Self-assembling flexible 2D carbide MXene film with tunable integrated electron migration and group relaxation toward energy storage and green EMI shielding

Delaminated Ti3C2Tx (D-Ti3C2Tx) MXene films exhibit excellent electrochemical and electromagnetic interference (EMI) shielding performance. However, the low yield and easy oxidation of D-Ti3C2Tx nanosheet limit its commercial application. Herein, the flexible green multilayered Ti3C2Tx/hydroxyethyl cellulose (M-Ti3C2Tx/HEC) composite film was successfully fabricated through the filtration assisted self-assembly of M-Ti3C2Tx together with HEC. The film shows good cyclability as electrode materials for energy storage devices, which is mainly attributed to the construction of interconnected structures, where HEC was bonded to M-Ti3C2Tx. The electron migration and surface group play important roles in the process of charging and discharging. Meanwhile, the film shows excellent EMI shielding performance. Especially, dielectric loss analysis indicates that EM waves entering the film are mainly dissipated in the form of heat energy caused by electron migration. The effect of multilayer stacking indicates that the film present the trend of absorption-dominate green EMI shielding with the decrease of the stacking thickness. This work will provide new ideas for accelerating the utilization of the MXene-based energy storage and green EMI shielding materials. (C) 2019 Elsevier Ltd. All rights reserved.