0D/1D Coupled CoFe@CNTs Nanocomposite Derived from ZIF-67 with Synergistic Polarization and Conductive Loss toward Highly Effective Microwave Attenuation Performance

The development of high-performance microwave absorbers with strong absorption intensity, broad absorption bandwidth, and thin matching thickness remains a focal point in the field of electromagnetic (EM) attenuation materials. The synergistic design and construction of microstructures based on multiple polarization and loss mechanisms represent an effective approach to achieve this objective. Metal–organic frameworks (MOFs) inherently possess both magnetic and dielectric capabilities, making them excellent templates for high-performance microwave absorbers. However, single-component MOF-derived absorbers still suffer from insufficient absorption efficiency and a narrow effective bandwidth. Herein, a 0D/1D composite optimization strategy combining both component design and microstructure engineering is proposed to enhance EM attenuation in MOF-derived absorbers. The design features a cubic dual-phase CoFe alloy to serve as a magnetic loss framework. Meanwhile, the in situ grown CNTs endow the nanocomposite with substantial conductive loss, as well as the enhancement of interfacial polarization and dipole polarization. The resultant CoFe@CNTs nanocomposite achieves a minimal reflection loss of −49.63 dB at 16.88 GHz (1.5 mm thickness) and 6.32 GHz EAB at 1.71 mm. Compared to single-component Co nanoparticles, the superior absorption performance with lower RL, wider bandwidth, and thinner thickness makes the CoFe@CNTs nanocomposite an ideal highly effective EM absorption candidate.