductor heterostructures for photocatalytic water splitting. In this review, the fundamental mechanism and distinctive performance of type-II and Z-scheme vdW heterostructure photocatalysts are presented. Accordingly, we have conducted a systematic review of recent studies focusing on candidates for photocatalysts, specifically vdW heterostructures involving 2D transition metal disulfides (TMDs), 2D Janus TMDs, and phosphorenes. The photocatalytic performance of these heterostructures and their suitability in theoretical scenarios are discussed based on their electronic and optoelectronic properties, particularly in terms of band structures, photoexcited carrier dynamics, and light absorption. In addition, various approaches for tuning the performance of these potential photocatalysts are illustrated. This strategic framework for constructing and modulating 2D heterostructure photocatalysts is expected to provide inspiration for addressing possible challenges in future studies.

A low-temperature liquid phase sintering method combined with post heat treatment was employed to prepare p-type Bi 0.5 Sb 1.5 Te 3 /SiC composites with enhanced thermoelectric properties.

Protein hydrogels have attracted increasing attention because of their excellent biodegradability and biocompatibility, but frequently suffer from the single structures and functions. As a combination of luminescent materials and biomaterials, multifunctional protein luminescent hydrogels can exhibit wider applications in various fields. Herein, we report a novel, multicolor tunable, injectable, and biodegradable protein-based lanthanide luminescent hydrogel. In this work, urea was utilized to denature BSA to expose disulfide bonds, and tris(2-carboxyethyl)phosphine (TCEP) was employed to break the disulfide bonds in BSA to generate free thiols. A part of free thiols in BSA rearranged into disulfide bonds to form a crosslinked network. In addition, lanthanide complexes (Ln(4-VDPA)3), containing multiple active reaction sites, could react with the remaining thiols in BSA to form the second crosslinked network. The whole process avoids the use of nonenvironmentally friendly photoinitiators and free radical initiators. The rheological properties and structure of hydrogels were investigated, and the luminescent performances of hydrogels were studied in detail. Finally, the injectability and biodegradability of hydrogels were verified. This work will provide a feasible strategy for the design and fabrication of multifunctional protein luminescent hydrogels, which may have further applications in biomedicine, optoelectronics, and information technology.

A definitive understanding of the addition of Si on the mechanism of intergranular corrosion (IGC) in Al–Mn–Fe–Mg–Cu alloy is still unclear. The microstructure at the grain boundaries in Al–Mn–Fe–Mg–Cu alloy were characterized by high resolution transmission electron microscopy (HRTEM). The Si layer and discrete Al4Cu2Mg8Si7 and α-Al(Fe,Mn)Si precipitates along the grain boundary, and precipitation-free zone (PFZ) adjacent to the grain boundary contribute to IGC.