Morphology-controlled Synthesis And Electrochemical Properties Research Of Hollow Micro-/nanostructures Transition Metal (Co,Mo) Sulfides

Metal composite sulfide hollow nanostructures have received intensive attention as electrode materials for electrical energy storage systems due to their unique structural features and rich chemical properties. This paper has prepared hollow micro-/nanostructures transition metal （Co, Mo） sulfides battery anode materials, and mainly studies the effect of material lithium storage properties due to its structure and composition through a series of physical and chemical methods, the main results are as follows:1. An effective approach of alcoholysis is employed to prepare hierarchical CoS₂ hollow microspheres hybrid nanosheets aggregates, and amorphous carbon can be loaded on the CoS₂ nanoparticles uniformly in the solvothermal alcoholysis process, finally the hierarchical CoS₂ hollow microspheres constructed by nanosheets are synthesized. The nano-scaled characteristics of CoS₂ nanosheets embedded in the aggregates ensure the electrode having a high capacity and the fast Li-ion diffusion in the electrode. The in-situ introduction of amorphous carbon can effectively buffer the volume change of electrochemical process. Therefore, the materials exhibit outstanding electrochemical performance.The capacity of the sample can remain stable as high as 720 mA h·g-1 after 200 cycles at constant current density of 200 mA·g-1.2. A template strategy is developed to synthesize hollow silica microcubes, and hierarchical SiO2@CoS₂ hollow microcubes are synthesized through a simple alcoholysis method using silica nanoboxes as template。The hollow structure also offers a sufficient void space, which sufficiently alleviates the mechanical stress caused by volume change. Therefore, the materials exhibit outstanding electrochemical performance. The capacity of the sample can remain stable as high as 815 mA h·g-1 after 200 cycles at constant current density of 200 mA·g-1.3. Using alcoholysis method to prepare hierarchical CuS@MoS₂ hollow nanoscubes composite materials by controlling the reaction time and changing the reaction temperature, and amorphous carbon can be loaded on the MoS₂ nanoparticles uniformly in the solvothermal alcoholysis process, finally the hierarchical CuS@MoS₂@C hollow nanoscubes composite materials are synthesized. Due to Metal sulfide compound structure of the material itself, its electrochemical performance is better than the performance of the single metal sulfides.The hollow structure and unique nanosheets in the surface can shorten the length of Li-ion diffusion, which is benefit for the rate performance. Therefore, the materials exhibit outstanding electrochemical performance.The capacity of the sample can remain stable as high as 920 mA h·g-1 after 200 cycles at constant current density of 500 mA·g-1.