Fabrication and electromagnetic wave absorption properties of RGO/Fe3O4/FeCO3-based composite

RGO/Fe 3 O 4 /FeCO 3 -based composite was prepared by a one-step hydrothermal method. The microscopic morphology and structure were studied using analytical techniques including scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electromagnetic parameters and the wave absorption properties of the composite/paraffin mixture were analyzed by the vector network analyzer. It is divulged that the FeCO 3 spheres, Fe 3 O 4 spheres, and the RGO sheets form a fluffy structure rich in microscopic cavities, as well as a good conductive network through the sphere–sheet and sphere–sphere interlap mechanisms, which significantly improves the absorbing performance of the composite. The composite can achieve a maximum reflection loss of − 37.9 dB at a frequency value of 13.9 GHz with a matching thickness of only 6.8 mm. The matching thickness can be adjusted in the range of 5.2–10.0 mm in order to attain a flexible adjustment of the effective microwave absorption band of 9.9–18.0 GHz. Combined with the first-principles calculations, compositing reduces the electron migration energy barrier and thus improves the charge transferring capability. Meanwhile, the interaction of the different components leads to the formation of a special charge transferring channel and the increase of carrier concentration, which enhances the charge transport, as well as the absorbing capacity of the absorbing material.