MXene (Ti₃C₂T_x) film prepared by vacuum-assisted filtration (V-MXene film) is the most common 2D MXene macroscopic assembly with ultra-high electrical conductivity, tunable interlayer space, diverse surface chemical properties, favorable mechanical properties and so on, showing great commercial value in the fields of energy storage, electromagnetic interference shielding and actuators and so on. This paper focuses on the preparation, properties and applications of V-MXene film, objectively reviews and evaluates the important research progress of V-MXene film in recent years and analyzes the main problems at present. In addition, the development direction and trend of V-MXene film in the future are prospected from the aspects of preparation, property control and application fields, which provide guidance and inspiration for the further development of functional MXene-based films and make contributions to the progress of MXene technology.

In this paper, density functional theory calculations are adopted to systematically study the magnetic-structure anisotropy association and strain induced structure variants switching behavior of ferroelastic $1{\mathrm{T}}^{\prime }\text{−}{\mathrm{CrS}}_2$ and ${\mathrm{CrSe}}_2$. We find that the easy magnetization axis is always perpendicular to Cr-Cr zigzag chain in the ferromagnetic (FM) $1{\mathrm{T}}^{\prime }$ phase. In addition, the mechanical strain can alter the relative thermodynamic stability among the three different crystal orientation variants of both the FM and nonmagnetic (NM) $1{\mathrm{T}}^{\prime }$ phase. These two facts lay the ground for strain-controlled magnetic moment rotation of the FM $1{\mathrm{T}}^{\prime }$ phase. A prototypical design and operating mechanism of a strain-controlled $1{\mathrm{T}}^{\prime }$-FM/NM/FM heterostructure spin valve are presented. Our finding offers a potential solution to reduce energy consumption in miniaturized spintronics devices.

In this work, CdSe was taken as the representation to systematically investigate the (111) and (110) surface reconstructions, the electronic properties transition related to the layer size, and the corresponding physical mechanism through the density functional theory (DFT) calculation. For the (111) surface slab structure, the bulk truncated relaxation (BTR) surface and the honeycomb (HC) surface were carefully examined. The HC surface configuration, ignored by previous studies, is an energetically preferred surface compared to both the as-truncated and BTR configurations. Based on the HC surface, the band structure of the (111) surface shows a semiconductor character below four layers (4L). Surprisingly, the (111) CdSe turns metallic in the 4L system. In a higher-layer (>4L) system, the two side surfaces and internal regions show metallic and semiconductivity features, respectively. Such an abundant electronic properties transition should be attributed to the electron transfer under the intrinsic polarization perpendicular to the asymmetrical (111) plane. Different from the (111) surface, drastic structural reconstructions were not observed in the (110) surface and the band gap gradually decreased with the increasing number of layers until it approached the value in the bulk. Our results not only revealed the additional possible surface structure but also clarified the underlying mechanism of semiconductor-to-metal (even the edge metallic) transition related to the number of layers. All these findings could be extended to other II-VI group MX compounds for further development of electronic devices.

Lightweight and flexible porous MXene films have emerged as promising candidates for electromagnetic interference (EMI) shielding and infrared stealth. However, current foaming techniques remain a challenge in preserving the intrinsic properties of MXene while achieving eco‐friendly foaming. Herein, supercritical CO ₂ foaming technology is employed to realize the green foaming of dense MXene films without compromising the inherent structure of the MXene nanosheets. The phase transition of supercritical CO ₂ induces bubble nucleation and growth, effectively unfolding the stacked MXene nanosheets into a porous architecture. This strategy is broadly adaptable and can also be extended to other two‐dimensional (2D) films, such as graphene oxide. Benefiting from highly‐conductive porous skeleton, the foamed porous MXene film exhibits an EMI shielding effectiveness of ∼73.2 dB, which is 21% higher than that of the pristine MXene films. Furthermore, its absolute shielding effectiveness attains 23160 dB·cm ² /g, surpassing most previously reported MXene‐based porous materials. Notably, the porous MXene films also demonstrate excellent infrared thermal camouflage performance across a broad temperature window. This work not only offers an insight for the foaming of 2D MXene materials but also highlights the considerable engineering prospects of porous MXene films in the field of safety protection.