Ordered heterostructured aerogel for multi-spectra stealth in microwave, infrared and visible light bands

Achieving multi-spectra stealth is an important way to improve the battlefield survivability of weapons and equipment, whereas it remains challenging to cope with the synergy detection spanning microwave, infrared, and visible bands. Herein, a chitosan-derived carbon/reduced graphene oxide (rGO)/carbon nanotubes (CNTs)/Co nanoparticles/SnS2/SnS aerogel with ordered 3D multi-layer structure (CRCCS2) was fabricated by bidirectional freeze-drying, chemical bath deposition, and heat treatment. The construction of ordered multi-layer carbon walls can not only extend the transmission path of electromagnetic waves (EMWs), but also accelerate the hopping and migrating of electrons, causing the enhanced microwave attenuation. Moreover, the introduction of SnS-SnS2 heterostructure in the CRCCS2 sample induces a larger number of heterogenous interfaces, C defects and S vacancies, meanwhile, the internal electric field is constructed, leading to high conductivity loss and polarization loss. Thus, the CRCCS2 aerogel exhibits an outstanding microwave absorption performance with an ultra-broad effective absorption bandwidth (EAB) of 8.4 GHz and a minimal reflection loss (RLmin) of -56.1 dB with an ultra-low filling ratio of 4.7 wt%. Benefiting from the heat-transfer suppression (thermal conductivity = 0.05 W m(-1) K-1) and electrothermal conversion (temperature regulation from 25 to 98 degrees C), the CRCCS2 aerogel achieves both passive and active infrared stealth. In addition, the CRCCS2 sample offers a low reflectivity (<20 %) in the range of 250-2400 nm, guaranteeing an excellent stealth ability of visible light. This study provides a promising strategy for fabricating the multi-spectra stealth materials that can counter the multiband surveillance.