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Title: Surface structure of bulk 2H-MoS 2 (0001) and exfoliated suspended monolayer MoS 2 : A selected area low energy electron diffraction study

Abstract

Here, we used selected area low energy electron diffraction intensity-voltage (μLEED-IV) analysis to investigate the surface structure of crystalline 2H molybdenum disulfide (MoS 2) and mechanically exfoliated and suspended monolayer MoS 2. Our results show that the surface structure of bulk 2H-MoS 2 is distinct from its bulk and that it has a slightly smaller surface relaxation at 320 K than previously reported at 95 K. We concluded that suspended monolayer MoS 2 shows a large interlayer relaxation compared to the MoS 2 sandwich layer terminating the bulk surface. The Debye temperature of MoS 2 was concluded to be about 600 K, which agrees with a previous theoretical study. Our work has shown that the dynamical μLEED-IV analysis performed with a low energy electron microscope (LEEM) is a powerful technique for determination of the local atomic structures of currently extensively studied two-dimensional (2-D) materials.

Authors:
 [1];  [2];  [1];  [3];  [2];  [2];  [1]
  1. Univ. of New Hampshire, Durham, NH (United States). Dept. of Physics and Materials Science Program
  2. Columbia Univ., New York, NY (United States)
  3. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1345750
Alternate Identifier(s):
OSTI ID: 1397406
Report Number(s):
BNL-113594-2017-JA
Journal ID: ISSN 0039-6028; R&D Project: 16083; KC0403020
Grant/Contract Number:
SC00112704; SC0012704; FG 02-04-ER-46157
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Surface Science
Additional Journal Information:
Journal Volume: 660; Journal Issue: C; Journal ID: ISSN 0039-6028
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; MoS2; μLEED-IV; 2-D material; Surface structure; LEEM

Citation Formats

Dai, Zhongwei, Jin, Wencan, Grady, Maxwell, Sadowski, Jerzy T., Dadap, Jerry I., Osgood, Richard M., and Pohl, Karsten. Surface structure of bulk 2H-MoS 2 (0001) and exfoliated suspended monolayer MoS 2 : A selected area low energy electron diffraction study. United States: N. p., 2017. Web. doi:10.1016/j.susc.2017.02.005.
Dai, Zhongwei, Jin, Wencan, Grady, Maxwell, Sadowski, Jerzy T., Dadap, Jerry I., Osgood, Richard M., & Pohl, Karsten. Surface structure of bulk 2H-MoS 2 (0001) and exfoliated suspended monolayer MoS 2 : A selected area low energy electron diffraction study. United States. doi:10.1016/j.susc.2017.02.005.
Dai, Zhongwei, Jin, Wencan, Grady, Maxwell, Sadowski, Jerzy T., Dadap, Jerry I., Osgood, Richard M., and Pohl, Karsten. Fri . "Surface structure of bulk 2H-MoS 2 (0001) and exfoliated suspended monolayer MoS 2 : A selected area low energy electron diffraction study". United States. doi:10.1016/j.susc.2017.02.005. https://www.osti.gov/servlets/purl/1345750.
@article{osti_1345750,
title = {Surface structure of bulk 2H-MoS 2 (0001) and exfoliated suspended monolayer MoS 2 : A selected area low energy electron diffraction study},
author = {Dai, Zhongwei and Jin, Wencan and Grady, Maxwell and Sadowski, Jerzy T. and Dadap, Jerry I. and Osgood, Richard M. and Pohl, Karsten},
abstractNote = {Here, we used selected area low energy electron diffraction intensity-voltage (μLEED-IV) analysis to investigate the surface structure of crystalline 2H molybdenum disulfide (MoS2) and mechanically exfoliated and suspended monolayer MoS2. Our results show that the surface structure of bulk 2H-MoS2 is distinct from its bulk and that it has a slightly smaller surface relaxation at 320 K than previously reported at 95 K. We concluded that suspended monolayer MoS2 shows a large interlayer relaxation compared to the MoS2 sandwich layer terminating the bulk surface. The Debye temperature of MoS2 was concluded to be about 600 K, which agrees with a previous theoretical study. Our work has shown that the dynamical μLEED-IV analysis performed with a low energy electron microscope (LEEM) is a powerful technique for determination of the local atomic structures of currently extensively studied two-dimensional (2-D) materials.},
doi = {10.1016/j.susc.2017.02.005},
journal = {Surface Science},
number = C,
volume = 660,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}

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