大片单层低缺陷MXene的制备及其膜材料的电磁屏蔽性能

Preparation of Large-size Single Layer MXene with Low Defect and Electromagnetic Shielding Performance of MXene Film

采用原位生成氢氟酸法刻蚀Ti3AlC2制备了单片层二维过渡金属碳化物(MXene),用扫描电子显微镜(SEM)、透射电子显微镜(TEM)及原子力显微镜(AFM)等表征了MXene的微观形貌.结果表明,所制备的MXene材料具有大片、单层及低缺陷等特点.通过抽滤MXene分散液制备的MXene膜材料具有导电性高(3280 S/cm)及韧性优异等特点.MXene膜的屏蔽性能测试结果表明,8μm厚的MXene膜屏蔽效能为60.6d B,SSE/t值则高达19531.1 d B·cm^2·g^-1.推测MXene膜的屏蔽机理是一种以吸收为主的电磁干扰屏蔽机制.

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 Ti3Al C2.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 d B with 8μm thickness and the SSE/t value is up to 19531.1 d B·cm^2·g^-1.In addition,after analyzing the electromagnetic shielding mechanism of MXene film,we know that it follows an absorption-dominant electromagnetic interference shielding mechanism.