Highly compatible ZIF-11 MOF-embedded carbon foam nanocomposites for efficient electromagnetic wave absorption

Abstract

Developing lightweight, high-performance materials for effective electromagnetic wave (EMW) absorption is crucial for the mitigation of adverse exposure to high-frequency electromagnetic radiation. In this study, we present a novel approach to achieve wide-range EM wave attenuation in the radar range (X-band) through the incorporation of a ZIF-11 MOF porous architecture in a carbon foam (CF), forming a heterogeneous distribution to enhance interface polarization and facilitate strong electromagnetic wave absorption. The structural features and composition of the synthesized hybrid composites were characterized using XRD, SEM, FTIR spectroscopy, and TGA. With precise control over variable MOF loadings, the 12% ZIF-11/CF composite achieved the best optimal EMW absorption, exhibiting a notable reflection loss of −49.12 dB with a broad effective absorption bandwidth of 4.2 GHz at 2 mm thickness, indicating 99.99% absorption and covering almost the entire X band. The porous structure of the ZIF-11/carbon foam composite was found to be ideally suited to promote multiple scattering and enhance dielectric loss, yielding improved impedance matching across the X band. Additionally, the lightweight structure maintained structural integrity, offering a promising balance of effective EM wave attenuation and low material density. This work highlights the potential of MOF-incorporated carbon composites for high-performance EMW absorption, thus providing a scalable pathway toward advanced applications in electronic, healthcare and defense technologies through effective electromagnetic interference (EMI) reduction.