Synthesis Of Tin Disulfide/nano-carbon Composites And Lithium Storage Properties

Lithium ion batteries?LIBs?are important extraordinary electrochemical energy storage devices for the emerging electrical vehicles and portable electronics owing to their large capacity,long life cycle and high energy density.Themainfactor affecting the performance of lithium ion batteries is the structure and composition of their electrode materials.Therefore,the study of high performance electrode materials has inevitably become the research trend.Among the electrode materials,metal sulfide has become one of the available energy storage materials due to its advantages of high capacity and low cost.Therefore,this experiment is devoted to the preparation of tin disulfide/nano-carbon anode materials with nanoscale structure by a simple low temperature stirring method using various carbon materials as the substrate.The specific contents of the study are as follows:1.The composites of N-doped CMK-3?N-CMK-3?anchored with tin disulfide?SnS₂?nanosheets?NSs?have been synthesized via a maneuverable hot bath method at low temperature.The SnS₂@N-CMK-3 composites are flake nanostructures under electron microscope.Sn S₂@N-CMK-3 composite exhibits a high initial capacity of1438.9 mAh·g^-1(200 m A·g^-1).Moreover,the electrochemical performance remained at 618.9 mAh·g^-1 after 200 cycles,which are significantly higher than that of the pristine SnS₂.The capacity retention rate is 90.2%.2.The composites of Single-Walled Carbon Nanohorns?SWCNHs?anchored with tin disulfide?SnS₂?nanosheets with adding variable polyvinylpyrrolidone?PVP?have been synthesized via a maneuverable hot bath method at low temperature.The results show that the electrochemical properties of the SnS₂ anode material can be greatly improved by the addition of SWCNHs and PVP.The discharge capacity of the SnS₂ and SnS₂@SWCNHs nanomaterials in the 1st cycle are 1186.4 mAh?g^-11 and1262.1 mAh?g^-1.The electrochemical performance of SnS₂@SWCNHs electrode remained at 444.1 mAh?g^-1 at a constant current density of 200 mA g^-11 after 100cycles,which are significantly higher than that of the SnS₂(84.5 mAh?g^-1).3.A tin disulfide/N-doped multiwalled carbon nanotube?SnS₂@N-MWCNTs?composite was synthesized by low temperature stirring method using multiwalled carbon nanotubes?N-MWCNTs?as matrix,stannous chloride and thioacetamide as reactants.The microstructure and electrochemical properties of the composite were also studied.Scanning electron microscopy?SEM?showed that the SnS₂@N-MWCNTs composite was composed of a large number of uniformly distributed nanosheets.The electrochemical performance test results show that:SnS₂@N-MWCNTs composite exhibits a high initial capacity of 1892.2 m Ah·g^-11 at a current density of 200 m A·g^-1.Moreover,the electrochemical performance remained at 741.9 mAh·g^-1 after 50 cycles,which are much higher than that of the pristine SnS₂ electrode.