硼原子掺杂对碳纳米管吸附Ne原子影响的第一性原理计算  

First-principle calculations for the adsorption of neon atom in carbon nanotube doped with boron atom

作　　者：温述龙 王茜[2] 潘敏[3] 闫跃阳 黄整[1] 

机构地区：[1]西南交通大学物理科学与技术学院,成都610031 [2]中国工程物理研究院核物理与化学研究所,绵阳621900 [3]西南交通大学超导与新能源研究开发中心,成都610031

出　　处：《原子与分子物理学报》2015年第2期241-246,共6页Journal of Atomic and Molecular Physics

基　　金：中央高校基本科研业务费资助项目(swjtu12cx019)

摘　　要：采用基于第一性原理的密度泛函理论(DFT)和局域密度近似(LDA)方法,优化计算得到碳纳米管(CNT),硼原子取代碳原子及其吸附氖原子前后系统的几何结构,能量,电子能带和态密度.结果显示,碳纳米管的能带结构与石墨的层状几何结构相似,能量的变化只在kz=0和kz=0.5平面之间沿着c轴方向出现.B原子取代C原子使价带和导带分别分裂为两个和三个能带.对Ne原子的吸附使价带能量沿着c轴方向升高并导致Fermi面附近的态密度下降.Ne原子的吸附在谷位H最稳定,顶位A其次.C-C间σ键的弯曲使Ne原子吸附在桥位b1比桥位b2处更为稳定.Ne原子在管外的吸附均为放热过程,而管内则为吸热过程.结构分析表明Ne原子对C原子有排斥作用,对B原子却具有吸引作用.B原子取代C原子的位置略凸出于CNT的管壁之外,使Ne原子的吸附能增加.Based on density functional theory （DFT） and local density approximation （LDA） methods, the ge-ometries, the energies, electronic bands and density of states are optimized and calculated for the adsorption of neon atoms on carbon nanotubes （CNT） doped with boron atoms.The results show that the energy bands of CNT have a topology similar to the layered geometry of graphite .The energy changes of the bands between the two planes of kz=0 and kz=0.5 occur only along the c-axis direction.The substituting boron atom splits the va-lence and conduction bands into two and three energy bands , respectively .The adsorption of neon atom makes the energy of the valence band rise along the c -axis direction , and the density of states near the Fermi surface decreases .The valley site H is the most stable site for the adsorption of neon atom , and the top site A is the sec-ond .The bending of the carbonic σbond along the circumferential direction makes the bridge site b 1 more stable for the adsorption of neon than the bridge site b 2 .All the adsorptions of neon atoms outside of the CNT are exo-thermic;however that inside the tube endothermic .The analysis shows the repulsion of the neon on carbon atoms and the attraction to the boron atom .Protruding slightly beyond the wall of the CNT , the substituting boron atom makes the adsorption exothermic energy of neon atom increase .

关 键 词：碳纳米管 硼掺杂 Ne原子吸附 

分 类 号：O485[理学—固体物理]