Binary chromium carbides display excellent wear resistance, extreme stiffness and oxidation resistance under high temperature. The influence of applied pressure on electronic structure, elastic behavior, Debye temperature and hardness of Cr₇C₃, Cr₃C₂ and Cr₂₃C₆ have been investigated by the density functional theory (DFT) method. The results reveal that lattice parameters and formation enthalpy display an inverse relationship with applied pressure, and Cr₃C₂ exhibited optimal structural stability. Moreover, Cr-C orbital hybridization tends to be stronger due to the decreased partial density of states (PDOS) of the Cr atom. The difference in electronic distribution of binary carbides has also been investigated, which confirmed that overall orbital hybridization and covalent characteristics has been enhanced. The theoretical hardness was elevated according to the higher bond strength and bond density. In accordance with structural stability data, Cr₃C₂ has shown maximum theoretical hardness. Furthermore, the anisotropic nature of hardness has been evaluated with external pressure. Cr₃C₂, and the highest isotropic hardness behavior along with an increase in hardness values with increasing pressure has been observed. In addition, the variation in Debye temperatures of binary chromium carbides under applied pressure has also been predicted. The results provide a theoretical insight into electronic, mechanical and thermodynamic behavior of three binary chromium carbides and show the potential of these novel carbides in a wide range of applications.

The resistance drift phenomenon observed in amorphous chalcogenide phase-change materials (PCMs) hinders the development of PCM-based neuro-inspired computing devices. It has been observed that the drift in electrical resistance can be effectively reduced by substituting Ge with Sn in the prototype PCM GeTe, forming amorphous (Ge_1−xSn_x)Te solids. However, the atomistic and chemical origin of such drift suppression phenomenon remains unclear. In this work, we carry out thorough ab initio simulations and chemical bonding analyses of amorphous Ge–Sn–Te materials. We show that the two critical driving forces for glass relaxation in PCMs, i.e. the amount of tetrahedral motifs and the degree of Peierls distortion, are gradually reduced as Sn content increases. Such trend can be explained by the increased ionicity brought about by the Ge → Sn substitution. Our work suggests that an optimal Sn-rich GeSnTe composition could be reached for PCM-based neuro-inspired computing with ultralow resistance drift.

Kirigami‐ and oirigami‐inspired techniques have emerged as effective strategies for material structure design; however, the use of these techniques is usually limited to soft and deformable materials. Piezoelectric ceramics, which are typical functional ceramics, are widely used in electronic and energy devices; however, the processing options for piezoelectric ceramics are limited by their brittleness and feedstock viscosity. Here, a design strategy is proposed for the preparation of lead‐free piezoelectric ceramics inspired by kirigami/origami. This strategy involves direct writing printing and control over the external gravity during the calcination process for the preparation of curved and porous piezoelectric ceramics with specific shapes. The sintered BaTiO₃ ceramics with curved geometries produced using this strategy exhibit a high piezoelectric constant (d₃₃ = 275 pC N⁻¹), which is 45% higher than that of conventionally sintered sheet ceramics. The curved structure of the ceramics is well‐suited for use in the human body and it was determined that these curved ceramics can detect pulse signals. This strategy can be applied in the large‐scale and low‐cost production of other piezoelectric ceramics with various curved shapes and provides a new approach for the preparation of complex‐shaped ceramics.

A profound overview of the recent development for on-time, on-demand hydrogen production from light metal-based hydrolysis is presented. Hydrogen energy is one of the clean and renewable energy sources which has been recognized as an alternative to fossil fuels. In addition, aluminum is the most suitable light activity metal for hydrolysis materials attributed to its safety, environmental friendliness, high-energy density, inexpensive, and low density with high strength ratio. In general, dense oxide films formed act as a barrier on aluminum surfaces. Accordingly, effective removal of the oxide film is a key measure in solving the Al–water reaction. In this review, recent advances in addressing the main drawbacks including high-purity aluminum with acid–alkali solutions, nano-powders of aluminum or composite with acid–base solutions, ball-milled nano-powders, alloying blocks, and gas atomization powders are summarized. The characteristics of these three technologies and the current research progress are summarized in depth. Moreover, it is essential to promote low-cost aluminum-based materials based on effective hydrogen production efficiency and explore ways for practical large-scale applications.

In this study, a Cr₃C₂-NiCr cermet cladding layer was prepared on the surface of Q235 steel via a high-speed laser cladding method. The effects of laser power, scanning speed, and overlap rate on the microstructure, cladding quality, and interfacial elements diffusion of Cr₃C₂-NiCr/Q235 steel were studied. The results show that there was an obvious transition layer at the interface of the Cr₃C₂-NiCr cladding layer and Q235 steel, indicating that the Cr₃C₂-NiCr cladding layer had an adequate metallurgical bond with the matrix. Fe, Cr, and Ni were diffused distinctly between the cladding layer and the matrix. The height and width of the Cr₃C₂-NiCr cladding layer increased, while the dilution rate decreased with the increase in the laser power. The maximum thickness of the transition layer was about 50 μm for the 6 mm/s sample, the weld heat affected zone was smaller, and it was shown that the productivity can be effectively improved. The sample with a 40% overlap rate exhibited the best flatness. The optimal laser power, scanning speed, and overlap rate of the Cr₃C₂-NiCr/Q235 steel were 1500 W, 6 mm/s, and 40%, respectively.