Adsorption of Zn atoms by monolayer WS doped with different atoms X (X = O, Se, N, P, F, Cl): first principles study.

Context: The effect of X (X = O, Se, N, P, F, Cl) doping on the adsorption of Zn atoms by WS was investigated based on first principles. The electronic structure and optical properties of the adsorbed system after atomic doping were calculated. It is found that the Zn atom adsorbed on the W top (T) site has the most stable structure.

Effect of compressive strain on electronic and optical properties of Cr-doped monolayer WS.

Context: The electronic properties and optical properties of Cr-doped monolayer WS under uniaxial compressive deformation have been investigated based on density functional theory. In terms of electronic structure properties, both intrinsic and doped system bandgaps decrease with the increase of compression deformation, and the values of the bandgap under the same compression deformation after Cr doping are reduced compared with the corresponding intrinsic states. When the compressive deformation reaches 10%, both the intrinsic and doped system band gaps are close to zero.

First principle study of the effect of doping on the optoelectronic properties of Cr-adsorbed MoS.

Context: This study explores, for the first time, using first principles, the impact of substitutional doping with boron (B), carbon (C), and nitrogen (N) on the adsorption of chromium (Cr) on monolayer MoS. The effects of doping on the Cr adsorption behavior of MoS were investigated using four MoS systems, namely, pure, boron (B)-doped, carbon (C)-doped, and nitrogen (N)-doped, in order to gain an in-depth understanding of the mechanism of the effects of doping on the electronic structure and optical properties of Cr adsorbed by MoS, to optimize the properties of MoS, to explore new areas of application, and to promote the development of materials science. Four MoS adsorption systems of Cr adsorption on pure, B-doped, C-doped, and N-doped MoS were optimized, and the optimized results showed that the stable adsorption location of Cr on both pure and doped MoS was the hollow location at the top of the folded hexagon.

Effect of O-doping on electronic and optical properties of monolayer MoSe under shear deformation.

Context: In this study, the electronic structures and optical properties of the pure MoSe and O-doped MoSe systems under different shear deformations are calculated based on the first-principles approach. It is hoped to provide new possibilities for the design of novel controllable optoelectronic devices and to provide guidance for the application of MoSe in the field of optoelectronic devices. The findings indicate that both pure MoSe and O-doped MoSe systems are somewhat impacted by shear deformation.

First-principles study of the effect of doping on the optoelectronic properties of defective monolayers of MoSe.

Context: In this paper, the structural stability, electronic structure, and optical properties of monolayer MoSe doped with C, O, Si, S, and Te atoms, respectively, under defective conditions are investigated based on first principles. It is found that the system is more structurally stable when defecting a single Se atom as compared to defecting a single Mo or two Se atoms. The electronic structure analysis of the system reveals that intrinsic MoSe is a direct bandgap semiconductor.

First-principles study on the mechanical properties of cement mortar modified with functionalized graphene oxide.

Context: In this paper, first-principle calculations reveal that the shear strength of the graphene-cementitious interface (G/C-S-H) (12 MPa) is lower than that of the epoxy, hydroxyl and carboxyl graphene-cementitious interfaces (G-O/C-S-H, G-OH/C-S-H and G-COOH/C-S-H) (21 MPa, 29 MPa and 14 MPa). This indicates that the introduction of functional groups helps to improve the mechanical properties of the graphene-cementitious contact interface. Electrical analysis of the interface reveals that functional groups adsorbed on graphene change the electron distribution on the graphene surface.