Tunable electronic properties of GaS–SnS2 heterostructure by strain and electric field

Vertically stacked heterostructures have received extensive attention because of their tunable electronic structures and outstanding optical properties. In this work, we study the structural, electronic, and optical properties of vertically stacked GaS–SnS 2 heterostructure under the frame of density functional theory. We find that the stacked GaS–SnS 2 heterostructure is a semiconductor with a suitable indirect band gap of 1.82 eV, exhibiting a type-II band alignment for easily separating the photo-generated carriers. The electronic properties of GaS–SnS 2 heterostructure can be effectively tuned by an external strain and electric field. The optical absorption of GaS–SnS 2 heterostructure is more enhanced than those of the GaS monolayer and SnS 2 monolayer in the visible light region. Our results suggest that the GaS–SnS 2 heterostructure is a promising candidate for the photocatalyst and photoelectronic devices in the visible light region.