Microwave permeability of Ni nanoplatelet composites

Microwave permeability of the composites made by dispersing 13.7–35.8 vol% random orientated Ni nanoplatelets in nonmagnetic insulating matrix was studied in the frequency range of 0.1–10 GHz. The effect of the Ni nanoplatelet volume fraction on the microwave permeability of the composites has been studied. With decreasing Ni nanoplatelet volume fraction, the resonance peaks of the microwave permeability shift toward higher frequency and have a better resolution. The Ni nanoplatelet composites show three overlapped resonance peaks in the frequency range of 0.1–10 GHz. The first resonance peak can be related to the natural resonance and the other resonance peaks in higher frequency range may be attributed to exchange resonance. Compared to the Bruggeman effective medium theory, the isotropic model of the magnetic susceptibility developed by Chevalier et al. is more suitable to describe the microwave permeability of the Ni nanoplatelet composites.

► Microwave properties of the Ni nanoplatelet composites were studied.
► Ni nanoplatelet composites show multi-resonant behavior of microwave permeability.
► Two effective medium models were used to describe the microwave permeability.