A Beaded-String Silicon Anode
详细信息 查看全文
- 作者：Chuan-Fu Sun ; Khim Karki ; Zheng Jia ; Hongwei Liao ; Yin Zhang ; Teng Li ; Yue Qi ; John Cumings ; Gary W. Rubloff ; YuHuang Wang
- 刊名：ACS Nano
- 出版年：2013
- 出版时间：March 26, 2013
- 年：2013
- 卷：7
- 期：3
- 页码：2717-2724
- 全文大小：462K
- 年卷期：v.7,no.3(March 26, 2013)
- ISSN：1936-086X
文摘
Interfacial instability is a fundamental issue in heterostructures ranging from biomaterials to joint replacement and electronic packaging. This challenge is particularly intriguing for lithium ion battery anodes comprising silicon as the ion storage material, where ultrahigh capacity is accompanied by vast mechanical stress that threatens delamination of silicon from the current collectors at the other side of the interface. Here, we describe Si-beaded carbon nanotube (CNT) strings whose interface is controlled by chemical functionalization, producing separated amorphous Si beads threaded along mechanically robust and electrically conductive CNT. In situ transmission electron microscopy combined with atomic and continuum modeling reveal that the chemically tailored Si鈥揅 interface plays important roles in constraining the Si beads, such that they exhibit a symmetric 鈥渞adial breathing鈥?around the CNT string, remaining crack-free and electrically connected throughout lithiation鈥揹elithiation cycling. These findings provide fundamental insights in controlling nanostructured interfaces to effectively respond to demanding environments such as lithium batteries.