A carbon fiber based three-phase heterostructure composite CF/Co0.2Fe2.8O4/PANI as an efficient electromagnetic wave absorber in the Ku band

A three-phase heterostructure composite CF/Co0.2Fe2.8O4/PANI with a layer by layer (LBL) structure was designed and synthesized for achieving improvement in electromagnetic (EM) wave attenuation of carbon fiber (CF). The structure and morphology analyses demonstrated the LBL structure of the absorber. The electromagnetic parameters of the absorber and wax composite were measured at 2–18 GHz to evaluate its EM wave attenuation performance. The three-phase heterostructures absorber CF/Co0.2Fe2.8O4/PANI demonstrated the highest attenuation effectiveness value of −38.2 dB (>99.9% attenuation) at 12.7 GHz with a thickness of 4.1 mm. Moreover, for CF/Co0.2Fe2.8O4/PANI, with an absorber thickness of 3.1–4.1 mm, the minimum RL values are all lower than −20 dB in Ku band. The excellent EM wave absorbency in the Ku band for CF/Co0.2Fe2.8O4/PANI results from the combined effect of magnetic loss and dielectric loss by introducing more phase onto CF. Considering the EM wave absorption performance and the effortless fabrication process, it is believable that by introducing more specially designed phases, the EM wave attenuation performance of CF can be significantly improved.