Excellent thermoelectric properties of monolayer MoS2-MoSe2 aperiodic superlattices

Effective regulation of phonon thermal conductivity is crucial for the understanding of phonon transmission and improving thermoelectric (TE) performance. Using density functional theory (DFT) combined with the non-equilibrium Green's function (NEGF) method, we investigated the effect of phonon localization induced by aperiodic superlattices on the TE transport properties of superlattices based on monolayer MoS2-MoSe2. The results show that the structural defects obtained by changing the superlattice arrangement can effectively modulate the phonon thermal conductivity independently. In addition, the TE properties of the superlattices increase with temperature and central region length. The maximum value of the TE figure of merit of the aperiodic superlattice can reach 1.38 at 500 K. This implies a new potential strategy for tuning the TE performance of devices by exploiting the arrangements of the aperiodic superlattice.