Research On Iron-based And Ti-based Materials As Anode Materials For Sodium-ion Batteries

Among a variety of batteries,lithium ion batteries（LIBs）with a superior performance are often viewed as energy storage device.However,limited resource and high price of lithium salts restrict its application.Lithium and sodium belong to the same group of elements,have a lot of similar nature and even can be substituted in many ways.And sodium has the advantage of abundant in the earth,has higher than lithium REDOX potential,in terms of price,environmental protection and safety has more advantages.The performance of the anode materials is one of the important elements that affect sodium ion battery performance.Iron base material because of reactants,the cost is low,in the field of sodium ion battery has a big advantage.NASICON material NaTi₂（PO₄）₃ as intangible variable,and higher potential therefore has an obvious advantage in security.This thesis first step by hydrothermal method,with simple process synthesized by a new type of iron-based FeCO3 sodium ion battery cathode materials.After the test,the material has excellent capacity.Under current density of 50 mAg^-1,the charging capacity of first cycle is 333.8 mAhg^-1,and after stability,there is still has a capacity of more than 150 mAhg^-1.Through in-situ coated monolayer graphene,the capacity and stability of the FeCO₃ is effectively enhanced.Article also by changing the type of surfactant,improve the morphology of the material,the preparation of the inclined hexahedron FeCO3 materials,greatly improves the electrochemical properties of the material.Under the current density of200 mAg^-1 and 50 cycles,it still maintain the capacity of the 150 mAhg^-1.The surfactant was replaced with cationic surfactant（CTAB）,and the influence has been discussed.The Prussian blue material in which the element of Cu was added has been used as precursor.Fe₃O₄ with high capacity and electronic conductivity has been synthesis after annealed under reducing atmosphere.Finally,the article explores the temperature condition of flow disguised synthesis of NaTi₂（PO₄）₃,and the important effect of the dispersant on flow disguised method was be found.