Band gap engineering of GaN nanowires by surface functionalization.

We investigated [0001] bare and functionalized gallium nitride (GaN) nanowires by using the density-functional theory. Passivation of GaN nanowires with various functional groups (H, NH₂, OH, and SH) show distinct electronic properties. We found that the band gap for the nanowires with partial surface coverage is dependent on the coverage ratio and adsorption sites. In view of the importance of surface states to the properties of nanowires, we suggest that the electronic and optical properties can be modulated by controlling the surface states of nanowires by functionalization. [ABSTRACT FROM AUTHOR]