Chemical Engineering of Silicon with Functional Molecules

This paper discusses some strategies to covalently anchor functional molecules on Si(100) in order to introduce onto a solid surface specific functionalities. Two main typologies of synthetic routes both based on the hydrosilylation reaction are described. First approach, which consists on the direct hydrosilylation of the functional molecule on the H-terminated Si surface, is suited for the anchoring of robust cavitand molecules. These organic receptors keep their molecular recognition properties after grafting, thus functionalized surfaces have various applications ranging from sensing to surface nanoassembly. Second approach, which is based on multistep anchoring routes, has been adopted for magnetic and luminescent inorganic complexes (Single Molecular Magnets and europium -diketonates) which cannot withstand direct hydrosilylation reaction. For both approaches, the grafting of mixed monolayers, in which inert spacers dilute the functional molecules, improves surface packing and allows the control of surface concentration and orientation of the active functionalities.