Presentation Information
[23a-31B-6]Energetics and electronic properties of scrolled Janus WSSe
〇YANLIN GAO1, Okada Susumu1 (1.University of Tsukuba)
Keywords:
Scrolled WSSe,Electronic structures,Type II band edge alignment
Janus transition metal dichalcogenides (TMDs) have a structural asymmetry with respect to their atomic layers, since its transition metal layer is sandwiched by different chalcogen layers. This structural asymmetry causes dipole moment normal to the layer, which makes Janus TMDs unique materials in the field of material science and technologies. The Janus TMDs have unique electronic properties because of the dipole moment across the layer. The structural asymmetry also leads to the unique morphology: scrolled structures where the Janus TMDs release asymmetric strains on both chalcogen layers. Although experiments reported the scrolled conformation of WSSe and MoSSe, their energetics and electronic properties are not yet addressed. Therefore, in this work, we investigate the energetics and electronic structures of scrolled Janus WSSe with the density functional theory with the generalized gradient approximation.
Our results showed that the electronic structure of scrolled WSSe is sensitive to the atomic position of the W in the scrolled conformation.The band edges of W atoms in the inner shell shift upward and those in the outer shell shift downwards. Accordingly, the scrolled WSSe possesses a type II band edge alignment, even though it has homogeneous structure. We found that the electrostatic potential of the inner shell is shallower than that of the outer shell because of the cooperation of radial dipole moment of inner and outer shells.
Our results showed that the electronic structure of scrolled WSSe is sensitive to the atomic position of the W in the scrolled conformation.The band edges of W atoms in the inner shell shift upward and those in the outer shell shift downwards. Accordingly, the scrolled WSSe possesses a type II band edge alignment, even though it has homogeneous structure. We found that the electrostatic potential of the inner shell is shallower than that of the outer shell because of the cooperation of radial dipole moment of inner and outer shells.