Self-assembly of one-dimensional cobalt-carbon to turn dielectric properties for electromagnetic attenuation

An in situ self-assembly strategy for core-shell nanostructures in a nanofiber is proposed to tailor the electromagnetic attenuation performance of cobalt-carbon heterogeneous materials. Due to the atomic step induction on the surface of the cobalt nanoparticles and the interaction of the cobalt electron orbitals with the unsaturated sp² orbitals of the graphitized structure island, self-assembly of the shell initiates by incorporating carbon atoms. With the process of self-assembly, electron transport channels and heterogeneous interfaces can be tailored to synergistically modulate the conductivity and polarization relaxation. Combining the dual modulating effect, impedance matching and electromagnetic attenuation performance can be dominated. As a result, an optimal reflection loss (RL) of −50.3 dB and shielding effectiveness (SE) of 32.4 dB are obtained, demonstrating the versatility and adjustability of the nanofiber. This work provides an in-depth analysis of the relationship between crystal engineering and electromagnetic properties of the core-shell nanomaterials.