Theoretical prediction of high electron mobility in multilayer MoS₂ heterostructured with MoSe₂

Two-dimensional (2D) MoS₂ has been considered to be one of the most promising semiconducting materials with the potential to be used in novel nanoelectronic devices. High carrier mobility in the semiconductor is necessary to guarantee a low power dissipation and a high switch speed of the corresponding electronic device. Strain engineering in 2D materials acts as an important approach to tailor and design their electronic and carrier transport properties. In this work, strain is introduced to MoS₂ through perpendicularly building van der Waals heterostructures MoSe₂-MoS₂. Our first-principles calculations demonstrate that acoustic-phonon-limited electron mobility can be significantly enhanced in the heterostructures compared with that in pure multilayer MoS₂. It is found that the effective electron mass and the deformation potential constant are relatively smaller in the heterostructures, which is responsible for the enhancement in the electron mobility. Overall, the electron mobility in the heterostructures is about 1.5 times or more of that in pure multilayer MoS₂ with the same number of layers for the studied structures. These results indicate that MoSe₂ is an excellent material to be heterostructured with multilayer MoS₂ to improve the charge transport property.