A metal-organic framework template-assisted strategy is used to construct a broadband flexible electromagnetic wave-absorbing film with rich heterogeneous interfaces

Abstract

The development of broadband microwave absorbers has continuously faced the dual challenges of structural design complexity and insufficient functional integration. To significantly enhance electromagnetic wave attenuation capability and systematically broaden absorption bandwidth, this work proposes an innovative heterogeneous-interface engineering strategy based on magnetoelectric coupling enhancement. Co/C composite nanofiber materials enriched with abundant heterogeneous interfaces were fabricated by first loading Co²⁺ in situ onto polymer fiber surfaces via electrospinning, followed by high-temperature solid-phase sintering. Exceptional electromagnetic wave absorption performance was obtained by optimizing the calcination temperature and adjusting the filler content ratio. CNC-700 achieved a peak reflection loss of −53.59dB at a filling ratio of 30%. At a filling ratio of 25%, CNC-700 displayed a maximum effective absorption bandwidth (EAB) of 7.2GHz, fully covering the Ku-band. Meanwhile, CNC-700 was also found to exhibit excellent electromagnetic wave absorption performance in both X-band and Ku-band. The exceptional performance in absorbing electromagnetic waves stems from the optimal balance achieved between dielectric dissipation and magnetic attenuation. The composite fiber material developed in this work can effectively mitigate electromagnetic interference, providing a novel structural design paradigm for developing electromagnetic shielding materials.