Three-Dimensional Carbon Networks Decorated with CoFe2O4 Nanoparticles Composites: Fabrication and Broadband Electromagnetic Wave Absorption Performance

A novel electromagnetic wave absorber of three-dimensional carbon networks decorated with CoFe2O4 nanoparticles (3DC/CoFe2O4) was prepared through a simple freeze-drying method followed by a high-temperature calcination process. The 3DC/CoFe2O4 composite prepared at 630 °C (S630) exhibits broadband electromagnetic wave absorption with only 20 wt% filler loading. The effective absorption bandwidth (reflection loss [RL] < −10 dB) of S630 reaches up 6.63 GHz, and the minimum RL of −19.5 dB is obtained at 15.45 GHz when the matching thickness is 2.5 mm. The excellent electromagnetic wave absorption performance of the 3DC/CoFe2O4 composite can be attributed to good impedance matching and strong attenuation capacity.