Theoretical investigation on the electronic structure of new InSe/CrS2 van der Waals heterostructure

Atomically thin, two-dimensional (2D) indium selenide (InSe) is a new graphene-like semiconducting material which has gained significant attention due to the large tunability in the bandgap (from 1.4 to 2.6 eV) and high carrier mobility. Constructing InSe-based van der Waals heterostructure (vdWH) is a potential way to achieve more desirable properties and further extend the application of InSe. Herein, we firstly demonstrate the electronic and optical properties of the InSe/CrS2 vdWH by using first-principles calculation. Our results suggest that this heterostructure has an intrinsic mixing band alignment with the bandgap of 1.20 eV, which shows a good light absorption in visible light region. Meanwhile, an intrinsic mixing band alignment can be transformed between type-I and type-II. Moreover, the bandgap values can be tuned by applying electric field. These results indicate that the flexible InSe/CrS2 vdWH can provide new ways to utilize 2D materials in future optoelectronic devices.