An Advanced MoS2/Carbon Anode for High-Performance Sodium-Ion Batteries
An Advanced MoS2/Carbon Anode for High-Performance Sodium-Ion Batteries
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DOI：
10.1002/smll.201401521
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发表时间：
2015-01-27
期刊：
影响因子：
13.3
通讯作者：
Wang, Chunsheng
中科院分区：
文献类型：
--
作者：
Wang, Jingjing;Luo, Chao;Wang, Chunsheng
二硫化钼（MoS 2）具有高比容量、丰富的资源和低成本等优点，是一种很有前途的高性能钠离子电池负极材料。然而，循环稳定性差，倍率性能低，电化学反应机理不清楚是MoS 2负极在钠离子电池中的主要挑战。在这项研究中，二硫化钼/碳（MoS 2/C）纳米球的制造和用于钠离子电池阳极。MoS 2/C纳米球在0.1C下提供520 mAh g（-1）的可逆容量，并且在1C的高电流密度下保持在400 mAh g（-1）持续300次循环，证明了迄今为止用于Na离子电池的MoS 2的最佳循环性能。高容量归因于短的离子和电子扩散路径，这使得能够实现快速的电荷转移和低浓度极化。循环性能稳定，库仑效率高（接近100%）的MoS 2/C纳米球归因于（1）如通过非原位X射线衍射（XRD）证明的在钠化/去钠化期间MoS 2的高度可逆的转化反应和（2）在氟代碳酸亚乙酯（FEC）中形成稳定的固体电解质界面（SEI）层。基于电解质，如通过傅立叶变换红外光谱（FTIR）测量所证明的。
Molybdenum disulfide (MoS2) is a promising anode for high performance sodium-ion batteries due to high specific capacity, abundance, and low cost. However, poor cycling stability, low rate capability and unclear electrochemical reaction mechanism are the main challenges for MoS2 anode in Na-ion batteries. In this study, molybdenum disulfide/carbon (MoS2/C) nanospheres are fabricated and used for Na-ion battery anodes. MoS2/C nanospheres deliver a reversible capacity of 520 mAh g(-1) at 0.1 C and maintain at 400 mAh g(-1) for 300 cycles at a high current density of 1 C, demonstrating the best cycling performance of MoS2 for Na-ion batteries to date. The high capacity is attributed to the short ion and electron diffusion pathway, which enables fast charge transfer and low concentration polarization. The stable cycling performance and high coulombic efficiency (approximate to 100%) of MoS2/C nanospheres are ascribed to (1) highly reversible conversion reaction of MoS2 during sodiation/desodiation as evidenced by ex-situ X-ray diffraction (XRD) and (2) the formation of a stable solid electrolyte interface (SEI) layer in fluoroethylene carbonate (FEC) based electrolyte as demonstrated by fourier transform infrared spectroscopy (FTIR) measurements.