First-Principles Study of Electronic Structure and Optical Properties of Silicon/Carbon Nanotube

• 作者: Guixia Li Jiangang Xu Wenyu Wang Yunguang Zhang
• 来源期刊: 计算化学(英文)
• 学科: 化学
• 关键词: NANOTUBES ELECTRONIC Structure OPTICAL Properties FIRST-PRINCIPLES
• 年，卷（期）: jshxyw_2017,（4）
• 页码范围: 159-171
• 页数: 13页
• 分类号: O6

摘要

A supercell of a nanotube formed by a carbon nanotube (CNT) and a silicon nanotube (SiNT) is established. The electronic structure and optical properties are implemented through the first-principles method based on the density functional theory (DFT) with the generalized gradient approximation (GGA). The calculated results show that (6, 6) - (6, 6) silicon/carbon nanotubes (Si/CNTs) presented a direct band gap of 0.093 eV, (4, 4) - (6, 6) silicon/carbon nanotubes presented a direct band gap of 0.563 eV. The top of valence band was fundamentally determined by the Si-3p states and C-2p states, and the bottom of conduction band was primarily occupied by the C-2p states and Si-3p states in the Si/CNTs. It was found that (6, 6) - (6, 6) Si/CNTs have smaller energy band gap and better conductivity. Besides, Si/CNTs have satisfactory absorption characteristics and luminous efficiency in ultraviolet band.