Control of two-dimensional structure of tolanethioacetate self-assembled monolayers on Au(111)

摘要

Nanometer-scale structure and binding condition of tolanethioacetate (TTA) self-assembled monolayers (SAMs) formed in various solutions on Au(111) were investigated by scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). STM imaging revealed that two-dimensional (213) ordered TTA SAMs with an overlayer structure of (root 13 x root 5)R24 degrees on Au(111) were formed in a polar protic solvent, while TTA SAMs with disordered phases were formed in a polar aprotic solvent and a nonpolar solvent. In addition, XPS measurements showed that the XPS spectra for TTA SAMs formed in a nonpolar solvent were markedly different from those formed in a polar protic solvent, indicating that the binding condition of TTA SAMs was influenced by the solvent properties. In this study, We found that 2D ordered TTA SAMs on Au(111) can be obtained by controlling the properties of solvents, in particular, by using a polar protic solvent. (C) 2007 Elsevier B.V. All rights reserved.