Biomimetic Feather‐Inspired CuHBT Superhydrophobic Hierarchical Architectures for Dual‐Protection Excellence in High‐Performance Microwave Absorption and Corrosion Resistance

Abstract Despite remarkable advancements in microwave absorption materials (MAMs) for electromagnetic shielding, achieving the synergistic fusion of efficient microwave absorption and enduring corrosion resistance persists as a daunting scientific challenge. While conventional multi‐phase composite strategies attain dual‐protection functionality, persistent intrinsic property mismatches fundamentally undermine the reconciliation of MA performance and anti‐corrosion capabilities. Thus, pioneering structural engineering of single‐component systems to simultaneously enable electromagnetic attenuation and corrosion resistance emerges as a transformative frontier. Drawing inspiration from ingenuity in feather wing hierarchies, a breakthrough ligand exchange strategy is pioneered to meticulously engineer 2D stacked Cu/4‐hydroxyphenylthiol (CuHBT) superhydrophobic nanosheets with multiscale morphological tunability through precise stoichiometric modulation. The optimized CuHBT‐2 manifested exceptional MA performance, delivering a remarkable minimal reflection loss ( RL min ) of −53.06 dB at 2.9 mm thickness alongside a record‐breaking ultra‐wide effective absorption bandwidth (EAB) of 8.80 GHz spanning X and Ku bands. This extraordinary achievement arises from its hierarchical stacked architecture, which artfully extends electromagnetic wave propagation pathways while amplifying interlayer polarization‐governed dielectric dissipation. Moreover, CuHBT‐2‐0.7% coatings exhibited outstanding corrosion resistance, maintaining an impressive 92.88% protection efficiency after 21 days of rigorous salt spray testing, triumph stemming from the synergistic interplay of a robust 2D physical barrier and coordination‐activated sacrificial passivation dynamics.