物理化学学报 >> 2013, Vol. 29 >> Issue (08): 1648-1654.doi: 10.3866/PKU.WHXB201305211

理论与计算化学 上一篇    下一篇

扶手椅型二硫化钼纳米带的电子结构与边缘修饰

杨志雄1, 杨金新1, 刘琦1, 谢禹鑫1, 熊翔2, 欧阳方平1,2   

  1. 1 中南大学物理与电子学院, 长沙 410083;
    2 中南大学粉末冶金研究院, 粉末冶金国家重点实验室, 长沙 410083
  • 收稿日期:2013-01-02 修回日期:2013-05-21 发布日期:2013-07-09
  • 通讯作者: 欧阳方平 E-mail:oyfp04@mails.tsinghua.edu.cn
  • 基金资助:

    国家自然科学基金(51272291), 湖南省自然科学基金(11JJ4001), 中国博士后科学基金(2012M511399), 湖南省科技计划( 2012RS4009)和中南大学博士后科学基金(201202025)资助项目

Electronic Structure and Edge Modification of Armchair MoS2 Nanoribbons

YANG Zhi-Xiong1, YANG Jin-Xin1, LIU Qi1, XIE Yu-Xing1, XIONG Xiang2, OUYANG Fang-Ping1,2   

  1. 1 School of Physics and Electronics, Central South University, Changsha 410083, P. R. China;
    2 Powder Metallurgy Research Institute, and State Key Laboratory of Powder Metallurgy, Changsha 410083, P. R. China
  • Received:2013-01-02 Revised:2013-05-21 Published:2013-07-09
  • Contact: OUYANG Fang-Ping E-mail:oyfp04@mails.tsinghua.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (51272291), Natural Science Foundation of Hunan Province, China (11JJ4001), China Postdoctoral Science Foundation (2012M511399), Science and Technology Program of Hunan Province, China (2012RS4009), and Postdoctoral Seience Foundation of Central South University, China (201202025).

摘要:

采用基于密度泛函理论的第一性原理计算方法, 研究了扶手椅型二硫化钼纳米带的几何构型与电子结构, 发现其稳定性与电子性质敏感地依赖于边缘修饰. 随着边缘修饰的H原子数增加, 纳米带变得更加稳定, 并在间接带隙半导体、半金属和直接带隙半导体之间转变. 纳米带的能带结构和电子态密度显示, 其费米能级附近的能带主要由边缘态贡献. 当二硫化钼纳米带两边用不同数目的H原子修饰时, 纳米带同时具有由这两种修饰引起的边缘态并且两种边缘态的相互影响很小. 研究了三类纳米带带隙与宽度的关系, 对于每个原胞修饰0个或8个H原子的纳米带, 带隙随宽度以3为周期振荡变化; 而对于每个原胞修饰4个H原子的纳米带, 带隙振荡不再具有周期并且振荡幅度变小.

关键词: 二硫化钼, 纳米带, 悬挂键, 边缘态, 第一性原理, 电子结构

Abstract:

The geometries and electronic properties of armchair MoS2 nanoribbons were investigated by the first-principles method based on density functional theory. It was found that the stability and electronic properties of armchair MoS2 nanoribbons sensitively depend on edge modification. Increasing the number of hydrogen atoms on the edge caused the nanoribbons to become more stable and transition between indirect-gap semiconductor, semi-metal and direct-gap semiconductor. The band structure and densities of states of the nanoribbons indicated that low energy bands contributed to edge states. Different hydrogen adsorption patterns on each edge induce two kinds of edge state on the nanoribbons and these two kinds of edge state have little effect on each other. The relationships between the bandgap and width of three types of nanoribbons were studied. Nanoribbons terminated with zero or eight hydrogen atoms in each unit cell have a bandgap that oscillates with width in a period of three, while the bandgap changes nonperiodically in those terminated with four hydrogen atoms.

Key words: Molybdenum disulfide, Nanoribbon, Dangling bond, Edge state, First-principles, Electronic structure

MSC2000: 

  • O641