Chemical functionalization of silicene

Silicene exhibits extraordinary physical properties especially Dirac fermion characteristics. However, the zero-gap band structure of silicene hinders its applications in nanoelectronic and optoelectronic devices. It is thus desirable to open a finite band gap in silicene. Chemical functionalization is a commonly used method to tailor the structures and electronic properties of two-dimensional materials. In this paper we review the recent 3-year progress of silicene, including its hydrogenation, oxidization, halogenation, and other methods to modify silicene.