Robust Pristine MXene Films with Superhigh Electromagnetic Interference Shielding Effectiveness via Spatially Confined Evaporation

Abstract

Lightweight, thin electromagnetic interference (EMI) shielding film materials with high shielding effectiveness and good mechanical performance are highly required for flexible and portable electronics. Two-dimensional titanium carbide (Ti 3 C 2 T x MXene) has a great potential to meet these requirements because of the easy fabrication of ultrathin conductive films via solution processing. However, the production of strong pristine MXene films is still challenged by the presence of voids and wrinkles, as well as inferior flake alignment. In this work, high-performance pristine MXene films are produced by a spatially confined evaporation approach with controlled wet film thickness. When the cast dispersion layer is sufficiently thin, the skin effect is suppressed during evaporation, producing films with improved flake alignment and much fewer structural defects. As a result, the pristine MXene films deliver an ultrahigh tensile strength of 707 MPa and a high modulus of 66 GPa, together with a high electrical conductivity of 16600 S cm −1 . The high conductivity and intrinsic laminated structure endow the MXene films with superior EMI shielding performance in X-band (48.4 dB and 1.3 × 10 5 dB cm −2 g −1 for 1.0 μm thick films), being among the highest values reported.

Bilayered Distribution of Ag and Fe3O4 in Electrospun TPU Films for Low-Reflection Electromagnetic Interference Shielding and Multiple Thermal Management Functionalities

“…Generally, the EMI shielding performance of materials depends largely on their conductivity. The higher the conductivity, the higher the electromagnetic interference shielding effectiveness (EMI SE) Figure a,b shows the electrical conductivity of all the TPAF composite films.…”

“…The higher the conductivity, the higher the electromagnetic interference shielding effectiveness (EMI SE). 46 conductivity of TPAF composite films increases from 8.36 × 10 2 to 8.62 × 10 5 S/m, which is related to the electroless plating time. In addition, one can see that the lower layer of the composite film is able to light an LED lamp, while the lower layer can not, as shown in Figure S7.…”

Porifera‐Inspired Lightweight, Thin, Wrinkle‐Resistance, and Multifunctional MXene Foam

“…[1][2][3] The emergence of transition metal carbides and/or nitrides (MXenes) has made it possible to build high-performance EMI shields by using thin films or low-density porous foams/aerogels owing to their comparable electrical conductivity to metals, large specific surface area, the ease of processing, and abundance of surface functional groups. [4][5][6][7] For instance, the thin yet robust, highly electrically conductive MXene films have been widely prepared through vacuum filtration, [8] spatially confined evaporation, [9] and various coating methods. [10] Despite the high EMI shielding effectiveness achieved for the films at low thicknesses ranging from several to hundreds of micrometers, it is inevitable to encounter the compact stacking of MXene flakes, which leads to a high density of the EMI shields.…”

Structural, Optical, and Mechanical Insights into Cellulose Nanocrystal Chiral Nematic Film Engineering by Two Assembly Techniques

“…Advanced materials with uniform architecture at multiple scales are essential for achieving exceptional mechanical properties and on-demand functionalities . Precisely controlling nanostructures with minimized defects and understanding the multiscale structure–property relationships are the fundamental of constructing high-performance functional materials. , With specific multiscale structural engineering, materials can realize an unusual combination of dissimilar properties, including mechanic–electrical, , optical, , magnetic, and other properties. − For instance, the chiral nematic structure, also known as twisted plywood and cholesteric structure, − is a typical example of hierarchical architectures with mechanical–functional combination, which are widely present in the animal and plant kingdoms.…”