Self-Assembly-Induced Alternately Stacked Single-Layer MoS2 and N-doped Graphene: A Novel van der Waals Heterostructure for Lithium-Ion Batteries

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• 作者：Chenyang Zhao ; Xu Wang ; Junhua Kong ; Jia Ming Ang ; Pooi See Lee ; Zhaolin Liu ; Xuehong Lu
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2016
• 出版时间：January 27, 2016
• 年：2016
• 卷：8
• 期：3
• 页码：2372-2379
• 全文大小：525K
• ISSN：1944-8252

文摘

In this article, a simple self-assembly strategy for fabricating van der Waals heterostructures from isolated two-dimensional atomic crystals is presented. Specifically, dopamine (DOPA), an excellent self-assembly agent and carbon precursor, was adsorbed on exfoliated MoS₂ monolayers through electrostatic interaction, and the surface-modified monolayers self-assembled spontaneously into DOPA-intercalated MoS₂. The subsequent in situ conversion of DOPA to highly conductive nitrogen-doped graphene (NDG) in the interlayer space of MoS₂ led to the formation of a novel NDG/MoS₂ nanocomposite with well-defined alternating structure. The NDG/MoS₂ was then studied as an anode for lithium-ion batteries (LIBs). The results show that alternating arrangement of NDG and MoS₂ triggers synergistic effect between the two components. The kinetics and cycle life of the anode are greatly improved due to the enhanced electron and Li⁺ transport as well as the effective immobilization of soluble polysulfide by NDG. A reversible capacity of more than 460 mAh/g could be delivered even at 5 A/g. Moreover, the abundant voids created at the MoS₂–NDG interface also accommodate the volume change during cycling and provide additional active sites for Li⁺ storage. These endow the NDG/MoS₂ heterostructure with low charge-transfer resistance, high sulfur reservation, and structural robustness, rendering it an advanced anode material for LIBs.