Remarkably high thermal-driven MoS₂ grain boundary migration mobility and its implications on defect healing

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) transition-metal dichalcogenides (TMDs) are promising for electronic devices.
• Controlling defects in TMDs like MoS2 is essential but challenging.

Purpose of the Study:

• Investigate the kinetics and dynamics of four distinct grain boundary (GB) types in monolayer MoS2.
• Understand how GBs influence defect control and material properties.

Main Methods:

• Computational exploration of GB migration behavior under thermal fluctuations and temperature gradients.
• Analysis of defect configurations and their temperature dependence.

Main Results:

• Significant disparity in migration mobility among the four studied GBs (S5|7, Mo5|7, S4|6, S6|8).
• S4|6 and S6|8 GBs show higher mobility, with an abnormal temperature relationship.
• High GB mobility facilitates defect annihilation and redistribution, impacting thermal conductivity.

Conclusions:

• GB dynamics in MoS2 are highly varied and controllable.
• GB engineering offers new pathways for defect management in 2D materials.
• Potential for developing novel electronic applications by manipulating GBs.