FeS/SnS@rGO负极材料的制备及其电化学性能

Preparation and Electrochemical Properties of FeS/SnS@rGO Anode Material

过渡金属硫化物具有良好的储锂性能,比容量高,有望成为锂离子电池的负极材料;缺点则是导电能力差,充放电过程中容易发生结构坍塌或体积膨胀,导致比容量下降较快,循环充放电性能差。针对此缺陷,本文将氯化铁、氯化锡、硫代乙酸铵、还原氧化石墨烯(rGO)等组分在乙醇溶剂中充分混合后,采用溶剂热反应-高温热解法制备得到了氮掺杂、rGO包覆的复合材料FeS/SnS@N-rGO。在该材料中,FeS/SnS颗粒被片状rGO包裹形成三明治结构。作为锂离子电池的负极材料时,在0.1A·g^(-1)的电流密度下,首次充/放电比容量达到818.6/1430.0mAh·g^(-1),经过100次循环后,放电比容量为594.5mAh·g^(-1),在不同的倍率下充放电时,能保持较高的比容量和结构稳定性。

Transition metal sulfides was expected to be the anode material for lithium-ion batteries due to their good lithium storage properties and high specific capacity,but suffer from poor conductivity,structure collapse,volume expansion,capacity decline and bad cyclic charge/discharge performance.To overcome these defects,N-doped RGo-coated composite FeS/SnS@N-rGO was prepared by solvent-thermal reaction combined with high temperature pyrolysis using ferric chloride,tin chloride,ammonium thioacetate and reduced graphene oxide(rGO)as raw materials.The as-prepared composite had a a sandwich structure,in which,the sheet rGO coated on FeS/SnS particle size.As an anode material for lithium-ion batteries,the FeS/SnS@N-rGO delivered an initial charge/discharge specific capacity of 818.6/1430.0 mAh/g at current density of 0.1A/g,and remained at 594.5 mAh/g after 100 cycles.When charge and discharge was performed at different rates,it could maintain a higher specific capacity and structural stability.