Engineering the electronic structure on MXenes via multidimensional component interlayer insertion for enhanced electromagnetic shielding

MXene-based functional electromagnetic interference (EMI) shielding films are highly desirable for modern integrated electronic and telecommunication systems in aerospace, military, artificial intelligence, and smart and wearable electronics field. In this work, 3D freestanding Ti3C2Tx/CNTs/Ni film assembled by 1D multi-walled carbon nanotubes (MWCNTs)/Ni and 2D Ti3C2Tx MXene sheets was synthesized by a facile vacuum filtration process. By electrostatic incorporation, hexagonal nickel plates embed on the CNTs and then the CNTs/Ni insert into the Ti3C2Tx layers to form magnetized Ti3C2Tx-based functional film with a compact and laminated structure. Due to the outstanding electron migration capacity in the highly conductive Ti3C2Tx sheet and multiple internal reflections from porous and segregated structures, the optimized Ti3C2Tx/CNTs/Ni composite films show excellent EMI shielding effectiveness of 67.4 dB with electrical conductivity of 744 S cm–1. Surprisingly, a magnetization compensation strategy is built to boost the EMI shielding effectiveness with decreased conductivity. Meanwhile, the visual magnetic coupling phenomenon and charge distribution in the heterogeneous interfaces could be observed in the reconstructed electron holography images. Those encouraging results shed light on novel magnetized MXene-based functional films for high-performance EMI shielding.