低温氧化-还原法制备石墨烯负极材料

Preparing graphene anode material via low temperature redox method

通过低温氧化．还原法制备了石墨烯（GNS），用透射电子显微镜（TEM）、原子力显微镜（AFM）等方法对产物进行分析。用恒流充放电测试，分析了石墨氧化时间、石墨与氧化剂的质量比及氧化石墨超声波处理时间等对GNS嵌脱锂性能的影响。在石墨氧化时间为48h，石墨与氧化剂的质量比为1．0：6．0及氧化石墨超声波处理时间为60min的条件下制得的GNS，电化学性能最好。以74mA／g的电流在0～3．5V充放电，首次嵌、脱锂比容量分别为1574．2mAh／g和910．4mAh／g，经20次循环，电池达到稳定状态，容量保持率为89％。

Graphene（GNS） was prepared via low temperature redox method. The products were analyzed by transmission electron microscope （TEM） and atomic force microscope （AFM） methods. The effects of graphite oxidation time, mass ratio of graphite and oxidant and time of ultrasonic treatment to Li intercalation/deintercalation performance of GNS were analyzed by galvanostatic charge-discharge test. When oxidation time was 48 h, mass ratio of graphite and KMnO4 was 1.0：6.0 and the time of ultrasonic treatment was 60 min, GNS synthesized under the condition had the best electrochemical performance. When charged-discharged in 0- 3.5 V with the current of 74 mA/g, its initial specific Li intercalation and deintercalation capacity was 1 574.2 mAh/g and 910.4 mAh/g, respectively, the battery was in a stable state after 20 cycles, the capacity retention was 89%.