掺杂碳纳米管对五氯酚吸附作用的理论研究

Theoretical study on the adsorption interaction of the pristine and doped carbon nanotubes towards pentachlorophenol

为了寻找检测高毒性、持久性有机污染物五氯酚(PCP)的新型材料,应用密度泛函理论研究了(8,0)和(5,5)单壁碳纳米管(SWCNT)以及相应的Si、B和N掺杂的SWCNT对PCP分子的吸附性能.计算结果表明,(8,0)和(5,5)SWCNT与PCP分子之间为物理吸附;Si原子掺杂(8,0)和(5,5)SWCNT,引起了碳纳米管掺杂部位六元环的畸变,增强了SWCNT的反应活性,掺杂后的SWCNT对PCP分子形成化学吸附,其几何结构和电子性质发生了显著变化;B和N原子掺杂的SWCNT对PCP分子的吸附没有明显增强.Si原子掺杂的SWCNT最有潜力用于检测PCP分子.

In order to explore the novel materials to detect high toxic persistent organic pollutant pentachlorophenol （PCP）, we investigate the adsorption properties of the pristine （8,0） and （5,5） single-walled carbon nanotubes （SWCNTs） as well as Si-, B-,and N-atom doped （8,0） and （5,5） SWCNTs towards the PCP molecule by performing density functional theory calculations. The calculated results show the pristine （8,0） and （5,5） SWCNTs present the physisorption to PCP molecule. As a Si atom is doped into （8,0） and （5,5） SWCNTs, the six-membered ring near the doping site of the SWCNTs are deformed importantly, making the SWCNTs very active towards the PCP molecule. The Si atom doped nanotubes present strong chemisorption to the PCP molecule, and their geometric structures and electronic properties present dramatic changes. However, B atom and N atom doping into SWCNTs can＇t improve their adsorption capability to PCP molecule. So the Si-doped BNNT is expected to be a potential resource for detecting toxic PCP molecules.