Hierarchical ZnFe2O4@RGO@CuS composite: Strong absorption and wide frequency absorption properties

In this work, hierarchical ZnFe2O4@RGO@CuS composite was synthesized by a simple two-step hydrothermal route, and its constitution, microstructures and microwave absorption properties were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and vector network analyzer (VNA). Experimental results show that hierarchical ZnFe2O4@RGO@CuS composite exhibits an enhanced electromagnetic wave attenuation capacity, which is ascribed to the suitable impedance match, magnetic loss, dielectric loss and special hierarchical nanostructure. Importantly, the three-dimensional flower-like structure of CuS can produce more multiple reflection and scattering, leading to more consumption of electromagnetic wave energy. The maximum reflection loss of ZnFe2O4@RGO @CuS composite reaches - 55.4 dB at 14.6 GHz and the effective absorption bandwidth (< -10 dB) is as wide as 7.5 GHz (from 10.5 to 18 GHz) for a thickness of only 2.2 mm. Hence, the as-prepared nanocomposite with strong absorption and wide frequency can be a promising absorber in decreasing EM wave interference.