MoS₂ heterostructure with tunable phase stability: strain induced interlayer covalent bond formation.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Molybdenum disulfide (MoS2) exhibits a structural phase transition crucial for nanoelectronic devices.
• Elastic strain engineering is explored for phase transition control and ferroelastic behavior in MoS2 nanostructures.
• High elastic strain requirements currently limit experimental realization of MoS2 phase transitions.

Purpose of the Study:

• To investigate methods for reducing the critical strain required for phase transitions in monolayer MoS2.
• To explore the potential of heterostructures with buckled 2D materials for strain engineering MoS2.
• To identify novel applications for engineered MoS2 nanostructures.

Main Methods:

• Density functional theory (DFT) calculations were employed.
• The study focused on heterostructures formed between MoS2 and buckled 2D materials like silicene, germanene, and stanene.
• Critical phase transition strains (uniaxial and biaxial) were calculated for various heterostructures.

Main Results:

• Heterostructures with buckled 2D materials drastically reduce the critical phase transition strain in MoS2.
• Sandwiched structures of MoS2 with silicene or stanene show significantly reduced critical strains (∼0.06 uniaxial, ∼0.03 biaxial).
• These reduced strains are well within the experimental elastic limits.

Conclusions:

• Forming heterostructures with buckled 2D materials provides an experimentally achievable strategy for flexible phase transition design in MoS2.
• Identified MoS2 heterostructures are promising 2D candidates for shape memory devices and pseudoelasticity applications.
• This research paves the way for advanced nanoelectronic devices utilizing controlled phase transitions in MoS2.