Multifunctional lightweight rGO/polyimide hybrid aerogels for highly efficient infrared-radar-acoustic compatibility via heterogeneous interface engineering strategies

Abstract

The development of infrared-radar-acoustic compatible materials faces numerous challenges due to the conflicting properties required for infrared and radar stealth, as well as the differences in energy loss mechanisms between radar waves and acoustic waves. To this end, heterogeneous interface engineering strategies were proposed to design lightweight hybrid aerogels. Reduced graphene oxide (rGO) was used as a functional component, and water-soluble polyimide was applied as a mechanical reinforcement matrix, aiming to integrate the advantages of the dual components and the 2D/3D multiple heterogeneous interfaces. The sample exhibits outstanding mechanical elasticity, thermal insulation performance, and infrared-radar-acoustic-compatible stealth. Its infrared emissivity was reduced by 0.311 and 0.024 in the two atmospheric window bands of 3–5 and 8–14 μm, respectively. The minimum reflection loss (RL_min) value can reach –48.86 dB, and the effective absorption bandwidth can cover the entire tested X-band. Through CST simulation of radar stealth performance in the 2–30 GHz range, an RL_min value of –48.85 dB and an optimal absorption bandwidth of up to 10.19 GHz can be achieved. Additionally, at a low frequency of 63 Hz, the material achieves the maximum sound absorption coefficient of 0.457. This study provides an innovative approach to the development of high-performance stealth materials with infrared-radar-acoustic compatibility.