碳纳米管吸附铜原子的密度泛函理论研究  

A density functional theory study of the absorption behavior of copper on single-walled carbon nanotubes

作　　者：张变霞[1,2] 杨春[1,3] 冯玉芳[1,2] 余毅[4] 

机构地区：[1]四川师范大学可视化计算与虚拟现实四川省重点实验室,成都610068 [2]四川师范大学化学与材料科学学院,成都610068 [3]电子科技大学电子薄膜与集成器件国家重点实验室,成都610054 [4]四川师范大学学报编辑部自然科学版,成都610068

出　　处：《物理学报》2009年第6期4066-4071,共6页Acta Physica Sinica

基　　金：国防预研基金(批准号:51310203;61363);四川省青年科技基金(批准号:07ZQ026-021)资助的课题~~

摘　　要：采用密度泛函方法对铜原子在有限长(5,5)椅型单壁碳纳米管的吸附行为进行了研究.计算结果表明,铜原子吸附在管外壁要比吸附在管内壁能量上更为有利,在管外壁碳原子顶位吸附最佳,属于明显的化学吸附.且用前线轨道理论对其成键特性进行了分析,表明在顶位吸附时主要由铜原子的4s轨道电子与碳纳米管中耦合的σ-π键形成新的σ键.此外还对比计算了两种典型位置电子密度,发现顶位吸附的成键中有更大的电子云重叠.进一步表明在某些情况下铜碳原子可以成键.The absorption behavior of copper atoms on the armchair （5,5） single wall carbon nanotube is investigated by the density functional theory. It is shown that the absorption on the outside nanotube is energetically preferred to that on the inside nanotube, Morever, the adsorbed copper atom on the top of carbon is more stable than that on the other outside sites. At the same time, the characteristic of the forming bond on the top of carbon between copper and SWNT is detailed. The absorption behavior belongs to chemical absorption, and based on the analysis of frontier orbital, it is shown that the new σ bond is mainly due to the interaction of 4s valence state of copper and coupling σ-π bond of SWNT. Furthermore, the calculated electron densities of two representative adsorption positions show that electron clouds overlap more on the top of carbon adsorbed copper atom, which further confirms that copper and carbon atoms can form chemical bond in a sense.

关 键 词：碳纳米管 铜原子 成键特性 

分 类 号：O481[理学—固体物理]