Bifunctional Hierarchical Composite Nanofiber Membranes for Infrared Thermal Camouflage and Electromagnetic Shielding

Electrospun nanofiber membranes (NFMs) have shown great potential in infrared thermal camouflage (ITC) and electromagnetic shielding (EMS) due to their advantages of high specific surface area, lightweight, and superior flexibility. In this work, based on the spherical section free surface electrospinning technology for the efficient preparation of NFMs, combined with functional modification methods, the hierarchical composite NFMs with dual functions of ITC and EMS were fabricated, and their dual-function optimization and synergistic mechanism were explored. Among them, the NFMs loaded with phase change nanoparticles (NPs) prepared by adsorbing polyethylene glycol (PEG) on mesoporous SiO 2 (H-SiO 2 ) offered ITC function, while the multilevel porous structured NFMs containing alloy-based porous nanospheres derived from spherical metal organic frameworks (CoCuZn MOFs) provided excellent EMS function. After stabilizing on a 60 °C heating platform for 10 min, the temperature difference between the average temperature of the hierarchical composite NFM and the heating platform reached 14.9 °C, and its average specific shielding efficiency reached 9083.22 dB·cm 2 ·g –1 . This indicated that by regulating the composition, structure, and morphology of electrospun NFMs, their effective modulation of thermal radiation and electromagnetic waves could be achieved, thus providing an idea for the design and preparation of high-performance bifunctional materials.