MXene Functionalized Wood Composite Films for Efficient Electromagnetic Interference Shielding and Pressure Sensing

Designing ultra-light, green, and flexible films for efficient electromagnetic interference (EMI) shielding is crucial yet challenging. Herein, laminated Ti3C2Tx MXene nanosheets are prepared and impregnated into a delignified wood matrix to fabricate composite films. Through a facile drop-casting and densification strategy, highly aligned cellulose fibers are used for regulating the stacking behavior of MXenes, and the MXenes are encapsulated and attached tightly to the cellulose chains through hydrogen bonds. A high MXene loading up to 32.5 wt.% can be realized, and the resultant MXene/wood film exhibits a tensile strength of 260.7 MPa. The EMI shielding effectiveness is calculated to be 55.5 dB (X-band, 8.2-12.4 GHz), with a normalized surface-specific shielding effectiveness of 2673.4 B cm2 g-1. Moreover, the superior electrical conductivity and structural robustness of the composite film give it pressure-sensing properties and show high sensitivity for monitoring diverse human physiological movements. MXene nanosheets are integrated into delignified wood through a drop-casting and densification strategy to form functional films for efficient electromagnetic interference shielding and pressure sensing.image