摘要
基于密度泛函理论的第一性原理,研究了(5,5)型封闭碳纳米管(CNT)帽端掺杂钛原子对其场发射性能的影响。结果表明:钛原子掺杂CNT体系的几何结构更加稳定;施加电场后,掺杂CNT的态密度在费米能级处明显增加,赝能隙显著减小,电子的活跃度明显提高;钛原子掺杂不仅引起了CNT最低未占有轨道与最高占有轨道的能量差值和有效功函数的减小,而且使电子向掺杂CNT帽端聚集。说明钛原子掺杂可以显著提高CNT的场发射性能。
The influence of Ti-doping on the field emission properties of the capped（ 5,5） carbon nanotube（ CNT） was investigated with the first principle calculation on the basis of density functional theory. The calculated results indicate that Ti-doping significantly affects the geometrical and electronic structures and effectively betters the emission property of the CNT. To be specific,Ti-doping enhances the stability of the geometrical structure of the CNT,considerably increases the density of states at Fermi level in an external electric field,sharply decreases the pseudo-gap and greatly improves the electron activity. In addition,Ti-doping reduces the energy difference between the lowest unoccupied and the highest occupied orbitals,decreases the effective work function of the CNT,and increases the electron density at the apex of the Ti-doped CNT.
作者
卢子龙
安立宝
刘扬
Lu Zilong;An Libao;Liu Yang(College of Mechanical Engineering, North China University of Science and Technology, Tangshan 063210, China)
出处
《真空科学与技术学报》
CSCD
北大核心
2017年第11期1122-1127,共6页
Chinese Journal of Vacuum Science and Technology
基金
国家自然科学基金项目(51472074
51172062)
河北省百人计划资助项目(E2012100005)
关键词
碳纳米管
钛掺杂
场发射
第一性原理
Carbon nanotubes,Ti doping, Field emission, First principles
