First-principle study of sulfur vacancy and O2adsorption on the electronic and optical properties of ferroelectric CuInP2S6monolayer

Sulfur vacancy in MoS2has been found to have an important influence on the performance of optoelectronic devices. Here, we study the effect of sulfur vacancy and O2adsorption on the electronic and optical properties in the two-dimensional ferroelectric CuInP2S6. It is revealed that a defect state ap...

Full description

Saved in:
Bibliographic Details
Published in:Journal of physics. Condensed matter 2020-05, Vol.32 (33)
Main Authors: Sun, Zhizheng, Huang, Hongfei, Xun, Wei, Shi, Shanjin, Hao, Xiang, Ju, Sheng, Wu, Yinzhong
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Sulfur vacancy in MoS2has been found to have an important influence on the performance of optoelectronic devices. Here, we study the effect of sulfur vacancy and O2adsorption on the electronic and optical properties in the two-dimensional ferroelectric CuInP2S6. It is revealed that a defect state appears at the top of valence band with the presence of sulfur vacancy. However, when O2is chemisorbed at sulfur vacancy, the defect state disappears. The variation of charge state and charge transfer are calculated and discussed. Although the ferroelectricity is greatly suppressed with the presence of sulfur vacancy, the ferroelectric state can be recovered when the O2is adsorbed. Within the framework of GW + BSE method, the optical absorption edge of CuInP2S6monolayer exhibits a red-shift for the presence of sulfur vacancy and further O2adsorption gives rise to a blue-shift of the spectrum. Our findings have shown an effective way to improve the functionality of two-dimensional ferroelectrics via defect engineering.
ISSN:1361-648X
DOI:10.1088/1361-648X/ab87d0