Two-dimensional (2D) materials exhibit excellent thermoelectric performance attributable to their lower dimensions. Through quantum transport theoretical calculations, we find that the asymmetric Janus monolayer materials (HfSSe and ZrSSe) possess the thermoelectric advantages of two interfaces (S and Se) simultaneously at both room temperature and high temperatures. The interface effect will directionally enhance the thermoelectric figure of merit (ZT) of in-plane heterostructures along the direction perpendicular to the interface. In addition, the introduction of structural dislocations at the interface can significantly enhance the ZT value of the in-plane heterostructure in the transport along the direction parallel to the interface. At the same time, by adjusting the ratio of the two materials at the interface, the optimal ZT of the in-plane heterostructure along the transport direction parallel to the interface can be enhanced to 1.63 (3.4) at 300 K (800 K). Furthermore, we propose that employing laser ablation to fabricate vertical heterostructures into graphical superlattices can substantially decrease the lattice thermal conductivity of the structure, thereby enhancing the thermoelectric performance of the material significantly. Our study provides theoretical support for enhancing the thermoelectric performance of 2D materials.
Shang et al. (Thu,) studied this question.