The Self-assembly of Heterocyclic Selenium Compounds (4,5-Benzopiaselenol) on Gold

To find a new system of self-assembled monolayers (SAMs) and to build up new founctions, the SAMs of heterocyclic selenium compounds (piaselenol, with macrocyclic conjugated plane molecule structure) on gold surface were investigated. The SAMs of piaselenol were characterized by X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry. The results of XPS showed that the binding energy of Se3d changed from57.4 eV to 57.1 eV, which proved that the gold surface had been assembled with piaselenol molecules. The results of cyclic voltammetry showed that the peaks of the oxidation and reduction of Fe(CN)63-/4-almost disappeared after the self-assembly. The reduction peak potential of the self-assembled piaselenol on gold was -0.66 V in the Na2B4O7solution, which was close to the potential of bare gold in piaselenol solution. The electron transfer mechanism about SAMs of organoselenium compounds on the gold surface was also discussed.