Synergistically MagneticDielectric Regulating in Binary Alloy/Carbon Nanocomposites for Electromagnetic Wave Absorption

Carbon based materials have garnered significant attention for electromagnetic wave (EMW) absorption owing to their tunable dielectric properties and lightweight nature. However, their reliance predominantly on dielectric loss mechanisms often leads to inferior impedance matching and limited absorption performance. This work presents the development of a magneto-dielectric synergistic system, where precise electromagnetic modulation is enabled by strategic compositional and interfacial engineering. Binary alloy/carbon nanocomposites are synthesized via one pot pyrolysis of metal phthalocyanines, yielding uniformly dispersed alloy nanoparticles within the nitrogen doped carbon matrix. The pyrolysis process simultaneously generates abundant heterogeneous interfaces and multiscale crystalline defects, which collectively promote strong interfacial polarization and multiple dipole relaxation. Asymmetric charge redistribution at the interfaces enhances the interfacial polarization intensity, while the multi component alloy configuration optimizes magnetic anisotropy and natural resonance. These synergistic effects enable multi-path energy dissipation, resulting in superior EMW attenuation. Remarkably, the CuNi/NC composite achieves a minimum reflection loss of – 30.5   dB and a broad effective absorption bandwidth of 5.24   GHz. Furthermore, the coatings containing CuNi/NC contributed to notable reductions in radar cross-section values, confirming its potential for practical applications. This work provides theoretical insights and a practical guideline for designing high-performance EMW absorbers through rational interface and component engineering.