Preferential hole defect formation in monolayer WSe2 by electron-beam irradiation

Shin，Donghan1,5; Wang，Gang2,5; Han，Mengjiao2,3; Lin，Zeyu2; O'Hara，Andrew1; Chen，Feiyu2; Lin，Junhao2,3; Pantelides，Sokrates T.1,4

2021-04-01

10.1103/PhysRevMaterials.5.044002

Physical Review Materials   影响因子和分区

2475-9953

Monolayer transition-metal dichalcogenides (TMDCs) have been extensively studied due to their wide range of physical properties and applications. It has been demonstrated that the electron beam in a transmission electron microscope (TEM) or scanning TEM (STEM) generates chalcogen vacancies that agglomerate into dispersed linelike or holelike defects. Here we employ a STEM electron beam and demonstrate that, in WSe2, beam-induced chalcogen vacancies initially form certain dispersed multivacancy structures, as seen in TMDCs in prior work. However, with suitable control of the STEM focused electron beam, these multivacancies gradually evolve into a dense network of ten-, 12-, 14-, and 16-member ring round holes, whereas the same process leads predominantly to chalcogen-vacancy line defects in other trigonal-prismatic TMDCs. Density functional theory calculations find that the underlying atomic-scale processes lead preferentially to defect structures that lower the total energy so that we are able to track the formation of the observed multivacancy complexes, which then lead to the formation of dense large round holes in WSe2. The same processes in WS2, however, are energetically unfavorable, while linear multivacancy defects are preferred, as observed. The demonstrated control of the formation of unique high-density round holes in WSe2 has potential for applications such as atomic and molecular sieving.

SCI ; EI

英语

通讯

WOS:000655931900002

20211810274821

Defects ; Density functional theory ; Electron beams ; Electrons ; Monolayers ; Transition metals ; Transmission electron microscopy ; Tungsten compounds

Metallurgy and Metallography:531 ; Probability Theory:922.1 ; Materials Science:951

2-s2.0-85104842996

Scopus

1.Department of Physics and Astronomy,Vanderbilt University,Nashville,37235,United States
2.Department of Physics,Southern University of Science and Technology,Shenzhen,518055,China
3.Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices,Southern University of Science and Technology,Shenzhen,518055,China
4.Department of Electrical Engineering and Computer Science,Vanderbilt University,Nashville,37235,United States
5.

Shin，Donghan,Wang，Gang,Han，Mengjiao,et al. Preferential hole defect formation in monolayer WSe2 by electron-beam irradiation[J]. Physical Review Materials,2021,5(4).

Shin，Donghan.,Wang，Gang.,Han，Mengjiao.,Lin，Zeyu.,O'Hara，Andrew.,...&Pantelides，Sokrates T..(2021).Preferential hole defect formation in monolayer WSe2 by electron-beam irradiation.Physical Review Materials,5(4).

Shin，Donghan,et al."Preferential hole defect formation in monolayer WSe2 by electron-beam irradiation".Physical Review Materials 5.4(2021).