Two-dimensional porous carbon-coated sandwich-like mesoporous SnO2/graphene/mesoporous SnO2 nanosheets towards high-rate and long cycle life lithium-ion batteries
Two-dimensional porous carbon-coated sandwich-like mesoporous SnO2/graphene/mesoporous SnO2 nanosheets towards high-rate and long cycle life lithium-ion batteries
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二维多孔碳包覆三明治状介孔SnO2/石墨烯/介孔SnO2纳米片用于高倍率和长循环寿命的锂离子电池
DOI：
10.1016/j.cej.2018.08.217
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发表时间：
2019-04-01
影响因子：
15.1
通讯作者：
Wang, Yanli
中科院分区：
文献类型：
--
作者：
Yao, Weiqi;Wu, Shengbo;Wang, Yanli
二维碳包覆介孔SnO 2/石墨烯/介孔SnO 2纳米片（C@SnO2-rGO-SnO 2）是一种新型锂离子电池负极材料。以介孔SiO2/石墨烯/介孔SiO2（SiO2-rGO-SiO2）纳米片为模板，可以有效地调控SnO 2纳米晶的尺寸。大量介孔纳米结构的存在不仅可以提供足够的缓冲空间，缓解SnO 2在充放电过程中的体积变化，还可以提供更多的表面反应位点，促进电解液向电极内部渗透，提高表面储锂容量。石墨烯作为微型集流体提供了快速的Li+扩散和传输，并且碳涂覆的保护层有效地防止了SnO 2聚集，这有助于在循环期间形成稳定的固体电解质界面（SEI）膜。此外，石墨烯和碳包覆壳的协同效应构成了优异的导电网络，克服了SnO 2电导率低的缺点。C@SnO2-rGO-SnO 2电极具有良好的可逆性（在0.2A g（-1）下300次循环后为1211 mAh g（-1）），良好的倍率性能（5 A g（-1）时为545 mAh g（-1），10 A g（-1）时为315 mAh g（-1）），以及上级的长周期稳定性（在1A g（-1）下1200次循环后703 mAh g（-1），在2A g（-1）下1200次循环后525 mAh g（-1））。
Two-dimensional (2D) carbon-coated sandwich-like mesoporous SnO2/graphene/mesoporous SnO2 nanosheets (C@SnO2-rGO-SnO2) is conceived and synthesized as a novel anode material towards advanced lithium-ion battery. The nanocrystals size of SnO2 could efficiently manipulate using sandwich-like mesoporous SiO2/graphene/ mesoporous SiO2 (SiO2-rGO-SiO2) nanosheets as template. The existence large quantity of mesoporous nanostructure not only could provide sufficient buffer space for alleviating volume change of SnO2 during the discharge/charge process, but also supply more surface reaction sites for facilitating the penetration of electrolyte into electrode and enhancing surface lithium storage capacity. The graphene acts as mini-current collector provides rapid Li+ diffusion and transportation, and the carbon-coated protection layer prevents SnO2 aggregation effectively, which contributes to form stable solid electrolyte interface (SEI) film during cycling. Furthermore, the synergistic effect of graphene and carbon-coated shell constitutes excellent conductive network, which overcomes low electrical conductivity shortage of SnO2. The C@SnO2-rGO-SnO2 electrode exhibits excellent reversibility (1211 mAh g(-1) after 300 cycles at 0.2 A g(-1)), good rate capability (545 mAh g(-1) at 5 A g(-1), 315 mAh g(-1) at 10 A g(-1)) and superior long-cycle stability (703 mAh g(-1) after 1200 cycles at 1 A g(-1), 525 mAh g(-1) after 1200 cycles at 2 A g(-1)).