Engineering the Crack Structure and Fracture Behavior in Monolayer MoS2 By Selective Creation of Point Defects

Wang，Gang1; Wang，Yun Peng2; Li，Songge1; Yang，Qishuo1; Li，Daiyue1; Pantelides，Sokrates T.3; Lin，Junhao1

2022

10.1002/advs.202200700

Advanced Science   影响因子和分区

2198-3844

Monolayer transition-metal dichalcogenides, e.g., MoS, typically have high intrinsic strength and Young's modulus, but low fracture toughness. Under high stress, brittle fracture occurs followed by cleavage along a preferential lattice direction, leading to catastrophic failure. Defects have been reported to modulate the fracture behavior, but pertinent atomic mechanism still remains elusive. Here, sulfur (S) and MoS point defects are selectively created in monolayer MoS using helium- and gallium-ion-beam lithography, both of which reduce the stiffness of the monolayer, but enhance its fracture toughness. By monitoring the atomic structure of the cracks before and after the loading fracture, distinct atomic structures of the cracks and fracture behaviors are found in the two types of defect-containing monolayer MoS. Combined with molecular dynamics simulations, the key role of individual S and MoS point defects is identified in the fracture process and the origin of the enhanced fracture toughness is elucidated. It is a synergistic effect of defect-induced deflection and bifurcation of cracks that enhance the energy release rate, and the formation of widen crack tip when fusing with point defects that prevents the crack propagation. The findings of this study provide insights into defect engineering and flexible device applications of monolayer MoS.

atomic imaging crack propagation fracture behavior monolayer MoS2 point defects

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China[11974156,12004439] ; Guangdong International Science Collaboration Project[2019A050510001] ; Guangdong Innovative and Entrepreneurial Research Team Program[2019ZT08C044] ; Shenzhen Science and Technology Program["KQTD20190929173815000",20200925161102001] ; Science, Technology and Innovation Commission of Shenzhen Municipality[ZDSYS20190902092905285]

Chemistry ; Science & Technology - Other Topics ; Materials Science

Chemistry, Multidisciplinary ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary

WOS:000802157800001

WILEY

20222212176960

Atoms ; Crack propagation ; Crack tips ; Elastic moduli ; Fracture toughness ; Ion beams ; Layered semiconductors ; Molecular dynamics ; Monolayers ; Point defects ; Sulfur compounds ; Transition metals

Metallurgy and Metallography:531 ; Semiconducting Materials:712.1 ; Physical Chemistry:801.4 ; Atomic and Molecular Physics:931.3 ; High Energy Physics:932.1 ; Crystal Lattice:933.1.1 ; Materials Science:951

2-s2.0-85130892581

Scopus

1.Department of Physics and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices,Southern University of Science and Technology,Shenzhen,518055,China
2.School of Physics and Electronics,Hunan Key Laboratory for Super-Micro Structure and Ultrafast Process,Central South University,Changsha,932 South Lushan Road,410083,China
3.Department of Physics and Astronomy and Department of Electrical and Computer Engineering,Vanderbilt University,Nashville,37235,United States

Wang，Gang,Wang，Yun Peng,Li，Songge,et al. Engineering the Crack Structure and Fracture Behavior in Monolayer MoS2 By Selective Creation of Point Defects[J]. Advanced Science,2022,9.

Wang，Gang.,Wang，Yun Peng.,Li，Songge.,Yang，Qishuo.,Li，Daiyue.,...&Lin，Junhao.(2022).Engineering the Crack Structure and Fracture Behavior in Monolayer MoS2 By Selective Creation of Point Defects.Advanced Science,9.

Wang，Gang,et al."Engineering the Crack Structure and Fracture Behavior in Monolayer MoS2 By Selective Creation of Point Defects".Advanced Science 9(2022).