Sandwich structured cellulose-based composite for electromagnetic interference shielding, infrared stealth and Joule heating

Abstract

In response to the escalating threat of electromagnetic pollution, there has been a growing focus on the development of electromagnetic interference (EMI) shielding materials. Particularly, renewable components and proper structure are favored to design EMI shielding materials. Herein, polysaccharides (i.e., TEMPO oxidized cellulose nanofiber and cationic starch) and cellulose paper were applied to fabricate a composite with the sandwich structure of “conductor-magnet-conductor” by integrating with Ti₃C₂T_x and Fe₃O₄. This cellulose-based composite exhibited good flexibility and tensile strength. The sandwich structure enhanced the electromagnetic wave loss, owing to interfacial reflection, dielectric loss, and magnetic loss. The composite achieved an EMI shielding effectiveness (SE) of 62.9 dB. It also possessed a satisfactory infrared stealth performance due to the low infrared emissivity of Ti₃C₂T_x, which could effectively block infrared radiation from the heated object. Furthermore, the composite exhibited good Joule heating performance (reaching 104.8 °C within 25 s at 5 V). This work might provide a new pathway for the design of multifunctional cellulose-based materials.