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In recent times, newly unveiled 2D materials exhibiting exceptional characteristics, such as MBenes and MXenes, have gained widespread application across diverse domains, encompassing electronic devices, catalysis, energy storage, sensors, and various others. Nonetheless, numerous technical bottlenecks persist in the development of high‐performance, structurally flexible, and adjustable electronic device materials. Research investigations have demonstrated that 2D van der Waals superlattices (vdW SLs) structures comprising materials exhibit exceptional electrical, mechanical, and optical properties. In this work, the advantages of both materials are combined and compose the vdW SLs structure of MBenes and MXenes, thus obtaining materials with excellent electronic properties. Furthermore, it integrates machine learning (ML) with first‐principles methods to forecast the electrical properties of MBene/MXene superlattice materials. Initially, various configurations of MBene/MXene superlattice materials are explored, revealing that distinct stacking methods exert significant influence on the electronic structure of MBene/MXene materials. Specifically, the BABA‐type stacking of CrB (layer A) and Co2CO2 MXene (layer B) is most stable configureation. Subsequently, multiple descriptors of the structure are constructed to predict the density of states of vdW SLs through the employment of ML techniques. The best model achieves a mean absolute error (MAE) as low as 0.147 eV. [ABSTRACT FROM AUTHOR]

Gradient nanostructured metals have become one of the research hotspots in the field of materials science due to their excellent mechanical properties and unique deformation behavior. In our contributions, the nanotwin gradient was introduced into the nanocrystalline Ni–Co alloy, and the influence of the gradient structure on the shear properties and microscopic deformation behavior was studied in order to reveal the strengthening mechanism. The gradient nanotwin Ni–Co alloy has elastic deformation and work hardening at the initial shear stage. The stress decreases after reaching the stress limit, and the uniform plastic deformation is maintained at the later stage. The excellent stability of fine twin layer and its effective hindrance to dislocation nucleation and movement can improve the strength of the material. In addition, the yield and work hardening of nanotwin gradient Ni–Co alloy are easy to occur at low temperature, and the stress–strain curve fluctuates obviously. At high temperature, the alloy is prone to plastic deformation, and the strength is reduced macroscopically. The higher the temperature is, the more difficult it is to yield. The results provide a solid theoretical basis for the design of Ni‐based alloys. [ABSTRACT FROM AUTHOR]

Due to silicon having a sp3 hybridization configuration in nature, most monolayer 2D silicon allotropes have to be proposed based on the dumbbell‐like units to ensure their structural stability. Herein, hydrogenated monolayer 2D silicon allotropes are predicted, and the sp3 configuration of structures is guaranteed by covering the surface with hydrogen. Compared with the corresponding hydrogen‐free structures and the hydrogen‐free structures on Ag(111) substrate, these predicted structures have lower formation energies, indicating that these monolayer 2D silicon allotropes can be obtained by hydrogenation reactions. These predicted structures are all dynamically stable and structures SCH, HPH, and HDH are thermodynamically stable. The structure SLH is the transition‐state structure of structure SCH and structures OTQTH and HHKH are metastable structures. The stable and metastable structures are all semiconductors and can be applied to semiconductor devices. All of these monolayer 2D silicon allotropes have high gravimetric hydrogen contents and may have applications for chemical hydrogen storage or water‐enabled H2 production. It is believed that the results of this work have a good reference value for the experimental synthesis of hydrogenated monolayer 2D silicon allotropes, and have reference significance for understanding the diversity and electronic properties of hydrogenated monolayer 2D silicon allotropes. [ABSTRACT FROM AUTHOR]

The addition of oxygen atoms in solid solution to α‐Ti alloy can increase not only its hardness but also its brittleness. Herein, the edge dislocation mobility of Ti–O single crystals at oxygen concentrations of 0–2 at% and temperatures of 100–900 K is investigated by molecular dynamics simulations. The results show that the interstitial oxygen atoms have a strong hindering effect on the a/3 [112¯0] edge dislocations on the {1¯100} prismatic planes, which is attributed to the pinning effect of the vacancy clusters on the dislocation movement due to the interstitial oxygen atoms, thus leading to pronounced dislocation strengthening and hardening. The critical resolved shear stress (CRSS) for dislocation movement increases with increasing oxygen content and decreases with increasing temperature. Moreover, the effect of oxygen concentration on dislocation mobility also diminishes with increasing temperature. [ABSTRACT FROM AUTHOR]

Herein, the effects of different Co content and temperature factors on the shear mechanical properties of nano‐polycrystalline nickel–cobalt alloy are analyzed by molecular dynamics (MD) simulations. It is found in the work that the highest shear modulus of 63.03 GPa is obtained when the Co content is 10%, attributed to the lattice distortion caused by the difference in the lattice parameters between two elements. During the shearing process, the multilevel twins are present with intensification of the deformation process, resulting in excellent dynamic shear performance. Shockley dislocations will drive the stacking faults and other partial dislocations to constitute a tetrahedral edge, and finally forms a tetrahedral structure. In addition, as the temperature of the shear environment increases, the highest strain and stress decrease. The grain boundary atoms increase significantly, and the atoms inside the grains decrease accordingly. As the degree of atomic disorder increases, the grain boundaries will melt gradually. The decrease of partial dislocation density can weaken the entanglement effect caused by dislocations. The previous conclusions promote the product development and application of nano‐polycrystalline alloys in the future, and provide important guidance significant for the engineering application of nickel–cobalt alloys. [ABSTRACT FROM AUTHOR]