Monolayer of Hydrazine Facilitates the Direct Covalent Attachment of C60 Fullerene to a Silicon Surface

The development of oxygen-free organic-inorganic interfaces has led to new schemes for the functionalization of silicon surfaces with nitrogen-based chemical groups. However, building layers of large structures directly on this functionalized surface has remained elusive. This work confirms the path to form a stable interface between silicon and buckminsterfullerene C-60 based on covalent chemical bonds. The starting point for this modification is the hydrazine-reacted Si(111) surface with the diamine functionality, which is further reacted directly with the C-60 molecules. The chemistry of this process is confirmed spectroscopically and microscopically and can be used to form organic-inorganic interfaces separated by a single layer of nitrogen.