Zhan Wenwei, Zhu Ming, Lan Jinle, Yuan Haocheng, Wang Haijun, Yang Xiaoping, Sui Gang
State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Shanghai Institute of Space Power-Sources, Shanghai 200245, China.
ACS Appl Mater Interfaces. 2020 Nov 18;12(46):51488-51498. doi: 10.1021/acsami.0c15169. Epub 2020 Nov 4.
Though being a promising anode material for sodium-ion batteries (SIBs), MoS with high theoretical capacity shows poor rate capability and rapid capacity decay, especially involving the conversion of MoS to Mo metal and NaS. Here, we report all-in-one MoS nanosheets tailored by porous nitrogen-doped graphene (N-RGO) for the first time to achieve superior structural stability and high cycling reversibility of MoS in SIBs. The all-in-one MoS nanosheets possess desirable structural characteristics by admirably rolling up all good qualities into one, including vertical alignment, an ultrathin layer, vacancy defects, and expanded layer spacing. Thus, the all-in-one MoS@N-RGO composite anode exhibits an improvement in the charge transport kinetics and availability of active materials in SIBs, resulting in outstanding cycling and rate performance. More importantly, the restricted growth of all-in-one MoS by the porous N-RGO via a strong coupling effect dramatically improves the cycling reversibility of conversion reaction. Consequently, the all-in-one MoS@N-RGO composite anode demonstrates excellent reversible capacity, outstanding rate capability, and superior cycling stability. This study strongly suggests that the all-in-one MoS@N-RGO has great potential for practical application in high-performance SIBs.
尽管具有高理论容量的MoS是一种很有前景的钠离子电池(SIBs)负极材料,但其倍率性能较差且容量衰减迅速,尤其是涉及MoS向金属Mo和NaS的转化。在此,我们首次报道了由多孔氮掺杂石墨烯(N-RGO)定制的一体化MoS纳米片,以实现MoS在SIBs中的卓越结构稳定性和高循环可逆性。一体化MoS纳米片通过将所有优良品质完美地整合在一起而具有理想的结构特征,包括垂直排列、超薄层、空位缺陷和扩大的层间距。因此,一体化MoS@N-RGO复合负极在SIBs中表现出电荷传输动力学和活性材料利用率的改善,从而带来出色的循环和倍率性能。更重要的是,多孔N-RGO通过强耦合效应限制一体化MoS的生长,极大地提高了转化反应的循环可逆性。因此,一体化MoS@N-RGO复合负极表现出优异的可逆容量、出色的倍率性能和卓越的循环稳定性。这项研究有力地表明,一体化MoS@N-RGO在高性能SIBs的实际应用中具有巨大潜力。