钠离子电池负极材料 SbSn/石墨烯复合物的合成及电化学性能测试

Synthesis and electrochemical performance of SbSn/Graphene composites for anode materials of sodium ion battery

通过化学共沉淀法制备SnSb纳米合金,并以此为主体材料表面包覆石墨烯的核壳结构复合材料SbSn/rGO用作钠离子电池负极材料。通过XRD、SEM、EDS测试分析材料的物相结构与形貌,通过循环伏安、恒流充放电测试分析材料的电化学性能。研究表明,SbSn/rGO复合材料缓解了SnSb纳米合金团聚和体积膨胀效应,增强了材料的循环稳定性和倍率性能。SbSn/rGO复合材料150 mA·g^(-1)电流密度及0～3 V充放电电压测试,首次充放电容量为650、700 mA·h·g^(-1),第50次循环的放电比容量保持在350 mA·h·g^(-1),大幅度提高钠电负极材料比容量和循环稳定性。

The composite material SnSb nano-alloy coated with graphene core-shell structure is prepared by chemical co-precipitation method, which is used as the anode material of sodium ion battery. By the cyclic voltammetry and constant current charge and discharge tests, it shows the first charge and discharge capacity of SbSn/rGO composites are 650 mA·h·g^-1, 700 mA·h·g-1, and the discharge specific capacity of the 50th cycle is maintained at 350 mA·h·g^-1(the test current is 150 mA·g^-1 and voltage is 0~3 V). The SbSn/rGO composites could alleviate the agglomeration and volume expansion effects of SnSb nano-alloys and enhance the cycle stability and rate performance of the anode materials.