Nowadays, constructing electromagnetic wave (EMW) absorbing materials with high
absorption strength and wide response frequency is an urgent demand and also a
challenge. In this work, the bimetallic organic precursors of cobalt/iron nitrilotriacetic
acid chelate nanowires (Co/Fe-NTAC) were prepared by one-step hydrothermal self
polymerization strategy. Then, the CoxFey@C nanocomposite fibers with different
Co/Fe atomic ratios were synthesized by directly calcining the Co/Fe-NTAC
precursors. Notably, when the atomic ratio of Co/Fe is 1:1, the sample exhibits high
efficient microwave absorption performance with the minimum reflection loss (RL) of -
117.8 dB, whose effective absorption bandwidth (EAB, RL ≤ -10 dB) reaches up to
12.6 GHz (5.4-18 GHz) at the same thickness. The outstanding EMW attenuation
properties are attributed to the strong magnetic loss, multiple heterogeneous interface
polarizations, synergistic effects between magnetic cores and dielectric shells, as well
as optimal impedance matching. Especially, the heterointerfaces polarization behavior
and ferromagnetic coupling effect were verified by High-Frequency Structure Simulator
(HFSS). The Radar Cross-Sectional (RCS) values of the optimized sample are all
lower than -10 dBm2 in the range of -60?< θ < 60?, which can achieve almost full
angle coverage in the practical environment. This work provides inspiration and
strategy for the facile construction of high-intensity and ultra-wideband EMW
absorbers.