Mn_3N_2/CMK-8复合材料的制备及其作为锂离子电池负极材料的性能

Synthesis and Electrochemical Performance of Mn_3N_2/CMK-8 Nanocomposite Negative Electrode Materials for Lithium-Ion Batteries

将MnNO3填充在有序介孔碳CMK-8孔道中,然后在氨气气氛中烧结合成了Mn3N2/CMK-8复合材料。利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线衍射(XRD)对其结构和微观形貌进行了表征。利用充放电测试考察了复合材料作为锂离子电池负极材料的性能。发现Mn3N2分布在CMK-8孔道中及其周围,复合材料的充放电性能显著优于Mn3N2,复合材料中Mn3N2的比容量明显高于无CMK-8的样品(在恒电流为100mA/g时,比容量为480 mAh·g-1),循环20次的容量损失率只有0.62%。本研究结果表明CMK-8明显提高了Mn3N2的充放电性能,可能是CMK-8特殊的孔道结构和良好的导电性减小了Mn3N2的粒径并提高了其电导率。

The composite of ordered mesoporous carbon （CMK- 8 ） and Mn3 N2 （Mns N2/CMK -8 ） was prepared by the wet impregnation of CMK - 8 with MnNO3 solution followed by calcination. Its morphology and structure were examined u- sing scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and X -ray diffraction （XRD）. Its electrochemical performance as the negative electrode material of lithium - ion batteries was investigated by galvanostatic charge -discharge tests. The results show that Mn3N2 is formed inside the mesopore channels of CMK- 8 and some particles are located on the surface of CMK-8, The composite shows significantly greater high -rate performance than c Mn3 N2. The specific capacity of Mn3 N2 in the composite is higher than Mn3 N2 without CMK - 8 （480 mAh · g- 1 ）. The capac- ity loss after 20 cycles was less than 0.62%. This result clearly indicates that CMK - 8 improves the high rate performance of Mn3N2, likely by reducing the particle size of MnaN2 and increasing its electronic conductivity owing to the unique struc-ture and good electronic conduction nature of CMK - 8.