Highly Connected Silicon-Copper Alloy Mixture Nanotubes as High-Rate and Durable Anode Materials for Lithium-Ion Batteries
Highly Connected Silicon-Copper Alloy Mixture Nanotubes as High-Rate and Durable Anode Materials for Lithium-Ion Batteries
复制标题
DOI：
10.1002/adfm.201504014
复制
发表时间：
2016-01-26
影响因子：
19
通讯作者：
Chen, Kunji
中科院分区：
文献类型：
--
作者：
Song, Hucheng;Wang, Hong Xiang;Chen, Kunji
寻求高容量、高倍率和耐用的锂离子电池（LIB）阳极材料一直是促进电动汽车和其他便携式电子产品使用的一个重要方面。在这里，一种新的合金形成的方法来转换非晶Si（a-Si）包覆氧化铜（CuO）的核壳纳米线（NW）到中空和高度互连的Si-Cu合金（混合物）纳米管的报告。在简单的H-2退火后，CuO核被还原并扩散出来与a-Si壳形成合金，产生高度互连的中空Si-Cu合金纳米管，其可以用作具有坚固机械支撑的高容量和自导电阳极结构。在3.4 A g（-1）（或20 A g（-1））下循环1000次后，达到了1010 mAh g（-1）（或780 mAh g（-1））的高比容量，容量留存率约为84%（约88%），无需使用任何粘合剂或导电剂。值得注意的是，它们可以在70 A g（-1）的极快充电速率下运行35次（相当于30 s内的一个完整循环），并恢复88%的容量。这种新型的合金纳米管结构可以代表一个理想的候选人，以实现真正的潜力，硅负载锂离子电池的应用。
Seeking high-capacity, high-rate, and durable anode materials for lithium-ion batteries (LIBs) has been a crucial aspect to promote the use of electric vehicles and other portable electronics. Here, a novel alloy-forming approach to convert amorphous Si (a-Si)-coated copper oxide (CuO) core-shell nanowires (NWs) into hollow and highly interconnected Si-Cu alloy (mixture) nanotubes is reported. Upon a simple H-2 annealing, the CuO cores are reduced and diffused out to alloy with the a-Si shell, producing highly interconnected hollow Si-Cu alloy nanotubes, which can serve as high-capacity and self-conductive anode structures with robust mechanical support. A high specific capacity of 1010 mAh g(-1) (or 780 mAh g(-1)) has been achieved after 1000 cycles at 3.4 A g(-1) (or 20 A g(-1)), with a capacity retention rate of approximate to 84% (approximate to 88%), without the use of any binder or conductive agent. Remarkably, they can survive an extremely fast charging rate at 70 A g(-1) for 35 runs (corresponding to one full cycle in 30 s) and recover 88% capacity. This novel alloy-nanotube structure could represent an ideal candidate to fulfill the true potential of Si-loaded LIB applications.