Lightweight and elastic wood-derived composites for pressure sensing and electromagnetic interference shielding

Due to the rapid development of the wearable flexible electronics industry, the demand for multifunctional materials has greatly increased; however, it is still challenging to apply wearable flexible materials across different applications while ensuring suitable performance. In this study, inspired by the structure and morphology of natural wood, a multi-channel 3D cellulose scaffold (CS) was obtained by delignification. Then, carbon nanotubes (CNTs)/MXene composite nanosheets were inserted into the CS via vacuum impregnation. Finally, a hydrophobic and multifunctional wood-derived composite (CMP/CS) was prepared by wrapping with poly (dimethylsiloxane) (PDMS). The CMP/CS composite possessed a high compressive strength of 1.53 MPa and a maximum strain at fracture of 74.1%, and also exhibited excellent electromagnetic interference (EMI) shielding performance (29.3 dB), meeting the requirements of commercial EMI shielding applications. A constructed CMP/CS sensor exhibited a high gauge factor (3.94) and good cyclic stability (over 1000 cycles) and could monitor various human movements in real-time. The thin PDMS protective layer rendered the CMP/CS composite hydrophobic and improved its durability for daily applications. Thus, this smart wood-derived composite provides a reference for studying next-generation lightweight wearable electronic devices.