Carbonization of Ni@SiC@C nanoparticles reinforced PAN nanofibers for adjustable impedance matching.

[Display omitted] • Ni@SiC@C double-shell nanoparticles were dispersed into CNFs by electrospinning. • Carbonization temperature is the critical for optimizing impedance matching. • The N-doped defect introduces extensive defects to generate dipole polarization. • The dispersed double-shell nanoparticles can provide abundant interface polarization. Achieving a broad bandwidth and efficient absorption of electromagnetic wave absorption materials remains a significant challenge, especially when considering electromagnetic pollution protection. One-dimensional carbon nanofibers with a three-dimensional network structure have been extensively studied to address this need. However, the high permittivity of carbon nanofibers results in a strong impedance mismatch with free space. In this work, we successfully dispersed double-shell Ni@SiC@C nanoparticles into one-dimensional carbon nanofibers (Ni@SiC@C CNFs) using electrospinning and heat treatment. We extensively explored the effect of carbonization temperature on the impedance matching and magnetic-dielectric loss for electromagnetic wave. The presence of rich interfaces from the double-shell nanoparticles and defects from N-doping optimizes the impedance matching of the composites. The exceptional electromagnetic wave absorption properties of the Ni@SiC@C CNFs are attributed to the synergistic effect between the three-dimensional conductive network, the interface electronic engineering induced by the sensibly loaded double-shell nanoparticles, and the multiple reflections, especially at a carbonization temperature of 600 ℃. The achieved minimum reflection loss value has been measured at an outstanding −53.27 dB, coupled with a remarkable absorption bandwidth that spans from 2.53 GHz to 18.00 GHz (15.47 GHz) across various thicknesses. These findings underscore the potential of the meticulously engineered Ni@SiC@C CNFs as highly promising candidates for efficient and broadband electromagnetic wave absorption applications. [ABSTRACT FROM AUTHOR]