Self-Assembled Monolayers of Substituted Phenylthiourea on Au

Self-assembled monolayers(SAMs) of p methylphenylthiourea, p-chlorophenylthiourea and2, 4, 6-trlbromophenylthiourea on gold were prepared and characterized by contact angle measurement, ellipsometry, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy(AFM). Results suggest that Au-S bond formed by the S atoms of substituted phenylthioureamolecules with the Au atoms on gold surface, which induce molecules to form the orientedpacked monolayer. Some defect observed for monolayers may by caused formation of by the defect of gold surface and the reversibility of the absorption.