Solid and macroporous Fe₃C/N-C nanofibers with enhanced electromagnetic wave absorbability

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Microwave absorption materials are crucial for electromagnetic interference shielding.
• Developing lightweight, highly effective, and low-cost microwave absorbers remains a significant challenge.
• Iron carbide (Fe3C) nanoparticles integrated with carbon nanostructures show potential for enhanced microwave absorption properties.

Purpose of the Study:

• To synthesize and characterize solid and macroporous N-doped carbon nanofibers (NFs) embedded with Fe3C nanoparticles.
• To evaluate the microwave absorption performance of the as-prepared Fe3C/N-C NFs.
• To investigate the potential of these nanocomposites as advanced microwave absorption materials.

Main Methods:

• Electrospinning of polymer precursors followed by carbonization to create N-doped carbon nanofibers.
• In-situ formation and homogeneous dispersion of Fe3C nanoparticles within the carbon nanofiber matrix.
• Electromagnetic parameter testing to determine microwave absorption properties, including reflection loss (RL) and effective absorption bandwidth (EAB).

Main Results:

• Successfully prepared solid and macroporous Fe3C/N-C NFs with uniformly dispersed Fe3C nanoparticles.
• All synthesized materials demonstrated excellent microwave absorption performance with low filler content.
• Optimal RL of -33.4 dB at 7.6 GHz for solid Fe3C/N-C NFs.
• Effective absorption bandwidth (EAB) up to 6.2 GHz for solid Fe3C/N-C NFs-2 at 2 mm thickness.
• Macroporous Fe3C/N-C NFs achieved a broadband absorption of 4.8 GHz at 3 mm thickness.
• Broad EAB from 3.6-18.0 GHz achievable with layer thicknesses ranging from 2 to 6 mm.

Conclusions:

• The Fe3C/N-C NFs exhibit superior microwave absorption capabilities compared to many existing magnetic carbon hybrid nanocomposites.
• The combination of Fe3C nanoparticles and N-doped carbon nanofibers provides synergistic effects for enhanced electromagnetic wave attenuation.
• These Fe3C-based nanocomposites are promising candidates for lightweight, highly effective, and low-metal content microwave absorption applications in the 1-18 GHz range.