High-efficiency electromagnetic interference shielding capability of magnetic Ti3C2Tx MXene/CNT composite film

Highly conductive Ti3C2Tx MXene-based electromagnetic interference (EMI) shielding materials have shown great application potential in facing the increasingly serious electromagnetic radiation threat but are limited by their single-loss mechanism. Here, to enrich the wave loss mechanism, magnetic Ti3C2Tx MXene and conductive carbon nanotubes (CNTs) have been assembled into a flexible "brick-mortar" layered NiCo/MX-CNT film to simultaneously obtain high conductivity and strong attenuation capacity. Interestingly, by combining the strong attenuation ability of the magnetic NiCo/MX and high conductivity of CNTs, as well as the dense stacking "brick-mortar" layered structure, 99.99999991% (90.7 dB of EMI shielding effectiveness, SE) of the electromagnetic waves can be reflected and absorbed by the NiCo/MX-CNT composite film with only 53 mu m thickness, which is one of the best shielding effects achieved and is superior to that of pure CNT film (similar to 71 dB) and pure MXene film (similar to 61 dB), even if they have higher conductivity. Moreover, the composite film can realize EMI shielding property modulation from 46 to 105 dB by adjusting the film thickness from 9 to 116 mu m. The dense stacking "brick-mortar" layered structure endows the composite film with excellent flexibility, foldability, and robust mechanical properties, which significantly improve the practical potential in complex application environments.