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Title: A Self-Limiting Electro-Ablation Technique for the Top-Down Synthesis of Large-Area Monolayer Flakes of 2D Materials

Abstract

We report the discovery of an electrochemical process that converts two dimensional layered materials of arbitrary thicknesses into monolayers. The lateral dimensions of the monolayers obtained by the process within a few seconds time at room temperature were as large as 0.5 mm. The temporal and spatial dynamics of this physical phenomenon, studied on MoS2 flakes using ex-situ AFM imaging, Raman mapping, and photoluminescence measurements trace the origin of monolayer formation to a substrate-assisted self-limiting electrochemical ablation process. Electronic structure and atomistic calculations point to the interplay between three essential factors in the process: (1) strong covalent interaction of monolayer MoS2 with the substrate; (2) electric-field induced differences in Gibbs free energy of exfoliation; (3) dispersion of MoS2 in aqueous solution of hydrogen peroxide. This process was successful in obtaining monolayers of other 2D transition metal dichalcogenides, like WS2 and MoTe2 as well.

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science - Office of Basic Energy Sciences - Chemical Sciences, Geosciences, and Biosciences Division
OSTI Identifier:
1391682
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Scientific Reports; Journal Volume: 6; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Atomistic calculations; Electrochemistry; Interfaces; Transition metal dichalcogenides; Two-dimensional materials

Citation Formats

Das, Saptarshi, Bera, Mrinal K., Tong, Sheng, Narayanan, Badri, Kamath, Ganesh, Mane, Anil, Paulikas, Arvydas P., Antonio, Mark R., Sankaranarayanan, Subramanian K. R. S., and Roelofs, Andreas K. A Self-Limiting Electro-Ablation Technique for the Top-Down Synthesis of Large-Area Monolayer Flakes of 2D Materials. United States: N. p., 2016. Web. doi:10.1038/srep28195.
Das, Saptarshi, Bera, Mrinal K., Tong, Sheng, Narayanan, Badri, Kamath, Ganesh, Mane, Anil, Paulikas, Arvydas P., Antonio, Mark R., Sankaranarayanan, Subramanian K. R. S., & Roelofs, Andreas K. A Self-Limiting Electro-Ablation Technique for the Top-Down Synthesis of Large-Area Monolayer Flakes of 2D Materials. United States. doi:10.1038/srep28195.
Das, Saptarshi, Bera, Mrinal K., Tong, Sheng, Narayanan, Badri, Kamath, Ganesh, Mane, Anil, Paulikas, Arvydas P., Antonio, Mark R., Sankaranarayanan, Subramanian K. R. S., and Roelofs, Andreas K. 2016. "A Self-Limiting Electro-Ablation Technique for the Top-Down Synthesis of Large-Area Monolayer Flakes of 2D Materials". United States. doi:10.1038/srep28195.
@article{osti_1391682,
title = {A Self-Limiting Electro-Ablation Technique for the Top-Down Synthesis of Large-Area Monolayer Flakes of 2D Materials},
author = {Das, Saptarshi and Bera, Mrinal K. and Tong, Sheng and Narayanan, Badri and Kamath, Ganesh and Mane, Anil and Paulikas, Arvydas P. and Antonio, Mark R. and Sankaranarayanan, Subramanian K. R. S. and Roelofs, Andreas K.},
abstractNote = {We report the discovery of an electrochemical process that converts two dimensional layered materials of arbitrary thicknesses into monolayers. The lateral dimensions of the monolayers obtained by the process within a few seconds time at room temperature were as large as 0.5 mm. The temporal and spatial dynamics of this physical phenomenon, studied on MoS2 flakes using ex-situ AFM imaging, Raman mapping, and photoluminescence measurements trace the origin of monolayer formation to a substrate-assisted self-limiting electrochemical ablation process. Electronic structure and atomistic calculations point to the interplay between three essential factors in the process: (1) strong covalent interaction of monolayer MoS2 with the substrate; (2) electric-field induced differences in Gibbs free energy of exfoliation; (3) dispersion of MoS2 in aqueous solution of hydrogen peroxide. This process was successful in obtaining monolayers of other 2D transition metal dichalcogenides, like WS2 and MoTe2 as well.},
doi = {10.1038/srep28195},
journal = {Scientific Reports},
number = 1,
volume = 6,
place = {United States},
year = 2016,
month = 6
}
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