Rational construction of iron nanowire dip-coated melamine composite foams for integrated electromagnetic wave absorption and thermal management

Developing microwave-infrared compatible stealth porous foams is highly desirable for practical applications in areas of aerospace, military, and wearable electronics. Herein, a lightweight and dual-functional three-dimensional conductive network was constructed by assembling one-dimensional iron nanowires (FeNWs) on the porous melamine foam (MF) skeleton via one-step vacuum-assisted impregnation strategy. Benefiting from inherent porous structure, multi-scale heterogeneous interface, and strong magnetic-dielectric synergy, the as-developed MF@FeNWs composite foam exhibited superb electromagnetic wave absorption capacity with a minimum reflection loss of -36.5dB and an effective absorption bandwidth of 2.4GHz. Moreover, the composite foam possessed outstanding mechanical stability under the dynamic compressive cycles. More importantly, due to its low thermal conductivity of 0.0589W/mK, the foam’s surface saturation temperature remained nearly unchanged after persistent heating at 65 °C for over 1h. Such remarkable results were largely attributed to the exceptional infrared stealth and thermal insulation characteristics. This study will provide new insights for rationally constructing the reliable composite foam materials to cater to the application requirements for various fields.