Abstract
Triangular nanovoids in 2D materials transition metal dichalcogenides have vertex points that cause stress concentration and lead to sharp crack propagation and failure. Here, the atomistic mechanics of back folding around triangular nanovoids in monolayer WS2 sheets is examined. Combining atomic-resolution images from annular dark-field scanning transmission electron microscopy with reactive molecular modelling, it is revealed that the folding edge formation has statistical preferences under geometric conditions based on the orientation mismatch. It is further investigated how loading directions and strong interlayer friction, interplay with WS2 lattice's crack preference, govern the deformation and fracture pattern around folding edges. These results provide fundamental insights into the combination of fracture and folding in flexible monolayer crystals and the resultant Moiré lattices.
Original language | English |
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Article number | 2104238 |
Journal | Small |
Volume | 17 |
Issue number | 52 |
DOIs | |
State | Published - Dec 29 2021 |
Externally published | Yes |
Funding
G.H.R. and G.S.J. contributed equally to this work. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (no. 2020R1G1A1099542). G.S.J. acknowledges support by the Laboratory Directed Research and Development (LDRD) Program of Oak Ridge National Laboratory (Eugene P. Wigner Fellowship). This research used resources of the Compute and Data Environment for Science (CADES) at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract no. DE‐AC05‐00OR22725.