Mechanical properties of lateral transition metal dichalcogenide heterostructures

Abstract

Transition metal dichalcogenide (TMD) monolayers attract great attention due to their specific structural, electronic and mechanical properties. The formation of their lateral heterostructures allows a new degree of flexibility in engineering electronic and optoelectronic devices.However, the mechanical properties of the lateral heterostructures are rarely investigated. In this study, a comparative investigation on the mechanical characteristics of 1H, 1T' and 1H/1T' heterostructure phases of different TMD monolayers including molybdenum disulfide (MoS2) molybdenum diselenide (MoSe2), Tungsten disulfide (WS2), and Tungsten diselenide (WSe2) was conducted by means of density functional theory (DFT) calculations. Our results indicate that the lateral heterostructures have a relatively weak mechanical strength for all the TMD monolayers. The significant correlation between the mechanical properties of the TMD monolayers and their structural phases can be used to tune their stiffness of the materials. Our findings, therefore, suggest a novel strategy to manipulate the mechanical characteristics of TMDs by engineering their structural phases for their practical applications.

Multiscale numerical simulation of in-plane mechanical properties of two-dimensional monolayers

“…Including MoS 2 , molybdenum diselenide (MoSe 2 ), tungsten disulde (WS 2 ), and tungsten diselenide (WSe 2 ). 83 Their results reveal that the impact of the structural phase is signicant (Fig. 9).…”

“…9 In-plane stiffness tensors C ij of TMDs with different structural phases from the ref. 83. calculation to study the impact of the structural phases on the mechanical properties of 1H, 1T 0 and 1H/1T 0 heterostructure phases of different TMD monolayers.…”

“…Some 2D materials can display several atomic structures that are either sufficiently close in energy to be experimentally observable or stabilized through substrates or doping. For such 2D congurations, the atomic arrangement can signicantly affect the physical properties of the system [73][74][75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90][91] (e.g. TMDs).…”

“…TMDs are one family of well-studied 2D material due to their diverse physical properties in terms of their structural phases. 83,92 As an instance, molybdenum disulde (MoS 2 ) is reported to be most stable in its 1H semiconducting-like structural phase. However, it has also displayed to be metallic and unstable in its 1T structural phase.…”

“…Evaluating the characteristics of 2D titanium carbide applying DFT-D3 calculation to predict their mechanical properties of these 2D materials Imani Yengejeh et al 83 TMDs GGA-PBE Mechanical properties Investigating the impact of hetero-structure phase on the mechanical properties of TMD monolayers concluding that the fracture stress decreases substantially inversely proportional to the defect density. Their latter attempt was made for potential applications which require non-pristine sheets such as ltration membranes.…”