Strain-Dependent Edge Structures in MoS₂ Layers

Strain-Dependent Edge Structures in MoS₂ Layers

Tinoco Rivas, M. (TU Delft QN/Conesa-Boj Lab; Kavli institute of nanoscience Delft)
Maduro, L.A. (TU Delft QN/Conesa-Boj Lab; Kavli institute of nanoscience Delft)
Masaki, Mukai (JEOL Ltd., Japan)
Okunishi, Eiji (JEOL Ltd., Japan)
Conesa Boj, S. (TU Delft QN/Conesa-Boj Lab; Kavli institute of nanoscience Delft)

2017-11-08

Edge structures are low-dimensional defects unavoidable in layered materials of the transition metal dichalcogenides (TMD) family. Among the various types of such structures, the armchair (AC) and zigzag (ZZ) edge types are the most common. It has been predicted that the presence of intrinsic strain localized along these edges structures can have direct implications for the customization of their electronic properties. However, pinning down the relation between local structure and electronic properties at these edges is challenging. Here, we quantify the local strain field that arises at the edges of MoS₂ flakes by combining aberration-corrected transmission electron microscopy (TEM) with the geometrical-phase analysis (GPA) method. We also provide further insight on the possible effects of such edge strain on the resulting electronic behavior by means of electron energy loss spectroscopy (EELS) measurements. Our results reveal that the two-dominant edge structures, ZZ and AC, induce the formation of different amounts of localized strain fields. We also show that by varying the free edge curvature from concave to convex, compressive strain turns into tensile strain. These results pave the way toward the customization of edge structures in MoS₂, which can be used to engineer the properties of layered materials and thus contribute to the optimization of the next generation of atomic-scale electronic devices built upon them.

aberration-corrected transmission electron microscopy
edge structures
electron energy loss spectroscopy
strain
Transition-metal dichalcogenides

http://resolver.tudelft.nl/uuid:e4e1c530-252d-44d2-9df3-66e2ce5e52cc

https://doi.org/10.1021/acs.nanolett.7b03627

1530-6984

Nano Letters: a journal dedicated to nanoscience and nanotechnology, 17 (11), 7021-7026

Institutional Repository

journal article

© 2017 M. Tinoco Rivas, L.A. Maduro, Mukai Masaki, Eiji Okunishi, S. Conesa Boj