Tuning the Band Gap in Silicene by Oxidation

被引：165

作者：

Du, Yi ^{[1
]}

Zhuang, Jincheng ^{[1
]}

Liu, Hongsheng ^{[3
]}

Xu, Xun ^{[1
]}

Eilers, Stefan ^{[1
]}

Wu, Kehui ^{[2
]}

Cheng, Peng ^{[2
]}

Zhao, Jijun ^{[3
]}

Pi, Xiaodong ^{[4
,5
]}

See, Khay Wai ^{[1
]}

Peleckis, Germanas ^{[1
]}

Wang, Xiaolin ^{[1
]}

Dou, Shi Xue ^{[1
]}

机构：

[1] Univ Wollongong, ISEM, Wollongong, NSW 2525, Australia

[2] Chinese Acad Sci, Inst Phys, Beijing 100080, Peoples R China

[3] Dalian Univ Technol, Minist Educ, Key Lab Mat Modificat Laser Ion & Electron Beams, Dalian 116024, Peoples R China

[4] Zhejiang Univ, State Key Lab Silicon Mat, Hangzhou 310027, Zhejiang, Peoples R China

[5] Zhejiang Univ, Dept Mat Sci & Engn, Hangzhou 310027, Zhejiang, Peoples R China

来源：

ACS NANO | 2014年 / 8卷 / 10期

基金：

澳大利亚研究理事会; 中国国家自然科学基金;

关键词：

silicene; oxidation; band gap; STM; DFT calculation;

D O I：

10.1021/nn504451t

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Silicene monolayers grown on Ag(111) surfaces demonstrate a band gap that is tunable by oxygen adatoms from semimetallic to semiconducting type. With the use of low-temperature scanning tunneling microscopy, we find that the adsorption configurations and amounts of oxygen adatoms on the silicene surface are critical for band gap engineering, which is dominated by different buckled structures in root 13 x root 13, 4 x 4, and 2 root 3 x 2 root 3 silicene layers. The Si-O-Si bonds are the most energy-favored species formed on root 13 x root 13, 4 x 4, and 2 root 3 x 2 root 3 structures under oxidation, which is verified by in situ Raman spectroscopy as well as first-principles calculations. The silicene monolayers retain their structures when fully covered by oxygen adatoms. Our work demonstrates the feasibility of tuning the band gap of silicene with oxygen adatoms, which, in turn, expands the base of available two-dimensional electronic materials for devices with properties that is hardly achieved with graphene oxide.

引用

页码：10019 / 10025

页数：7

共 31 条

[1] STRUCTURAL INFORMATION FROM THE RAMAN-SPECTRUM OF AMORPHOUS-SILICON [J].