First-principles study on the electronic structure and photocatalytic property of a novel two-dimensional ZrS₂/InSe heterojunction

Abstract

Photocatalytic water cracking technology provides a broad prospect for solving the current energy crisis using solar energy and water resources. In this paper, a two-dimensional ZrS₂/InSe heterojunction for accelerating the process of hydrogen production from water decomposition was constructed, and its electronic structure and photocatalytic property were studied using first-principles calculation. The results show that the lattice mismatch rate of the heterojunction from monolayer ZrS₂ and monolayer InSe is 2.48%, and its binding energy is -1.696 eV, indicating that the structure of the heterojunction is stable. The ZrS₂/InSe heterojunction is an indirect bandgap with a bandgap value of 1.41 eV and a typical type-II band arrangement. Importantly, the ZrS₂/InSe heterostructure has a Z-scheme structure, which is beneficial to the separation of photogenerated electron hole pairs. Moreover, the ZrS₂/InSe heterojunction has a strong absorption ability for visible light (up to 3.84 × 10⁵ cm^-1), which is helpful for improving its photocatalytic efficiency. The two-dimensional ZrS₂/InSe heterojunction is a very promising photocatalyst, as concluded from the above studies.