1D/2D CoTe2@MoS2 composites constructed by CoTe2 nanorods and MoS2 nanosheets for efficient electromagnetic wave absorption

Rational design of the components and microstructure is regarded as an efficacious strategy for the high-performance electromagnetic wave absorbing (EMWA) materials. Herein, the CoTe2@MoS2 nanocomposites with CoTe2 nanorods and MoS2 nanosheets were synthesized via a hydrothermal method. The microstructure and composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The CoTe2@MoS2 composite was composed of stacked CoTe2 as the core and intertwined MoS2 nanosheets as the shell. The electromagnetic parameters of the CoTe2@MoS2 composites were investigated by vector network analyzer (VNA). The EMWA property of the composite showed a trend of first increasing and then decreasing with the increasing content of MoS2. When the mass ratio of MoS2 and CoTe2 was 1:1, the CoTe2@MoS2 composite exhibited the minimum reflection loss value of -68.10 dB at 4.71 GHz, and the effective absorption bandwidth value might reach 4.64 GHz (13.08-17.72 GHz) at a matching thickness of 1.60 mm with filler loading of 50 wt.%. The extraordinary EMWA property was attributed to the optimized impedance matching, multiple scattering and reflections, dipole polarization, conductive loss, and interfacial polarization. Therefore, the present approach to the design of microstructure and interface engineering offers a crucial way to construct high-performance EMW absorbers.