Janus Ga2SeTe/In2SSe heterostructures: tunable electronic, optical, and photocatalytic properties

Heng-Fu Lin; Hui-Ying Liu; Min Wang; Shu-Shen Wang; Ting-Ping Hou; Kai-Ming Wu

doi:10.1039/d1cp04413c

Janus Ga₂SeTe/In₂SSe heterostructures: tunable electronic, optical, and photocatalytic properties

Phys Chem Chem Phys. 2022 Feb 16;24(7):4425-4436. doi: 10.1039/d1cp04413c.

Authors

Heng-Fu Lin^{1

2}, Hui-Ying Liu¹, Min Wang², Shu-Shen Wang^{1

2}, Ting-Ping Hou^{1

2}, Kai-Ming Wu^{1

2}

Affiliations

¹ Hubei Province Key Laboratory of Systems Science in Metallurgical Process, and College of Science, Wuhan University of Science and Technology, Wuhan 430081, China. hflin@wust.edu.cn.
² The State Key Laboratory for Refractory Material and Metallurgy, International Research Institute for Steel Technology, and Collaborative Centre on Advanced Steels, Wuhan University of Science and Technology, Wuhan 430081, China.

PMID: 35113108
DOI: 10.1039/d1cp04413c

Abstract

Vertically stacking two-dimensional materials into van der Waals (vdW) heterostructures (HS) is deemed to be an effective strategy to tailor their physical properties and enrich their applications in modern nanoelectronics. Here, we study the geometry, electronic, and optical properties of Janus Ga₂SeTe/In₂SSe heterostructures by using first-principles calculations. We consider four models of Ga₂SeTe/In₂SSe heterostructures with an alternative chalcogen atom layer sequence and five potential stacking configurations, and find that the most energy favorable stacking pattern is AB stacking for each model. The heterostructures form type II alignment with a direct band gap. Moreover, the band gap values are highly dependent on the magnitude of the electric dipole, which is related to the sublayer intrinsic dipole direction and interface charge transfer. Additionally, the optical absorption of the heterostructures is intensified in the visible and ultraviolet regime. Furthermore, we predict two heterostructures with the band edge straddling the water redox potential level. These findings can help in understanding the tailored properties of the heterostructures based on Janus two-dimensional materials, and guide experiments in designing novel optoelectronic devices.