Multilayer assembly of strong and tough MXene/cellulose films for excellent electromagnetic shielding

The prosperity of modern communication and wearable electronics has greatly necessitated the development of films that could feature both electromagnetic interference shielding and mechanical flexibility. Inspired by the strong interaction between cellulose nano fiber (CNF) and MXene nanosheet, as well as the unique magnetism of Co/C nano particles, here we report a series of CoC@CNF/MXene films prepared through alternative vacuum filtration. Owing to the unique alternative multilayered structure, where the conductive MXene nanosheets are selectively distributed between magnetic CoC@CNF layers, the resultant CoC@CNF/MXene multilayer film presents a maximum EMI SE of 37.1 dB, together with extremely high absorption capacity (over 95 %). Meanwhile, excellent electro-thermal conversion capacity that allows for fast thermal response (5 s) is achieved. Benefiting from this, a portable and low voltage-driving deicing device was successfully designed. Moreover, the satisfying flexibility has enabled these multilayer structured films to sustain repetitive bending, folding and shaping. Herein, this research has opened up new horizon in seeking both superior EMI shielding and mechanical performance through design of multilayered structure, which will further benefit the development of MXene‑based composites for high-performance electronic devices.