A novel double 3D continuous phase composite with ultra-broadband wave absorption from gigahertz to UV–vis-NIR for extremely cold environment

Multifunctional integration is of great significance for solving certain practical engineering application problems. Here, an ultra-broadband electromagnetic wave absorption (EWA) composite with unique double three-dimensional (3D) continuous phase is constructed for being applied in extremely cold environment. Notably, Co1.29Ni1.71O4/reduced graphene oxide/carbon foam (Co1.29Ni1.71O4/rGO/CF) composite exhibits excellent EWA properties with a minimum reflection loss of −63.14 dB at a thickness of 3.0 mm, and effective absorption bandwidth can reach 7.25 GHz in microwave frequency range. Besides, the composite acquires perfect terahertz wave absorption performance in 0.8–2.0THz frequency range and also manifests outstanding ultraviolet–visible light-near infrared (UV–vis-NIR) absorption within 250–2500 nm, verifying their ultra-broadband EWA performance. Moreover, when exposed to 1 sun illumination, the composites temperature would rapidly rise to 90 °C within 1 min and also manifest great up-down temperature stability in multiple repeated illumination cycles. This work provides inspiration for developing multifunctional EWA composites with both ultra-broadband high-efficiency absorption properties and superior extreme environmental adaptability.