Thermal properties of monolayer MoS2 and WS2/MoS2 heterojunction under three strain states

In this paper, the thermal properties of single-layer MoS 2 and WS 2 /MoS 2 heterostructure under three strain states are systematically studied. The first-principles calculation method based on density functional theory is used to obtain the phonon dispersion curves and related thermal parameters of crystals. The results show that Van der Waals cleaves phonons only in the vertical direction. The thermal properties of the two crystals are changed by the application of biaxial compressive strain. Taking the monolayer MoS 2 as an example, the curves of the heat capacity and the Debye characteristic temperature of the monolayer MoS 2 under the three strain states of biaxial tension, biaxial compression and biaxial tension and compression are comprehensively analyzed. It is found that the thermal properties of the crystal will change differently in different strain states. And at high temperatures, the heat capacity is more sensitive to the effect of strain.