期刊
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
卷 149, 期 -, 页码 -出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.mssp.2022.106904
关键词
Double-walled silicon nanotubes; DFTB; Vacancy defect; Electric field; Electrical properties
类别
资金
- Natural Science Foundation of Liaoning Province, China [2019-BS-202]
- National Natural Science Foundation of China [52171187]
In this study, the effects of vacancy defects and external electric field on the geometrically structural optimization and electronic properties of DWSiNTs have been investigated using the SCCDFTB method. The results demonstrate that the chirality index of the tube, vacancy defects, and electric field significantly influence the atomic arrangement, quantum molecular descriptors, charge distribution, stability, energy gap, and Fermi energy levels. Additionally, the introduction of defects leads to a broadened range of charge transfer, with the direction of charge transfer in the applied electric field being opposite to the field direction.
As a new candidate material, silicon nanotubes (SiNTs) have been widely studied. However, various types of structural defects and external electric field are usually inescapability introduced in the experimental process of SiNTs synthesis. Structures, stability and electronic properties of the materials especially for double-walled silicon nanotubes (DWSiNTs) require to be considered. In this work, effects of vacancy defects and external electric field on properties of the geometrically structural optimization and electronic properties of DWSiNTs zigzag (3,0) @(7,0) and armchair (3,3)@(7,7) are studied via the self-consistent charge density functional tight binding (SCCDFTB) method. The results of us show that the regular arrangement of the atoms, quantum molecular descriptors, distribution of charge, the degree of warping, stability, energy gap and Fermi energy levels intensely hinge on the chirality index of the tube and impacts of vacancy defects and electric field. Especially, the appearance of monovacancy and the change of vacancy density have the most significant effect on the band gap. For the pristine tubes, the charges transfer from the inside to the outside along the radial direction of the tube exhibiting an axisymmetric distribution. With the introduction of defects, the range of the charge transfer is broadened dramatically. The direction of charge transfer in the applied electric field is always opposite to the field direction. Our work may provide a new route to tune the electronic properties of DWSiNTs and opens a wider field of its application in nano-electronic devices.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据