Nitrogen-Doped Multiwall Carbon Nanotubes for Lithium Storage with Extremely High Capacity
Nitrogen-Doped Multiwall Carbon Nanotubes for Lithium Storage with Extremely High Capacity
复制标题
DOI：
10.1021/nl3000908
复制
发表时间：
2012-05-01
期刊：
影响因子：
10.8
通讯作者：
Choi, Jang Wook
中科院分区：
文献类型：
--
作者：
Shin, Weon Ho;Jeong, Hyung Mo;Choi, Jang Wook
对高性能储能系统日益增长的需求催生了一类新型器件，即所谓的锂离子电容器（LICs）。顾名思义，LIC是锂离子电池和超级电容器之间的一种中间系统，旨在利用这两种储能系统的优势。在此，为了提高与其他现有碳纳米材料相比的锂存储能力，我们通过氮掺杂开发了外在缺陷的多壁碳纳米管。氮掺杂碳纳米管含有壁缺陷，锂离子可通过这些缺陷扩散，从而占据壁间空间的大部分作为存储区域。此外，当与3纳米氧化镍纳米粒子结合以进一步提高容量时，氮掺杂通过引发异常的电化学现象，如纳米粒子分裂成更小的粒子、它们在氮掺杂位点之间无团聚扩散以及容量随循环增加，实现了前所未有的电池性能。最终的电池表现出高达3500毫安时/克的容量、大于10000次的循环寿命以及1.5分钟的放电倍率能力，同时保持350毫安时/克的容量。
The increasing demands on high performance energy storage systems have raised a new class of devices, so-called lithium ion capacitors (LICs). As its name says, LIC is an intermediate system between lithium ion batteries and supercapacitors, designed for taking advantages of both types of energy storage systems. Herein, as a quest to improve the Li storage capability compared to that of other existing carbon nanomaterials, we have developed extrinsically defective multiwall carbon nanotubes by nitrogen-doping. Nitrogen-doped carbon nanotubes contain wall defects through which lithium ions can diffuse so as to occupy a large portion of the interwall space as storage regions. Furthermore, when integrated with 3 nm nickel oxide nanoparticles for a further capacity boost, nitrogen doping enables unprecedented cell performance by engaging anomalous electrochemical phenomena such as nanoparticles division into even smaller ones, their agglomeration-free diffusion between nitrogen-doped sites as well as capacity rise with cycles. The final cells exhibit a capacity as high as 3500 mAh/g, a cycle life of greater than 10 000 times, and a discharge rate capability of 1.5 min while retaining a capacity of 350 mAh/g.