Controllable Coating of Polypyrrole on Silicon Carbide Nanowires as a Core–Shell Nanostructure: A Facile Method To Enhance Attenuation Characteristics against Electromagnetic Radiation

Continuous polypyrrole (PPy) shells were coated on silicon carbide (SiC) nanowires to form core–shell nanostructures, and the thicknesses of the shells were efficiently tuned through controlling the rate of polymerization. Compared with the composites loaded with pure SiC nanowires, the values of ε′ and ε″ for the composites loaded with PPy@SiC nanowires were strengthened remarkably along with the increased thickness of the shells. The electromagnetic absorption (EA) bandwidths lower than −10 and −20 dB can be monitored in the area of 3.67–18.00 and 4.13–18.00 GHz, when 5 wt % of PPy@SiC nanowires were loaded in the composite. Meanwhile, the effective EA bandwidth can reach 6.88 GHz, and the strongest reflection loss is −58.6 dB.