MOFs self-templated hollow Co/NC@PANI composites for high-efficiency electromagnetic absorption

Abstract

Considering the diverse structures and superior properties of metal-organic frameworks (MOFs), we successfully synthesized Co/NC@PANI composites through high-temperature pyrolysis and in-situ chemical oxidation using zeolitic imidazolate framework compounds (ZIFs) as precursors. The inclusion of polyaniline in the composites improved conductive loss and interfacial polarization, while the porous structure of Co/NC and uniformly dispersed cobalt nanoparticles can contribute to electromagnetic wave multiple reflection and magnetic loss. By synergistically dissipating electromagnetic waves through various loss mechanisms, we were able to control electromagnetic parameters and optimize performance, resulting in the development of Co/NC@PANI composites with exceptional electromagnetic properties. The minimum reflection loss (RLmin) reaches − 46.28 dB at 5.76 GHz, with a matching thickness of 5 mm. And the effective absorption bandwidth (EAB, RL<− 10 dB) reaches 3.52 GHz at a thickness of 2.5 mm. This work provides an efficient enlightenment for constructing microwave-absorbing material with high performance.