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Title: Toward understanding the phase-selective growth mechanism of films and geometrically-shaped flakes of 2D MoTe 2
Two-dimensional (2D) molybdenum ditelluride (MoTe 2 ) is an interesting material for fundamental study and applications, due to its ability to exist in different polymorphs of 2H, 1T, and 1T′, their phase change behavior, and unique electronic properties. Although much progress has been made in the growth of high-quality flakes and films of 2H and 1T′-MoTe 2 phases, phase-selective growth of all three phases remains a huge challenge, due to the lack of enough information on their growth mechanism. Herein, we present a novel approach to growing films and geometrical-shaped few-layer flakes of 2D 2H-, 1T-, and 1T′-MoTe 2 by atmospheric-pressure chemical vapor deposition (APCVD) and present a thorough understanding of the phase-selective growth mechanism by employing the concept of thermodynamics and chemical kinetics involved in the growth processes. Our approach involves optimization of growth parameters and understanding using thermodynamical software, HSC Chemistry. A lattice strain-mediated mechanism has been proposed to explain the phase selective growth of 2D MoTe 2 , and different chemical kinetics-guided strategies have been developed to grow MoTe 2 flakes and films.  more » « less
Award ID(s):
2122044 1831133
PAR ID:
10324258
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
RSC Advances
Volume:
11
Issue:
61
ISSN:
2046-2069
Page Range / eLocation ID:
38839 to 38848
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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