Band gap engineering of bulk and nanosheet SnO: an insight into the interlayer Sn–Sn lone pair interactions

Abstract

The effects of interlayer lone-pair interactions on the electronic structure of SnO are explored using density-functional theory. Our comprehensive study reveals that the band gap of SnO opens with the increase in the interlayer Sn–Sn distance. The effect is rationalized by the character of band edges which consist of bonding and anti-bonding states from interlayer lone pair interactions. The band edges for several nanosheets and strained double-layer SnO are estimated. We conclude that the double-layer SnO is a promising material for visible-light driven photocatalysts for hydrogen evolution.