Selective attachment of 4-bromostyrene on the Si(111)-(7 × 7) surface

Abstract

The covalent attachment of 4-bromostyrene on the Si(111)-(7 × 7) surface was investigated using X-ray photoelectron spectroscopy (XPS), high-resolution electron energy loss spectroscopy (HREELS), and density functional theory calculations. The HREELS spectra suggest that 4-bromostyrene covalently binds to the silicon surface through a [2 + 2]-like cycloaddition pathway between the external vinyl group and the adjacent adatom-rest atom pair of the Si(111)-(7 × 7) surface, forming 4-bromoethylbenzene-like binding configuration. The XPS results further confirm that only the vinyl double bond participates in the surface binding reaction, whereas the bromine atom remains unchanged during the adsorption process. The resulting 4-bromoethylbenzene-like structure on the Si(111)-(7 × 7) surface can be employed as a precursor for further chemical modification and functionalization. © 2011 American Chemical Society.