Core–Shell C@Sb Nanoparticles as a Nucleation Layer for High-Performance Sodium Metal Anodes
Core–Shell C@Sb Nanoparticles as a Nucleation Layer for High-Performance Sodium Metal Anodes
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核壳 C@Sb 纳米粒子作为高性能钠金属阳极的成核层
DOI：
10.1021/acs.nanolett.0c01257
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发表时间：
2020
期刊：
影响因子：
10.8
通讯作者：
Chao Wu
中科院分区：
文献类型：
--
作者：
Guanyao Wang;Ying Zhang;Bingkun Guo;Liang Tang;Gang Xu;Yuanjun Zhang;Minghong Wu;Hua-Kun Liu;Shi-Xue Dou;Chao Wu
钠金属阳极（SMA）因其低成本和天然丰富而成为下一代可充电电池技术最受青睐的选择之一。然而，枝晶生长和不稳定固体电解质界面形成导致的可逆性差，严重阻碍了SMA的实际应用。在此，我们报道了由精心设计的核壳C@Sb纳米颗粒（NP）组成的成核缓冲层能够实现钠金属的均匀电化学沉积，从而实现长期循环。这些C@Sb NPs可以通过Sb-Na合金核增加初始钠成核的活性位点，并通过碳壳保持这些核的稳定。具有该成核层的组装电池可以在 4 mA h cm-2 的高面积容量下连续重复近 6000 小时的钠电镀/剥离循环，平均库仑效率为 99.7%。这种合金基成核剂的巧妙结构设计为稳定具有目标性能的钠金属开辟了一条有前途的途径。
Sodium metal anode (SMA) is one of the most favored choices for the next-generation rechargeable battery technologies owing to its low cost and natural abundance. However, the poor reversibility resulted from dendrite growth and formation of unstable solid electrolyte interphase has significantly hindered the practical application of SMAs. Herein, we report that a nucleation buffer layer comprising elaborately designed core–shell C@Sb nanoparticles (NPs) enables the homogeneous electrochemical deposition of sodium metal for long-term cycling. These C@Sb NPs can increase active sites for initial sodium nucleation through Sb–Na alloy cores and keep these cores stable through carbon shells. The assembled cells with this nucleation layer can deliver continuously repeated sodium plating/stripping cycles for nearly 6000 h at a high areal capacity of 4 mA h cm–2with an average Coulombic efficiency 99.7%. This ingenious structure design of alloy-based nucleation agent opens up a promising avenue to stabilize sodium metal with targeted properties.