不同链长烷烃在碳纳米管表面行为的分子动力学模拟

Molecular dynamics simulation study on the behavior of short alkanes on carbon nanotube surface

采用分子动力学方法模拟了不同长度的烷烃在单壁碳纳米管表面的吸附和取向过程,直观地给出了过程中很多微观信息,如链与纳米管管轴的夹角,链的弯曲程度等.结果表明短链烷烃能够被吸附在纳米管表面并沿着特定的方向取向;碳纳米管表面起到诱导取向的作用,并且该诱导作用对离表面最近的吸附层作用最明显;在吸附过程中,烷烃链发生弯曲,而吸附以后,取向的烷烃链倾向于采取伸直的状态。

Molecular dynamics simulations were performed to study the behavior of alkanes on single wall carbon nanotube.The evolution of global bond-orientational order parameter and average angle between alkane molecule and nanotube axis were shown.Our results show that the four kinds of alkanes are all adsorbed on the nanotube surface and orient at a certain direction except butane.Nanotube sur-face affects the nearest adsorption alkane layer obviously.Alkane molecular bend during the adsorption process and tend to be zigzag-extended conformation after that.This will enrich the information of the research and application of materials based on alkane/carbon nanotube.