Energetics of lithium ion adsorption on defective carbon nanotubes
Energetics of lithium ion adsorption on defective carbon nanotubes
复制标题
DOI：
10.1103/physrevb.71.245418
复制
发表时间：
2005-06-01
影响因子：
3.7
通讯作者：
Hasegawa, M
中科院分区：
文献类型：
--
作者：
Nishidate, K;Hasegawa, M
采用密度泛函理论研究了锂离子在单壁碳纳米管上的吸附热力学。我们使用局域密度近似（LDA）和广义梯度近似（GGA）的交换相关能量泛函。LDA和GGA计算表明，锂在原始和有缺陷的（8，0）单壁碳纳米管上的吸附过程相对于金属锂是放热的。另一方面，锂在（5，5）单壁碳纳米管上的吸附可以是吸热的，这取决于缺陷结构。当表面上的缺陷环变大时，锂通过环扩散的能垒降低，并且能垒的峰值位置向单壁碳纳米管的中心移动。分子动力学模拟也被用来研究锂通过侧壁上的缺陷环进入单壁碳纳米管的扩散动力学。这些结果表明，在具有大缺陷环的单壁碳纳米管内部积累锂离子的可能性。
We apply the density-functional theory to study energetics of lithium ion adsorption on single-wall carbon nanotubes (SWNTs). We use both the local-density approximation (LDA) and the generalized-gradient approximation (GGA) for the exchange-correlation energy functional. Both the LDA and GGA calculations indicate that adsorption processes of lithium onto the pristine and defective (8,0) SWNT are exothermic with respect to the metallic lithium. On the other hand, the lithium adsorption on the (5,5) SWNT can be endothermic depending on the defect structures. As the defective ring on the surface becomes large, the energy barrier for lithium diffusion through the ring lowers and the peak position of the barrier shifts toward the center of the SWNT. Molecular dynamics simulations are also performed to study the diffusion dynamics of the lithium into the SWNT through the defective rings on the sidewall. These results suggest the possibility of accumulating lithium ions inside the SWNT with large defective rings.