Preparation and low-frequency microwave-absorbing properties of MWCNTs/Co–Ni/Fe₃O₄ hybrid material

MWCNTs/Co–Ni/Fe₃O₄ hybrid material has been successfully prepared by electroless plating and coprecipitation method, which is applied to the low-frequency microwave absorption. Their surface morphology, structure, magnetism and electromagnetic properties in the low-frequency range of 1–4[Formula: see text]GHz were characterized by field-emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and vector network analyzer. Results indicated that magnetic Co–Ni/Fe₃O₄ particles were attached on the surface of multi-walled carbon nanotubes successfully. The saturation magnetization of MWCNTs/Co–Ni/Fe₃O₄ hybrid materials was 68.6[Formula: see text]emu/g and the coercivity is 17.9 Oe. The electromagnetic and microwave absorbing properties analysis in the low-frequency range of 1–4[Formula: see text]GHz indicated that the hybrid material exhibited excellent magnetic loss and the maximum reflection loss could reach [Formula: see text][Formula: see text]dB at 1.51GHz with 1.05[Formula: see text]GHz bandwidth below [Formula: see text][Formula: see text]dB.