Quantitative analysis of the functionalization of gallium phosphide with organic azides.

Gallium phosphide (GaP) surfaces were functionalized with two different molecules that contain an azide moiety at their terminus. Compound 4-azidophenacyl bromide (4AB) is an aryl azide with a bromine group at its opposite terminus that provides easy identification of the molecule's presence on the surface with x-ray photoelectron spectroscopy (XPS). O-(2-aminoethyl)-O'-(2-azidoethyl)pentaethylene glycol (AAP) is a small poly(ethylene glycol) molecule with an amine group at its opposite terminus.