Synthesis of ZnS quantum dots and CoFe 2 O 4 nanoparticles co-loaded with graphene nanosheets as an efficient broad band EM wave absorber

Abstract In order to obtain the high-performance electromagnetic (EM) wave absorber, nanocomposites have been applied to absorbing field. In our research, hybrid reduced graphene oxide (RGO)/CoFe 2 O 4 /ZnS nanocomposites were successfully synthesized via a facile hydrothermal process in combination with the co-precipitation route. The crystal structure, chemical composition and morphology of the as-prepared nanocomposites have been detailedly investigated. The ZnS quantum dots and CoFe 2 O 4 nanoparticles with an average diameter of 3–8 nm and 10–20 nm, respectively, were homogeneously anchored on graphene sheets. Moreover, the EM parameters of both RGO/CoFe 2 O 4 and RGO/CoFe 2 O 4 /ZnS nanocomposites were measured using a vector network analyzer. The EM wave absorption properties of RGO/CoFe 2 O 4 /ZnS nanocomposites are significantly improved compared with RGO/CoFe 2 O 4 nanocomposites, with the maximum reflection loss as high as −43.2 dB at only 1.8 mm and the maximum absorption bandwidth (