Effect of sulphur vacancy and interlayer interaction on the electronic structure and spin splitting of bilayer MoS₂

Abstract

Molybdenum disulfide (MoS2) is one of candidate materials for nanoelectronics and optoelectronics devices in future. The electronic and magnetic properties of MoS2 can be regulated by interlayer interaction and vacancy effect. Nevertheless, the combined effect of these two factors on MoS2 is not clearly understood. In this study, we have investigated the impact of single S vacancy combined with interlayer interaction on the properties of bilayer MoS2. Our calculated results show that S vacancy brings impurity states in the band structure of bilayer MoS2, and the energy level of the impurity states can be affected by interlayer distance, which finally disappears in bulk state when the layer distance is relatively small. Moreover, during the compressing of bilayer MoS2, the bottom layer, where S vacancy stays, gets additional charge due to interlayer charge transfer, which first increases, and then decreases due to gradually forming the interlayer S-S covalent bond, as interlayer distance decreases. The change of the additional charge is consistent with the change of the total magnetic moment of bottom layers, no magnetic moment has been found in top layer. The distribution of magnetic moment mainly concentrates on the three Mo atoms around S vacancy, each of whose magnetic moment is very much related to the Mo-Mo length. Our conclusion is that the interlayer charge transfer and S vacancy codetermine the magnetic properties of this system, which maybe a useful way to regulate the electronic and magnetic properties of MoS2 for potential applications.

Charge Engineering of Mo2C@Defect-Rich N-Doped Carbon Nanosheets for Efficient Electrocatalytic H2 Evolution

“…Because of their similar electronic structure and catalytic behaviors to Pt [12], Mo-based compounds [13,14], especially molybdenum carbide [15], have drawn tremendous fascination. On the other hand, the electronic structure significantly affects the interaction between the catalyst surface and reactants [4,[16][17][18][19][20]. Charge engineering is an important strategy to regulate the surface/interface behaviors involved in catalysis.…”

Stable Metallicity of Low Dimentional WCrC Derivatives: A First‐Principles Study

“…Simultaneously, it is difficult to control the defect sites while avoiding additional defects in reality. [12,30] On the contrary, atomic adsorption is more promising because it can easily change the coverage without introducing any additional problems.…”

“…The surface functionalization plays the key role of MXenes' electronic and magnetic properties. [10][11][12] 2D monolayer W 2 C possesses high negative Poisson's ratio, which can be used to make rare auxetic materials. [13] However, with the addition of surface functional groups such as −O, −OH, −F, the strong coupling between C-p-orbitals and W-d-orbitals in W 2 C pyramid structure is destroyed, which leads to the disappearance of the auxiliary material of W 2 C. [14] Besides, Zhou et al pointed out that Cr 2 C exhibits half-metallic ferromagnetic behavior.…”

Realistic dimension-independent approach for charged-defect calculations in semiconductors

“…However, the failure of this standard jellium model has been reported in two-dimensional (2D) semiconductors [17][18][19] . 2D materials, such as transition metal dichalcogenides, boron nitride, and phosphorene possess some intriguing physical and chemical properties, rendering them as promising candidates for future electronic and optoelectronic applications 2,4,[20][21][22] . Like bulk semiconductors, doping is a key process in these 2D materials for their device applications.…”