Theoretical perspective on the electronic structure and optoelectronic properties of type-II SiC/CrS2 van der Waals heterostructure with high carrier mobilities

Abstract Two-dimensional heterostructures formed by stacking layered materials play a significant role in condensed matter physics and materials science due to their potential applications in high-efficiency nanoelectronic and optoelectronic devices. In this paper, the structural, electronic, and optical properties of SiC/CrS 2 van der Waals heterostructure (vdWHs) have been investigated by means of density functional theory calculations. It is confirmed that the SiC/CrS 2 vdWHs is energetically and thermodynamically stable indicating its great promise for experimental realization. We find that the SiC/CrS 2 vdWHs has a direct-band gap and type-II (staggered) band alignment, which can effectively separate the photo-induced electrons and holes pairs and extend their life time. The carrier mobilities of electrons and holes along the armchair and zigzag directions are as high as 6.621 × 10 3 and 6.182 × 10 4 cm 2 V −1 s −1 , respectively. Besides, the charge difference and potential drop across the interface can induce a large built-in electric field across the heterojunction, which will further hinder the electron and hole recombination. The SiC/CrS 2 vdWHs has enhanced optical absorption capability compared to individual monolayers. This study demonstrates that the SiC/CrS 2 vdWHs is a good candidate for application in the nanoelectronic and optoelectronic devices.