Surface microscopic structure and electrochemical rectification of a branched alkanethiol self-assembled monolayer

J Phys Chem B. 2006 Jan 26;110(3):1102-6. doi: 10.1021/jp056356k.

Abstract

The tert-butanethiol self-assembled monolayers (SAMs) on Au(111) surfaces were prepared from various solvents and investigated by a combination of scanning tunneling microscopy (STM) and electrochemistry in aqueous environments. High-resolution STM images reveal a (radical(7) x radical(7))R19 degrees surface lattice structure, in contrast with the conventional lattice (radical(3) x radical(3))R30 degrees structure for straight-chain alkanethiol SAMs. Interestingly, such a branched monolayer shows electrochemical rectification toward redox probes. We suggest that electrochemical rectification could be a general characteristic of short-chain branched alkanthiol SAMs, and originate in localized electronic effects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electrochemistry
  • Gold / chemistry
  • Membranes, Artificial*
  • Microscopy, Scanning Tunneling / methods
  • Particle Size
  • Sensitivity and Specificity
  • Sulfhydryl Compounds / chemistry*
  • Surface Properties
  • Water / chemistry

Substances

  • Membranes, Artificial
  • Sulfhydryl Compounds
  • Water
  • propanethiol
  • Gold
  • n-butyl mercaptan