Dynamic Phase Engineering of Bendable Transition Metal Dichalcogenide Monolayers

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) materials, particularly transition metal dichalcogenide (TMD) monolayers, offer tunable optoelectronic properties.
• Strain and phase engineering are key methods for modifying these properties.
• Structural transformations between semiconducting (H) and metallic/semimetallic (T") phases can be induced in TMDs.

Purpose of the Study:

• To classify displacive structural transformations in Group VI TMDs.
• To develop a multiscale modeling framework for microstructural domain evolution in 2D monolayers.
• To demonstrate control over domain morphology and mechanical response for creating programmable materials.

Main Methods:

• First-principles calculations informed a multiscale modeling framework.
• Analysis of microstructural domain morphologies in elastically bendable 2D monolayers.
• Application of uniform and local strain to induce phase transformations.

Main Results:

• A classification of displacive transformations in Group VI TMDs was established.
• A modeling framework was formulated to describe domain evolution.
• Functional patterns of conductive T" domains were generated using controlled strain application.
• Dynamically programmable electromechanical 2D materials were demonstrated.

Conclusions:

• Controlled strain application allows for the dynamic patterning of conductive domains within semiconducting TMD monolayers.
• These engineered 2D materials can be rapidly switched between different transport states.
• This capability enables real-time device rewiring and opens avenues for novel device functionalities.