One-step construction of low-dimensional hybrid carbon networks embedded with magnetic Fe nanoparticles for efficient microwave absorption

Low-dimensional hybrid carbon networks with high electrical conductivity and low density are essential for designing lightweight and efficient microwave absorbing materials (MAMs). In this study, low-dimensional hybrid carbon networks with tailorable electromagnetic properties were successfully fabricated by a one-step method. These networks consist of (i) magnetic Fe nanoparticle-embedded, two-dimensional (2D) carbon lamellar structure and (ii) intertwined one-dimensional (1D) carbon nanotubes grown on the structure. These 1D-2D hybrid networks exhibit excellent electron transport, enhanced interfacial polarization, multiple loss mechanisms, and improved impedance matching. Consequently, they significantly boost MAM performance. With a 30 wt% absorbent filling fraction, the material achieves a reflection loss of less than − 10 dB across a frequency range of 5.0 GHz in the Ku band, with a matching thickness of only 1.67 mm. By tuning absorber thickness from 1.0 to 5.0 mm, the effective absorption bandwidth can reach up to 14.3 GHz, covering 89 % of the frequency range measured, and achieving a bandwidth of 10.0 GHz with 99 % absorption intensity. These results underscore a simple and effective strategy to construct low-dimensional hybrid carbon networks having tunable electromagnetic properties, that offers a promising pathway for the design of lightweight, broadband and efficient MAMs.