Graphene-scroll-sheathed α-MnS coaxial nanocables embedded in N, S Co-doped graphene foam as 3D hierarchically ordered electrodes for enhanced lithium storage
Graphene-scroll-sheathed α-MnS coaxial nanocables embedded in N, S Co-doped graphene foam as 3D hierarchically ordered electrodes for enhanced lithium storage
复制标题
嵌入 N、S 共掺杂石墨烯泡沫中的石墨烯卷轴护套 α-MnS 同轴纳米电缆作为 3D 分层有序电极，用于增强锂存储
DOI：
10.1016/j.ensm.2018.04.027
复制
发表时间：
2019-01-01
影响因子：
20.4
通讯作者：
Dou, Shixue
中科院分区：
文献类型：
--
作者：
Gao, Xu;Wang, Boya;Dou, Shixue
由于其独特的结构优势，一维（1D）纳米材料已被认为是构建用于电化学储能的多维和多功能电极配置的理想纳米级构建块。在此，通过构建N、S共掺杂3D石墨烯泡沫来设计分层过渡金属硫化物基电极配置，该泡沫具有嵌入石墨烯卷轴内的嵌入式1D超长α-MnS纳米线。这种结构工程策略依赖于通过水热辅助的自滚动和自组装过程以及硫化处理形成包含核鞘α-MnS@石墨烯卷轴的同轴纳米电缆。以同轴纳米电缆为结构单元，能够通过外部弹性石墨烯卷轴和内部空隙空间来容纳封闭的α-MnS的体积膨胀，从而保证固体电解质界面层的界面稳定。同时，具有交联3D结构的N、S共掺杂石墨烯泡沫为快速电子传输提供连续的导电路径，并且还有助于保持电极的结构和电气完整性。由于独特的结构优点，分层有序电极具有显着增强的倍率（2000 mA g（-1）下为406 mAh g（-1））和循环能力（1000 mA g（-1）下400次循环后为519 mAh g（-1））。这种分层结构设计可以提供合理的合成策略来开发耐用的过渡金属硫化物基电极。
One-dimensional (1D) nanomaterials have been recognized as ideal nanoscale building blocks to build multidimensional and multi-functional electrode configurations for electrochemical energy storage, owing to their unique structural advantages. Herein, a hierarchical transition-metal-sulfide-based electrode configuration is designed by constructing N, S co-doped 3D graphene foam with embedded 1D ultra-long alpha-MnS nanowires sheathed within graphene scrolls. This structural engineering strategy relies on forming coaxial nanocables comprising core-sheath alpha-MnS@graphene scrolls via a hydrothermally-assisted self-scrolling and self-assembly process, coupled with a sulfidation treatment. The coaxial nanocable as the structural unit is able to accommodate the volume expansion of the enclosed alpha-MnS by external elastic graphene scrolls together with internal void spaces, and thus ensures the interfacial stabilization of the solid electrolyte interphase layer. Meanwhile, N, S co-doped graphene foam with a cross-linked 3D structure offers continuous conductive paths for fast electron transfer, and also helps to maintain the structural and electrical integrity of the electrode. Because of the unique structural merits, the hierarchically ordered electrode delivers remarkably enhanced rate (406 mAh g(-1) at 2000 mA g(-1)) and cycling capability (519 mAh g(-1) after 400 cycles at 1000 mA g(-1)). Such a hierarchical structure design may present rational synthetic strategies to develop durable transition-metal-sulfide-based electrodes.