Sub-nanometre channels embedded in two-dimensional materials.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) materials offer atomic thinness for flexible electronics and length scaling.
• Existing 2D devices include p-n junctions, metal-semiconductor contacts, and metal-insulator barriers.
• Precise nanoscale control over lateral dimensions is crucial for advanced 2D electronic devices.

Purpose of the Study:

• To report the direct synthesis of sub-nanometre-wide one-dimensional (1D) molybdenum disulfide (MoS2) channels embedded within tungsten diselenide (WSe2) monolayers.
• To investigate the formation of coherent interfaces and 2D superlattices using a dislocation-catalysed approach.
• To explore the potential of these 1D channels for future electronic applications requiring carrier confinement and charge separation.

Main Methods:

• Direct synthesis of 1D MoS2 channels within WSe2 monolayers via a dislocation-catalysed approach.
• Characterization of channel interfaces for misfit dislocations and dangling bonds.
• Molecular dynamics simulations to identify other 2D material combinations for 1D channel formation.

Main Results:

• Successfully synthesized sub-nanometre-wide 1D MoS2 channels embedded in WSe2 monolayers.
• Achieved 1D channels with dislocation- and dangling bond-free edges, forming coherent interfaces.
• Demonstrated periodic dislocation arrays creating 2D superlattices of these 1D channels.
• Identified other 2D material systems capable of forming 1D channels through simulations.

Conclusions:

• The dislocation-catalysed approach enables the creation of highly controlled 1D channels within 2D materials.
• These coherent 1D channels and superlattices are promising for next-generation electronics.
• The electronic band structure suggests potential for carrier confinement and charge separation, crucial for ultimate length scaling in electronics.