Effects of torsional control on the optical and electronic properties of monolayer NbS2: A first-principles study

Abstract

Based on the first principle calculation, the torsional deformation control of single-layer graphene transition metal disulfide NbS 2 at different angles is systematically studied in this paper. The electronic properties include the energy gap change of the electronic band structure, the composition of the density of States, the trends of the real and imaginary parts of the dielectric function, and the electronic and optical properties such as absorption and reflection spectra. Our analysis shows that distortion can change the bond length of NbS 2 . Under torsion, the initial key length is 2.492 A, the shortest is 2.240 A, and the longest extended key is 2.744 A. On the other hand, the study of electronic and optical properties shows that the band structure of NbS 2 will have a split band gap at the Fermi level. When the torsion angle is 12 °, we notice that the electronic and optical properties of NbS 2 will change significantly, the energy band spacing will increase, and the corresponding minimum particle number will decrease significantly. The optical properties show that the torsion system can improve the storage capacity and polarizability of the material, improve the local optical response, and strongly impact the properties of the ultraviolet region. At the same time, it can improve the optical response to visible light and photocatalytic activity and effectively improve the transmittance of the material itself.