以天然石墨为原料,采用改进的Hummers法合成含Mn的氧化石墨;400℃条件下氢气还原制备了锰氧化物/石墨烯复合材料。利用XRD、SEM和TEM对所制备的复合材料进行了表征。结果表明锰氧化物(MnOx)颗粒均匀地分布在石墨烯片层表面。将复合材料作为锂离子电池负极进行研究,在50mA/g电流密度下,首次库伦效率为70.4%,可逆容量达876mAh/g,并且具有良好的循环性能,在30次循环后仍保持在700mAh/g以上。
The precursor of Mn hybrid material was synthesized by a modified Hummers method and MnOx/graphene composites were obtained through a reduction in nitrogen and hydrogen atmosphere at 400℃.The composite material was investigated as anode materials for lithium ion batteries via scanning and transmission electron microscopy(TEM),X-ray diffraction(XRD) and a variety of electrochemical testing techniques.Experimental results showed that nano-particles of manganese oxide were well dispersed on the surface of graphene sheets.The first reversible capacity of the prepared composite was as high as 876mAh/g at current density of 50mA/g.After 30 cycles,the reversible specific capacity was still maintain at more than 700mAh/g.