氧等离子体对碳纳米管改性的分子模拟研究  

Molecular Simulation of Carbon Nanotube Modified by Oxygen Plasma

作　　者：朱丽丽[1] 黄碧纯[1,2] 阮东亮[1] 叶代启[1,2] 

机构地区：[1]华南理工大学环境科学与工程学院,广州510006 [2]华南理工大学工业聚集区污染控制与生态修复教育部重点实验室,广州510006

出　　处：《材料导报》2012年第20期143-145,153,共4页Materials Reports

基　　金：国家自然科学基金(209077034);广东省科技计划项目(2009B050900005)

摘　　要：采用密度泛函理论研究了氧等离子体改性前后的(8,0)碳纳米管的性能,比较了改性前后结合能、能带结构及态密度之间的差异,结果表明改性后碳管的结合能变小,其表面的分散性提高,从而可以稳定存在。另外,尽管碳管的能隙Eg非常小,但其价带顶和导带底均未穿过费米能级,验证了(8,0)碳纳米管是半导体管的理论。改性后碳纳米管的几何结构受到羟基和羧基的影响很大,横截面C-C间距增大,比表面积增加;同时,羟基和羧基使得费米能Ef以及费米能级上的态密度明显增大,而且羧基的作用更显著,这表明氧等离子体增强了碳纳米管的化学活性,是一种有效的改性方法。Properties of （8,0） carbon nanotube （CNT） before and after oxygen plasma modification were stu- died using density functional theory （DFT）. The differences of CNT^s binding energy, band structure and density of states were compared. The results showed that the binding energy became smaller, suggesting that dispersion of CNT surface was enhanced and CNT could exist suitable after modification. In addition, although the Eg of （8,0） CNT was small, the top of valence band and the bottom of conduction band were not overlapping the Fermi level, which success- fully verified that （8,0） CNT was a semiconductor type. Once modified by oxygen plasma, the structure of （8,0） CNT was greatly affected by -OH and -COOH, and its specific surface area inereased. At the same time, the Ef and the density of states on the Fermi level significantly increased after modification, demonstrating that oxygen plasma strengthened CNT＇s activity and could be an effective modification method.

关 键 词：碳纳米管 密度泛函理论 氧等离子体 能带结构 态密度 

分 类 号：TB34[一般工业技术—材料科学与工程]