Facile synthesis of 2D MoS2/reduced graphene oxide hybrids with excellent microwave absorption

Abstract

High-performance microwave absorption materials with tunable electromagnetic properties have long been the goal of researchers. It is still a challenge to achieve broad band absorption and lightweight performance by simply optimizing the chemical composition of absorbers. Molybdenum disulfide (MoS2) belongs to the two-dimensional transition metal disulfide with a layered structure similar to graphene. In this work, two-dimensional MoS2/reduced graphene oxide (MS/RGO) hybrids have been constructed through a convenient self-assembled hydrothermal method, in which MoS2 ultrathin nanosheets in-situ grow uniformly on the surface of RGO, constructing a unique hierarchical microstructure. Electromagnetic parameter measurements display that the dielectric behaviors of MS/RGO composites are optimized via changing the content of RGO, and meanwhile the superior microwave absorption properties are achieved with the filler-loading ratio of only 20 wt%. The widest effective absorption bandwidths (RL<−10 dB) of 5.68 GHz (12.32–18 GHz) and 6.32 GHz (11.20–17.52 GHz) are observed at a thickness of 2.0 mm for MS/RGO-10 and MS/RGO-15, respectively. When the thickness is raised to 5.0 mm, the reflection loss value of MS/RGO-10 composites reaches the minimum value of − 39.8 dB at 4.96 GHz. The improved performance can be explained by the strong interfacial polarization loss due to abundant heterogeneous interfaces, defect dipole polarization, conduction loss, and multiple reflections and scattering. The results indicate that the light-weight MS/RGO composite is considered as a promising candidate for high-performance microwave absorbers with an adequate absorption bandwidth.