First-Principles Study of Lattice Thermal Conductivity in Janus MoSSe Bilayers with Different Stacking Modes

Recently, derivatives of molybdenum disulfide have attracted considerable attention. Among them, the thermal conductivity of Janus-based MoSSe SeS, SeSe and SS bilayers has not been investigated. Along these lines, in this work, the lattice thermal conductivities of Janus MoSSe-based bilayer structures were examined. More specifically, three different combined modes were used, including SMoSe/SMoSe (SeS stacking), SMoSe/SeMoS (SeSe stacking) and SeMoS/SMoSe (SS stacking), based on first-principles calculations. The extracted results show that the lattice thermal conductivity of all three structures is decreased with increasing temperature, whereas the SeS structure has a maximum lattice thermal conductivity value of about 22 W/mK at 300 K. The SS structure exhibits also the strongest phonon anharmonicity and highest phonon scattering effects, which leads to the smallest lattice thermal conductivity value of about 1.57 W/mK in the x-direction at room temperature, rendering the proposed configuration well suited for thermoelectric applications.