Lightweight and Flexible Fe3O4/MXene/Cellulose Nanofiber Film with Gradient and Sandwich Structure for Superior EMI Shielding Properties

Nowadays, electronic equipment and wireless communication equipment are widely used,it is necessary to prepare various EMI shielding materials to eliminate the radiation pollution. In this study, a lightweight and flexible Fe ₃ O ₄ /MXene/cellulose nanofiber composite film was developed. The composite film exhibits a strong mechanical strength of 20.5 MPa. Particularly, owing to the combination of magnetic nanoparticles and two-dimensional MXenes with superb electrical conductivity, the EMI SE of the film reached 35 dB. Adding magnetic Fe ₃ O ₄ nanoparticles on the top layer of sandwich structure improves the EMI SE via increasing the value of the absorption loss, and MXene/CNF layers with different content gradients are superposed to enhance the loss of incident electromagnetic wave. The design and fabrication of Fe ₃ O ₄ /MXene/cellulose nanofiber composite film provide an environmental-friendly and facile method for EMI shielding materials, which broaden the applications of MXene-based composite materials.