大片单层低缺陷MXene的制备及其膜材料的电磁屏蔽性能

MXene is a novel two-dimensional material with good hydrophilic surface and superior metallic conductivity. However, high quality MXene with large area, single layer and low-defect is still difficult to be prepared thus far. In this paper, single layer MXene with large area and low-defect was prepared by in situ HF etching Ti₃AlC₂. The microstructures of MXene were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), atomic force microscopy(AFM) and so on. The results show that the size of MXene flakes reaches a few microns and the thickness of flakes is only 1.6 nm; no particle oxidation can be found around flakes. The MXene films were prepared by filtering MXene aqueous solution. The MXene films have the characteristics of high conductivity and outstanding toughness. The conductivity of MXene films is as high as 3280 S/cm. By testing the electromagnetic interference shielding performance of MXene films, the electromagnetic interference shielding effectiveness of the material can reach as high as 60.6 dB with 8 μm thickness and the SSE/t value is up to 19531.1 dB•cm²•g^-1. In addition, after analyzing the electromagne-tic shielding mechanism of MXene film, we know that it follows an absorption-dominant electromagnetic interference shielding mechanism.