Porous coin-like Fe@MoS2 composite with optimized impedance matching for efficient microwave absorption

Magnetic metallic materials compounded with dielectric loss materials are promising for efficient microwave absorption as a result of the synergistic effect between dielectric loss and magnetic loss, as well as the optimized impedance matching. In this paper, porous coin-like structured Fe@MoS2 composite has been fabricated via solvothermal method accompanied by subsequent heat treatment under H-2/Ar atmosphere. The structure and morphology of as-prepared Fe@MoS2 composite indicates that MoS2 nanosheets with the two-dimensional (2D) structure are well dispersed on the porous coin-like Fe micro-sheets to form a core-shell structure. Particularly, the addition of MoS2 regulates the permittivity as well as improves the impedance matching of the Fe@MoS2 composite. The as-prepared composite shows efficient microwave absorption properties with the maximum effective absorption bandwidth (reflection loss below -10 dB) of about 4.73 GHz (11.13-15.86 GHz) at the corresponding coating thickness of 2.0 mm, accompanied by the minimum reflection loss of about -37.02 dB. When the calcination temperature increases to 650 degrees C, the effective microwave absorption frequency band shifts to the lower frequency (9.91-14.19 GHz) with the minimum reflection loss of about -35.5 dB under the coating thickness of 2.0 mm. Considering the efficient microwave attenuation, the as-fabricated porous coin-like Fe@MoS2 composite can be a hopeful candidate in the field of microwave absorption.