Study On The Synthesis And Performance Of Fe-MoS₂-based Nanocomposites

Since the synthesis of graphene,two-dimensional layered materials have become the focus of researchers all over the world in recent years due to their excellent physical and chemical properties,and great potential applications in new energy and optoelectronic devices.As a very promising new two-dimensional material,molybdenum disulfide?MoS₂?nanosheets can display excellent properties such as high light absorption,photocatalysis and electrocatalysis.Therefore,the research on MoS₂ nanosheets has attracted much attention in recent years.In addition,it is well known that dielectric loss and magnetic loss are the main ways and approachs for the attenuation of electromagnetic waves.In order to make full use of these two loss mechanisms,their synergistic and interfacial effects,in this paper,we use Fe-MoS₂based composites as the research object to construct and synthesize the mixed-dimensional MoS₂-based magnetic van der Waals heterostructures and core@shellstructuredFe3O4@MoS2nanocomposites.Moreover,their electromagnetic and microwave absorption properties was systematically studied.The specific research work is as follows:?1?The synthesis and microwave absorption properties of magnetic MoS₂-based van der Waals heterostructures:In this study,we constructed and synthesized the composites with the desired structures and components by the methods of hydrothermal treatment and chemical vapor deposition.Firstly,the Fe₃O₄-MoS₂nanocomposites was synthesized by hydrothermal method.Then,using the obtained Fe₃O₄-MoS₂ as the catalyst precursor and,the effects of temperature on the microstructure,electromagnetic and microwave absorption properties of MoS₂-based van der Waals heterostructures generated by the method of chemical vapor deposition were systematically investigated.The obtained results showed that“3-0-2”type C-Fe₃O₄-MoS₂ and“1-0-2”type CNTs-Fe@Fe₃C-MoS₂ van der Waals heterojunction could be synthesized at 400 ^oC and 500 ^oC,respectively.?2?The synthesis and microwave absorption properties of core@shell structured Fe₃O₄@MoS₂ nanocomposites:Based on the previous work,in order to synthesize Fe₃O₄-MoS₂ composites with superior microwave absorption properties,we synthesized the core@shell structured Fe₃O₄@MoS₂ nanocomposite by two-step hydrothermal method.Firstly,Fe₃O₄ nanoparticles were synthesized by hydrothermal method using sodium acetate and ferric chloride as starting materials.Then,using ammonium molybdate,thiourea and the as-prepared Fe₃O₄ nanoparticles as starting materials,core@shell structured Fe₃O₄@MoS₂ nanocomposites was produced by hydrothermal method.Finally,we systematically studied the microstructure,electromagnetic and microwave absorption properties of Fe₃O₄@MoS₂nanocomposites.