Vapor diffusion synthesis of rugby-shaped CoFe₂O₄/graphene composites as absorbing materials

Rugby-shaped CoFe₂O₄/graphene composites were synthesized using a vapor diffusion method in combination with calcination. The morphologies and structures of the products were characterized by field emission scanning electron microscopy, X-ray diffractometer, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The magnetic and electromagnetic parameters were measured using a vibrating sample magnetometer and a vector network analyzer, respectively. Results show that rugby-shaped CoFe₂O₄ particles are distributed on graphene sheets. A minimum reflection loss (RL) of -39.0 dB is observed at 10.9 GHz for the sample with a thickness of 2.0 mm, and the effective absorption frequency (RL < -10 dB) ranges from 9.6 to 14.3 GHz, indicating the excellent microwave absorption performance of the products. The absorbing performance of the CoFe₂O₄ rugbies/graphene composites is better than that of the CoFe₂O₄ nanoparticles/graphene composites.