Binary and ternary ferromagnetic alloy/C nanocapsules for improved X-band microwave absorption

Abstract

The dielectric-magnetic matching effect emerges from the presence of dual dielectric relaxation and multiple magnetic resonances. This phenomenon becomes a strategic approach in the quest to enhance microwave absorption (MA) performance by optimizing magnetic components. Herein, binary and ternary ferromagnetic alloy with tunable components embedded in carbon skeleton (core/shell) nanocapsules has been successfully fabricated by one step metal-organic chemical vapor deposition (MOCVD). The core/shell structure design introduces numerous interfaces that amplify dielectric loss stemming from polarization. It is important to emphasize that modifying the composition of magnetic core in these nanocapsules effectively regulates the impedance matching characteristics. As a result, the CoFeNi/C nanocapsules demonstrate an optimal reflection loss (RLmin) of -53.6 dB at a thickness of 2.55 mm, alongside an effective absorption bandwidth (EAB) of 5.92 GHz at a thickness of 2.05 mm, with a filling ratio as low as 20 wt%. This study has provided valuable insights into a promising avenue for fabricating dielectric-magnetic nanocomposites with outstanding microwave attenuation capabilities through the manipulation of composited elements.

Facile synthesis of eco-friendly mango peel-derived porous carbon for optimizing microwave absorption

“…A considerable number of microwaves are reflected at the surface of the sample as a result of poor impedance matching, which ultimately results in insufficient microwave absorption. Impedance matching and microwave attenuation inside the composite material play significant roles in microwave absorption [56]. A larger portion of the microwave wave can propagate inside the composite thanks to improved impedance matching, which reduces direct reflections.…”