Interfacial configuration and interfacial regulation of electronic properties of MoS2 heterophase junctions

Abstract

The transition of 1H-transition metal dichalcogenides (TMDCs) to 1H-1T’ heterophase junction can be induced by alkali metal ion intercalation, laser irradiation, electric-field-induced etc, but the interfacial configuration is complex and the effect of the interface on the properties of TMDCs heterophase junction is not well known. Herein, we propose two kinds of interface models, namely, steep interface and gradient interface. The properties of 1H–MoS2 and 1T′-MoS2 phases are well preserved in the steep interface model due to clean atomic interface. In the gradient interface model, the interface configuration is relatively complex, but we find that the defects at the interface can release the local strain to improve the stability of the system. Interestingly, it is found that the 1H-1T’ MoS2 heterophase junction with higher intensity of density of state at the Fermi level (N(EF)) is more stable among the gradient interface model. Finally, it is found that the atoms in the interface of 1H-1T’ MoS2 heterophase junction have the largest out-of-plane deformation due to lattice mismatch regardless of the steep interface model or the gradient interface model, and the key factor affecting the electronic properties of the 1H-1T’ MoS2 heterophase junction is the electronic states of the atoms at the interface. We believe that our research provides a theoretical scheme for the interface regulation to achieve the application of 1H-1T’ heterophase junction based on TMDCs.