抗坏血酸还原氧化石墨烯制备硫-石墨烯复合物

摘要

利用环境友好的抗坏血酸常温下通过还原氧化石墨烯制备得硫-石墨烯复合材料,用于锂硫电池正极材料.用XRD、FESEM和电化学测试对复合材料进行结构、形貌和电化学性能分析.结果表明:抗坏血酸成功地还原出石墨烯.将不同抗坏血酸用量制备的复合物装配成扣式电池,当氧化石墨烯(GO)与抗坏血酸的质量比为1∶10时,性能较好,在0.2 mA/cm2电流密度下,1.5～3V区间充放电,首次放电比容量为1 250.19 mAh/g,循环20次保持在1 216.76mAh/g,容量保持率为97.33％.%S-Graphene composites for cathode of lithium-sulfur battery were synthesized by reducing oxidized graphene with environment-friendly ascorbic acid in normal temperature.The structure,morphology and electrochemical performance of composite material were analyzed by XRD,FESEM and electrochemical tests.The results show that ascorbic acid is successful in reducing oxidized graphene.The button cell assembled with composite material in the different amount of ascorbic acid has better performance when the mass ratio of GO to ascorbic acid is 10:1.When charging-discharging in 1.5-3.0 V with the current of 0.2 mA/cm2,its initial discharge specific capacity is 1 250.19 mAh/g.The discharge specific capacity is 1 216.76 mAh/g and the capacity retention ratio is 97.33％ after 20 cycles.