N-graphene motivated SnO2@SnS2 heterostructure quantum dots for high performance lithium/sodium storage
N-graphene motivated SnO2@SnS2 heterostructure quantum dots for high performance lithium/sodium storage
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N-石墨烯驱动的 SnO2@SnS2 异质结构量子点用于高性能锂/钠存储
DOI：
10.1016/j.ensm.2018.11.024
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发表时间：
2019-07-01
影响因子：
20.4
通讯作者：
Zhao, Yufeng
中科院分区：
文献类型：
--
作者：
Huang, Shifei;Wang, Miao;Zhao, Yufeng
活性材料的纳米结构工程，包括减小材料特征尺寸，或设计合适的异质结构，为改善电荷存储动力学和提高实际性能提供了巨大的希望。在本工作中，我们报道了一种新的均匀固定在N掺杂石墨烯上的SnO2@SnS2异质结构量子点(SnO2@SnS2@NG)，它是由NG和Sn4+之间的静电相互作用促进的。DFT计算分析表明，在SnO2@SnS2的异质界面上，电子传递动力学比SnO2和SnS2更快。SnO2@SnS2 HQD(3-5 nm)可以大大缩短Li/Na离子的扩散路径，而NG衬底可以提供良好的导电性和良好的结构稳定性。结果表明，这种HQDS结构的离子扩散系数是裸SnO2@SnS2纳米粒子的60倍。LiBS在0.05Ag(-1)、343 mAg(-1)、5Ag(-1)和SIBs(450 mAh g(-1)、75mAhg(-1)在5Ag-1下)都获得了高的可逆电荷存储容量。
Nanostructure engineering of the active materials including decreasing the material feature size, or designing appropriate heterostructures, offers immense promise in improving the charge storage kinetics, and enhancing the practical performance in this work, we report a new synthesis of SnO2@SnS2 heterostructured quantum dots (HQDs) uniformly anchored on N-doped graphene (SnO2@SnS2@NG), promoted by the electrostatic interaction between NG and Sn4+. The faster electron transport kinetics than SnO2 and SnS2 can be achieved at heterointerfaces of SnO2@SnS2 through DFT calculation analysis. And, the SnO2@SnS2 HQDs (3-5 nm) can shorten Li/Na ion diffusion pathway greatly, while the NG substrate can provide excellent electrical conductivity and good structural stability. As a result, the ion diffusion coefficient of this HQDs structure is 60 folds higher than that of bare SnO2@SnS2 nanoparticle. High reversible charge storage capacities are achieved for both LIBs (1081 mA h g(-1) at 0.05 A g(-1), 343 mA h g(-1) at 5 A g(-1)) and SIBs (450 mA h g(-1) at 0.05 A g(-1), 75 mAhg(-1) at 5 Ag-1).