Electromagnetic wave absorbing properties of multi-wall carbon nanotube/Fe3O4 hybrid materials

Multi-wall carbon nanotube/Fe3O4 hybrids were prepared by a chemical synthesis-hydrothermal treatment method and their electromagnetic wave absorbing properties were investigated in the frequency range of 8.2–12.4 GHz (X band). As-prepared hybrids were characterized by transmission electron microscopy, X-ray diffraction and vibrating sample magnetometer. Results indicated that the surface of multi-wall carbon nanotubes was attached to magnetic Fe3O4 nanoparticles. The Fe3O4 content increased and the magnetism of the hybrids was enhanced by increasing the concentrations of Fe2+ and Fe3+ in solution. The minimum reflection loss (−18.22 dB, 12.05 GHz) was the lowest and the absorbing bandwidth was the widest when the concentrations of Fe2+ and Fe3+ were 0.02 and 0.04 M, respectively.