Two-dimensional nanosheets of MoS2: a promising material with high dielectric properties and microwave absorption performance

Abstract

In this study, few-layered MoS₂ nanosheets (MoS₂-NS) were obtained via the top-down exfoliation method from bulk MoS₂ (MoS₂-Bulk), and the dielectric properties and microwave absorption performance of MoS₂-NS were first reported. The dimension-dependent dielectric properties and microwave absorption performance of MoS₂ were investigated by presenting a comparative study between MoS₂-NS and MoS₂-Bulk. Our results show that the imaginary permittivity (ε′′) of MoS₂-NS/wax is twice as large as that of MoS₂-Bulk/wax. The minimum reflection loss (RL) value of MoS₂-NS/wax with 60 wt% loading is −38.42 dB at a thickness of 2.4 mm, which is almost 4 times higher than that of MoS₂-Bulk/wax, and the corresponding bandwidth with effective attenuation (<−10 dB) of MoS₂-NS/wax is up to 4.1 GHz (9.6–13.76 GHz). The microwave absorption performance of MoS₂-NS is comparable to those reported in carbon-related nanomaterials. The enhanced microwave absorption performance of MoS₂-NS is attributed to the defect dipole polarization arising from Mo and S vacancies and its higher specific surface area. These results suggest that MoS₂-NS is a promising candidate material not only in fundamental studies but also in practical microwave applications.