Dendritic Cell‐Inspired NCNTs/HEA Architecture for Synergistic Enhancement of Low‐Frequency Microwave Absorption and Thermal Conductivity

ABSTRACT With the flourishing trend toward miniaturization and high integration of electronic devices, materials that integrate both high thermal conductivity and efficient low‐frequency electromagnetic wave absorption (EMA) performance has become crucial for addressing heat accumulation and electromagnetic compatibility issue. Traditional thermally conductive EMA materials, typically fabricated by blending EMA materials with highly thermally conductive components, suffer from drawbacks such as excessive volume, high interfacial thermal resistance, and incompatibility. Herein, a cross‐scale biomimetic construction strategy was employed to successfully fabricate a dendritic cell‐liked heterogeneous architecture comprising nitrogen‐doped carbon nanotube (NCNT) networks confining high‐entropy alloy (HEA) nanoparticles. By precisely regulating the microscopic morphology of the NCNTs networks, biomimetic cross‐domain coupling channels were established, formatting a distinctive magnetic‐electric‐magnetic hierarchical loss mechanism and a 3D efficient conductive/thermal conduction pathway simultaneously. The optimized NCNTs/HEA‐2 sample achieved a minimum reflection loss (RL _min ) of −57.85 dB at 6.32 GHz, with an effective absorption bandwidth (EAB) of 2.32 GHz at a thickness of 3.10 mm. Meanwhile, the increased the in‐plane thermal conductivity of the NCNTs/HEA‐2 up to 2.44 W·m ⁻¹ ·K ⁻¹ , which are superior to those of most reported dual‐functional materials. Furthermore, the material demonstrated excellent corrosion resistance, providing a material foundation for the thermal‐electromagnetic integrated design of next‐generation electronic devices.