Stabilized and Conductive MXene Films via Dual Biopolymer Modification for Long‑Term Electromagnetic Interference Shielding and Infrared Camouflage

MXene demonstrates considerable potential in the domains of electromagnetic interference (EMI) shielding and infrared camouflage due to its inherently high electrical conductivity. However, its vulnerability to structural and functional degradation under humid-thermal conditions severely limits its practical application. Herein, a synergistic dual-strategy design is proposed for the fabrication of a stable MXene-based film with enhanced oxidation resistance. Through dual modification with sodium lignosulfonate (LS) and tannic acid (TA), the antioxidative capability and mechanical strength of MXene are cooperatively enhanced. Moreover, by constructing conductive pathways between MXene layers via Al3+ ionic intercalation, the conductivity compromised by polymer addition is effectively restored, a mechanism that is further substantiated by DFT calculations. It is evident that the rational design of the MXene/LS/PTA-Al3+ film exhibits remarkable oxidation stability. Following a 30 day aging process in a humid-thermal environment, the film retains 92.18% of its original EMI shielding effectiveness, while the infrared emissivity undergoes only a marginal increase from 0.15 to 0.22, demonstrating excellent structural and functional durability. Consequently, the highly stable MXene/LS/PTA-Al3+ film has significant potential as a durable electromagnetic-infrared compatible stealth material.