Synthesis,Characterization And Electrochemical Performances Of Antimony-carbon And Sulfur-carbon Nanocomposites

The combination of carbon with nanomaterials is the main method to improve the electrochemical properties of electrode materials in lithium ion and sodium ion batteries.In this paper,the antimony(Sb)/carbon composite anode material and the sulfur(S)/carbon composite cathode material were synthesized and the influence of the introduction of carbon on the electrochemical performance of the battery was also studied.The main innovations of this paper are as follows.1.We report an extensible synthesis method for scalable fabrication of antimony/carbon(Sb/NPC)composite.One-dimensional nickel(Ni-NTA)complex precursor was prepared by hydrothermal method and then annealed under Ar atmosphere to obtain the composite of metal nickel(Ni)particlesc,afterwards,and the Ni particles was replaced by SbCl3 to form a one-dimensional N-doped porous structure of Sb/carbon nanocomposite(denoted as Sb/NPC),in which the Sb nanoparticles were about 10-20 nm.When this Sb/NPC composite was used as the anode electrode material,it can deliver a reversible capacity of 556 mAh/g after at 200 mA/g after 100 cycles in Li-ion battery.In Na-ion battery,at the current of 100 mA/g,a capacity of 400.9 mAh/g can be obtained after 100 cycles.Compared with similar works reported,the electrochemical properties of the composites are improved.The improvement are mainly due to this unique nano-structure:nitrogen doping,one-dimensional,porous,nano-antimony particle,the good structural stability of the material effectively alleviates the volume expansion of Sb electrode material during the cycles.2.We report an extensible synthesis method for scalable fabrication of sufur/carbon(S/NPC-Cu)composite.Firstly,N-doped porous carbon nanosheets with uniform distribution of copper(Cu)were prepared by high temperature pyrolysis of the mixtur eof ethylene diamine tetraacetic acid(EDTA),melamine(carbon source and nitrogen source)and copper nitrate(metal source),afterwards,the S/NPC-Cu and S/NPC nanocomposites were prepared by vacuum heating heatment with sulfur.The cathode materials were invested at 0.5 C(1 C)= 1675 mAh/g),it deliver a capacity is 701 mAh/g and 588 mAh/g,respectively.Compared with the pure sulfur cathode material,the battery cycle performance of the composite electrode is greatly improved.The improvement of the battery performance should be attributed to:Nitrogen doping improves the electrical conductivity of the material and the adsorption of poly sulfides.What's more,metal sulfides further provide more active sites for polysulfide adsorption.