Yajing Wang, Xiuchen Wang, Meiyan Liu, Xing Rong, Siyu Fang, Zhe Liu (77240)
With the rapid evolution of intelligent battlefields and unmanned systems, multifunctional protective materials that are lightweight, flexible, mechanically robust, and capable of dynamic infrared (IR) response have drawn increasing attention. MXene (Ti₃C₂Tₓ), owing to its outstanding electromagnetic properties, is considered a promising candidate. However, its applications are restricted by poor nanosheet orientation and weak interfacial interactions during macroscopic assembly, leading to limited mechanical performance and stability. Here, we report an assembly strategy in which MXene nanosheets are heterogeneously crosslinked with waterborne thermoplastic polyurethane (TPU) and induced by blade-coating to form a large-area, stable three-dimensional (3D) interpenetrating network (IPN), greatly enhancing mechanical strength and scalability. Through hot-press integration with fabrics, a Janus flexible fabric with adaptive IR stealth and Electromagnetic Interference (EMI) shielding was fabricated. The fabric exhibits a low emissivity of 0.185 over 3–14 μm, outperforming most MXene-based composites and maintaining effective camouflage under high, ambient, and low temperatures. The opposite surface displays a high emissivity of 0.838, enabling rapid thermal release and adaptive regulation. Moreover, the Janus fabric achieves an average shielding effectiveness (SE) of 45 dB in the X-band, combined with an ultimate fabric strength of 1196 N and an ultrathin thickness of 0.4 mm, demonstrating superior overall performance compared with conventional MXene-based materials. This scalable film-construction and fabric-integration strategy provides a new platform for multifunctional protection, enabling synergistic IR stealth and EMI shielding in a lightweight, flexible structure, with broad prospects in military camouflage, electronic information security, and smart wearable systems.pol