Theoretical study of Cr2X3S3 (X = Br, I) monolayers for thermoelectric and spin caloritronics properties

High curie temperature 2D materials are important for the progress of the field of spin caloritronics. The spin Seebeck effect and conventional thermoelectric figure of merit (ZT) can give a great insight into how these 2D magnetic materials will perform in spin caloritronics applications. Here in this paper, we have systematically studied 2D Janus monolayers based on CrX3 monolayers. We obtain a ZT of 0.31 and 0.21 for the Cr2Br3S3 and Cr2I3S3 Janus monolayers. The spin Seebeck coefficient obtained at room temperature is also very high (similar to 1570 mu VK-1 in the hole-doped region and similar to 1590 mu VK-1 in the electron-doped region). The thermal conductivity of these monolayers (similar to 22 Wm(-1) K-1 for Cr2Br3S3 and similar to 16 Wm(-1) K-1 for Cr2I3S3) are also very similar to other 2D semiconductor transition metals chalcogenides. These findings suggest a high potential for these monolayers in the spin caloritronics field.