Radial Interface Sequence Coordination Regulates Impedance Matching and Interface Polarization for Microwave Attenuation

ABSTRACT Highly conductive carbon fibers are promising for ultra‐thin microwave absorption (MA), but the significant impedance mismatch limits microwave incidence and subsequent energy dissipation. Conventional interface engineering largely optimizes component composition and loading, whereas the role of radial interface order remains unclear. In this work, the interface sequence is treated as a new structural variable. ZIF‐67 and MIL‐88B nanolayers with tunable electromagnetic (EM) responses were synthesized in situ on carbon fibers. First, the impedance mismatch characteristics of carbon fibers were improved by adjusting the heat treatment temperature and shell loading. Furthermore, the EM response properties of the materials were finely tuned by reversing the growth order of ZIF‐67 and MIL‐88B on the surface. The optimized CFC‐9‐2 achieved minimum reflection loss (RL) of −70.81 dB and effective absorption bandwidth (EAB) of 4.85 GHz at a thickness of 1.58 mm. Further simulations of far‐field conditions and near‐field Wi‐Fi radiation tests demonstrate attenuation in representative environments. The results demonstrate that the spatial sequence of interfaces serves as a key structural parameter for regulating the transmission and dissipation of electromagnetic energy.