Effect of defects on the electronic structure of a PbI2/MoS2 van der Waals heterostructure: A first-principles study  

作　　者：Wen He HuaWei Li HuiQiong Zhou HongKang Zhao Hui Wang XingHua Shi 

机构地区：[1]School of Physics,Beijing Institute of Technology,Beijing 100081,China [2]Laboratory of Theoretical and Computational Nanoscience,CAS Key Laboratory for Nanosystem and Hierarchy Fabrication,CAS Center for Excellence in Nanoscience,National Center for Nanoscience and Technology,Chinese Academy of Sciences,Beijing 100190,China [3]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2020年第3期64-69,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：National Natural Science Foundation of China(Grant No.11672079);the National Science Foundation of Beijing(Grant No.2184130)。

摘　　要：PbI2/MoS2,as a typical van der Waals(vdW)heterostructure,has attracted intensive attention owing to its remarkable electronic and optoelectronic properties.In this work,the effect of defects on the electronic structures of a PbI2/MoS2 heterointerface has been systematically investigated.The manner in which the defects modulate the band structure of PbI2/MoS2,including the band gap,band edge,band alignment,and defect energy-level density within the band gap is discussed herein.It is shown that sulfur defects tune the band gaps,iodine defects shift the positions of the band edge and Fermi level,and lead defects realize the conversions between the straddling-gap band alignment and valence-band-aligned gap,thus enhancing the light-absorption ability of the material.PbI2/MoS2, as a typical van der Waals（vdW） heterostructure, has attracted intensive attention owing to its remarkable electronic and optoelectronic properties. In this work, the effect of defects on the electronic structures of a PbI2/MoS2 heterointerface has been systematically investigated. The manner in which the defects modulate the band structure of PbI2/MoS2, including the band gap, band edge, band alignment, and defect energy-level density within the band gap is discussed herein. It is shown that sulfur defects tune the band gaps, iodine defects shift the positions of the band edge and Fermi level, and lead defects realize the conversions between the straddling-gap band alignment and valence-band-aligned gap, thus enhancing the light-absorption ability of the material.

关 键 词：defect engineering electronic structures PbI2/MoS2 VAN der WAALS HETEROSTRUCTURE FIRST-PRINCIPLES study 

分 类 号：O572.322[理学—粒子物理与原子核物理] TB34[理学—物理]