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Title: Growth of Highly Oriented (VNbMoTaW)S 2 Layers
Compositional tunability, an indispensable parameter to modify materials' properties, can open up new applications for the class of van der Waals (vdW) layered materials such as transition-metal dichalcogenides (TMDCs). To-date, multi-element alloy TMDC layers are obtained via exfoliation from bulk polycrystalline powders. Here, we demonstrate direct deposition of high-entropy alloy disulfide, (VNbMoTaW)S2, layers with controllable thicknesses on free-standing graphene membranes and on bare and hBN-covered Al2O3(0001) substrates via ultra-high vacuum reactive dc magnetron sputtering of VNbMoTaW target in Kr and H2S gas mixtures. Using a combination of density functional theory calculations, Raman spectroscopy, X-ray diffraction, scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy, we determine that the as-deposited layers are single-phase, 2H-structured, and 0001-oriented (V0.10Nb0.16Mo0.19Ta0.28W0.27)S2.44. Our synthesis route is general and applicable for heteroepitaxial growth of a wide variety of TMDC alloys and potentially other multielement alloy vdW compounds with the desired compositions.  more » « less
Award ID(s):
2211350 2245008
PAR ID:
10556795
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Nano Letters
Volume:
24
Issue:
1
ISSN:
1530-6984
Page Range / eLocation ID:
493 to 500
Subject(s) / Keyword(s):
transition-metal dichalcogenides, multielement, high-entropy, sputter deposition, highly oriented growth
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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