Preparation And Electrochemical Performance Research Of MoS₂\RGO\TiO₂ Composite Anode Material

With the rapid development of electric vehicles and mobile electronic devices,graphite,as commercial anode material of lithium battery,can not meet the development demand of market,due to its low specific capacity and safety problem.Therefore,it is urgent to find a new anode material instead of graphite.MoS2 is considered as the new generation commercial anode material for lithium battery because of its high energy storage density,unique layered structure and high safety.However,the large volume expansion upon cycling and the poor conductivity,which seriously affect its cycle stability and high rate performance.In view of the above disadvantages,in this paper,TiO2 nanowire arrays and reduced graphene oxide are used to improve their stability and enhance their electrical conductivity,respectively.So the cycle stability and rate performance of MoS2 are improved effectively.The detail contents of this paper are shown as follows:(1)The electrochemical properties of skeleton TiO2 nano wire arrays supported MoS2 nanosheets.First,the stable TiO2 nanowire arrays with a diameter of 40-80 nm were prepared by hydrothermal method and then coated with MoS2 nanosheets by another hydrothermal.The morphology and electrochemical analysis show that when MoS2 nanosheets uniformly coat TiO2 nanowire arrays,the composite exhibits bettter cycle stability(502 mA h g-1 after 100 cycles at 100 mA g-1 and 301 mA h g-1 after 250 cycles at 1000 mA g-1).(2)The electrochemical properties of reduced graphene oxide composited MoS2 nanosheets.First,the graphene oxide was prepared by a modified Hummers method,and then MoS2 nanosheets were prepared by hydrothermal methods.The morphology tests show that the MoS2 nanosheets were evenly dispersed on reduced graphene oxide which fabricated by microwave hydrothermal.The electrochemical performance of the composite is obviously improved compared to the pure MoS2 nanosheets.The composite fabricated by microwave hydrothermal exhibits better high rate performance,after 500 cycles at 1000 mA/g,the reversible capacity is 446 mAh/g.(3)The electrochemical properties of reduced graphene oxide composited TiO2 nanowire arrays supported MoS2 nanosheets.The reduced graphene oxide/MoS2 nanosheets were prepared on the TiO2 nanowire arrays by hydrothermal method,and then annealed at different temperatures.When the composite is annealed at 300 ? and 400 ?,structure is more complete without fracture trace.The composite annealed at 400 ? shows high reversible capacity,excellent cycle stability and eminent high rate performance,the discharge specific capacity retention is 680 mA h/g at 200 mA/g after 100 cycles and 532 mA h/g at 1000 mA/g after 600 cycles.