Facile synthesis of NixCo3-xS4 hollow nanoprism with broader electromagnetic absorption properties: Effect of Ni/Co atomic ratios

A suitable component with a benefited morphology is crucial to ensure the good electromagnetic absorption (EA) ability if used as electromagnetic absorber to deal with the severe electromagnetic interference crisis. In this research, NixCo3-xS4 hollow nanoprisms with tunable Ni/Co molar ratios have been successfully prepared through a simple liquid reflux and subsequently conducting a sulfidation reaction. The morphologies, crystal phase structures were analyzed by X-ray diffraction (XRD), and transmission electron microscopy (TEM). As revealed by TEM, the NixCo3-xS4 displayed hollow nanoprism shape with an average length of 1.2 μm, width of 100 nm and edge thickness of 13 nm, respectively. Afterward, the electromagnetic absorption abilities of these NixCo3-xS4 products at various x values (x = 0.2, 0.5, 0.8) were investigated in terms of the theory of transmission lines. The results demonstrated that the bandwidth ((RL ≤ −10 dB) with a specimen thickness of 2.0 mm could cover 5.6 GHz when x∼0.5, which is much greater than Ni0.2Co2.8S4 and Ni0.8Co2.2S4 filling layers. The electromagnetic loss mechanism was discussed in depth, which was correlated with molar ratios, and unique hollow nanoprism structure.