Hierarchical Sulfur-doped Graphene Foam Embedded with Sn Nanoparticles for Superior Lithium Storage in LiFSI-based Electrolyte.
Hierarchical Sulfur-doped Graphene Foam Embedded with Sn Nanoparticles for Superior Lithium Storage in LiFSI-based Electrolyte.
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DOI：
10.1021/acsami.9b10613
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发表时间：
2019-07
影响因子：
9.5
通讯作者：
Jian Wang;Jin Yang;Qingbo Xiao;Lujie Jia;Hongzhen Lin;Yuegang Zhang
中科院分区：
文献类型：
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作者：
Jian Wang;Jin Yang;Qingbo Xiao;Lujie Jia;Hongzhen Lin;Yuegang Zhang
基于锡（Sn）负极的锂离子电池具有高能量密度和合理成本的优点。然而，它们的商业化遭受由活性材料聚集、巨大的体积变化和固体电解质界面（SEI）的连续形成/变形引起的快速容量衰减。在此，我们报道了由嵌入分级多孔硫掺杂石墨烯泡沫（Sn@3DSG）中的纳米尺寸的金属Sn颗粒制成的阳极。在这种设计中，硫掺杂的石墨烯泡沫提供了丰富的活性缺陷位点，以促进锂离子从Sn纳米颗粒外部到内部的快速扩散。同时，由石墨烯的自组装和纳米尺寸的金属Zn的蒸发产生的分级孔提供足够的空间来容纳Sn的体积变化。由于这些优点，所制备的Sn电极在基于LiFSI的电解液中表现出优异的锂化容量（在200 mA g-1下为1272 mA h g-1）和高倍率性能（在2000 mA g-1下为345 mA h g-1）。研究还发现，在LiFSI基电解液中，Sn电极表面形成了一层富含LiF-Li 3 N的SEI膜，有利于提高电极的循环稳定性。我们的工作表明，复合锡阳极的未来高能量密度的锂离子电池的巨大前景。
Lithium ion batteries based on tin (Sn) anode have the advantage of high energy density with reasonable cost. However, their commercialization suffers from rapid capacity fading caused by active material aggregation, huge volumetric change and continuous formation/deformation of solid electrolyte interphase (SEI). Herein, we report an anode made of nanosized metallic Sn particles embedded in hierarchically porous sulfur-doped graphene foam (Sn@3DSG). In this design, the sulfur-doped graphene foam renders an abundant active defect sites to facilitate rapid lithium ion diffusion from outside to inside the Sn nanoparticles. Meanwhile, the hierarchical pores resulting from the self-assembly of graphene and evaporation of nanosized metallic Zn provide sufficient spaces to hold the volumetric changes of Sn. Owing to these merits, the as-prepared Sn electrode exhibits an excellent lithiated capacity (1272 mA h g-1 at 200 mA g-1) and high-rate performance (345 mA h g-1 at 2000 mA g-1) in the LiFSI-based electrolyte. It is also discovered that a LiF-Li3N-rich SEI layer is formed on the surface of Sn electrode in LiFSI-based electrolyte, which is beneficial for enhancing the electrode's cycling stability. Our work shows great promise of the composite Sn anodes for future high-energy-density lithium ion batteries.