Facile synthesis of Fe/Fe3C-C core-shell nanoparticles as a high-efficiency microwave absorber.

The combination of ferrite and carbon materials with core-shell nanostructures has attracted tremendous interest in microwave absorption field. Herein, Fe/Fe 3 C-C core-shell nanoparticles with diameters of 10–70 nm were synthesized by one-step metal-organic chemical vapor deposition. The nanocores of the nanoparticles can be tailored from Fe 3 C, to Fe 3 C/Fe, and then Fe by simply changing the reaction temperature. The Fe/Fe 3 C-C core-shell nanoparticles exhibited an optimal reflection loss (RL) value of −58.5 dB and effective absorption bandwidth (frequency range for RL < − 10 dB) of 6.2 GHz at a low thickness of 2.0 mm. The microwave absorption performances of the as-synthesized Fe/Fe 3 C-C core-shell composites could be easily tuned by the phase composition of nanocores. The achieved results demonstrated that the as-synthesized Fe/Fe 3 C-C core-shell nanoparticles have considerable potential as an effective microwave absorber with tunable absorption performance. • Fe/Fe 3 C-C core-shell NPs are fabricated by MOCVD on a large scale. • The phase composition of nanocores are tailored from Fe 3 C, to Fe/Fe 3 C, and then to Fe, by changing the reaction temperature. • Fe/Fe 3 C-C core-shell NPs have an RL value of -58.5 dB and an BW eff value of 6.2 GHz at a thin thickness of 2.0 mm. • Phase control of nanocores is demonstrated to be effective way to tailor the MA properties of the as-synthesized NPs. [ABSTRACT FROM AUTHOR]