Compositional design of C-coated multi-elemental alloy nanoparticles for superior microwave absorption

Abstract

Exploring improved electromagnetic wave absorption performance in magnetic components involves capitalizing on dual dielectric relaxation and multiple magnetic resonances, ultimately giving rise to a dielectric-magnetic matching effect. Herein, a one-step Metal-organic Chemical Vapor Deposition (MOCVD) method has been utilized to fabricate C-coated ternary and quaternary alloy nanoparticles (FeCoNi, FeCoNiCu, FeCoNiMg, and FeCoNiMn) with tunable magnetization. The results affirm that the capabilities of impedance matching and electromagnetic wave attenuation can be significantly regulated by compositing nanoparticles with different elements. The optimized C-coated FeCoNiMg nanoparticles demonstrate an exceptional capacity for electromagnetic wave attenuation, achieving a reflection loss value of −51.8 dB at a matched thickness of 2.9 mm. Moreover, the absorption bandwidth significantly broadens to 7.60 GHz (10.4 – 18.0 GHz) with a thickness of 2.7 mm. The exceptional performance in electromagnetic attenuation is credited to the dielectric loss and improved impedance matching characteristics induced by the C-coated FeCoNiMg nanoparticles. The findings from this study will be beneficial in the development of lightweight and highly effective electromagnetic wave absorbers using magnetic alloy nanoparticles.