空位缺陷对zigzag型石墨烯纳米带电子结构的影响

徐慧^{1, 2}，张丹¹，陈灵娜²

(1. 中南大学 物理与电子学院，湖南 长沙，410083；
2. 中南大学 材料科学与工程学院，湖南 长沙，410083)

摘 要：为了了解空位缺陷对zigzag型石墨烯纳米带电子结构的影响，采用基于密度泛函理论的第一性原理，计算含不同空位碳原子数的缺陷zigzag型石墨烯纳米带的电子结构。研究结果表明：含缺陷的zigzag型石墨烯纳米带都呈现出类金属性的电子结构特征，其电子结构与缺失碳原子的含量及缺陷位置附近碳原子的饱和度密切相关；缺陷的存在会引入缺陷能级，当缺失的碳原子数为奇数时，费米面附近存在3条能级；当缺失的碳原子数为偶数时，费米面附近只有2条能级；随着空位缺陷的增加，缺陷处碳原子的不饱和度也增加，从而费米能附近的态密度峰出现相应衰减。

关键词：zigzag石墨烯纳米带；空位缺陷；电子结构

Effect of defect on electronic properties of zigzag graphene nanoribbons

XU Hui^{1, 2}, ZHANG Dan¹, CHEN Ling-na²

(1. School of Physical and Electronic, Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China)

Abstract:Using the ab initio density-functional theory method, the electronic structures of zigzag graphene nanoribbons(ZGNRs) with different numbers of carbon defects were calculated. The results show that all of the defected structures are quasi-metallicity, and the electronic structure characteristics depend on the number of the defected carbons and unsaturated degree of defect position in ZGNRs. The defected bands can be introduced by the states of defects and also there are three energy bands close to Feimi level when the number of defected carbons is odd, otherwise there are only two energy bands for even. With the increase of the number of defected carbons, the peaks of density of states near Fermi level decrease.

Key words:zigzag graphene nanoribbons; vacancy defects; electronic properties