In Situ Synthesis of Heterostructured Fe–Ni Nanowires with Tunable Electromagnetic Wave Absorption Capabilities

One-dimensional iron–nickel (Fe–Ni) heterogeneous nanowires with superior electromagnetic wave (EMW) absorption were successfully prepared by a magnetic-field-assisted liquid-phase reduction method. The electromagnetic properties of the absorber were controllably tuned by changing the atomic molar ratio of Fe to Ni. The composite with an Fe:Ni atomic molar ratio of 1:1.5 exhibited the finest EMW absorption characteristics. With a matched thickness of 2.175 mm, the minimum reflection loss (RLmin) at 18 GHz can be as high as 26.106 dB. Also, the majority of the Ku-band is covered by the effective absorption bandwidth (EAB, RL ≤ −10 dB), which is up to 6.08 GHz at 2.6 mm with a filler content of 25%. The excellent absorber performance is due to one's own rich heterogeneous interface to conciliate the dielectric and magnetic losses. The successful exploration of the one-dimensional heterogeneous structure EMW absorber provides important insights for the future sensible fabrication of absorbers with excellent EMW absorption capability.