AVS 51st International Symposium
    Surface Science Tuesday Sessions
       Session SS2-TuM

Paper SS2-TuM10
Sulfur-induced Nano-restructuring of the Au(111) Surface: A Real-time STM Study

Tuesday, November 16, 2004, 11:20 am, Room 210C

Session: Self Assembled Monolayers
Presenter: M.M. Biener, Harvard University
Authors: M.M. Biener, Harvard University
J. Biener, Lawrence Livermore National Laboratory
D. Pinnaduwage, Harvard University
C.M. Friend, Harvard University
Correspondent: Click to Email
The interaction of sulphur with gold surfaces has attracted considerable interest due to numerous technological applications such as the formation of self-assembled monolayers (SAMs), corrosion inhibition, and sensors. In this work, the interaction of sulfur with Au(111) was studied by real-time scanning tunnelling microscopy (STM) using sulfur dioxide as a source of sulfur. A small fraction of the impinging sulfur dioxide molecules deposit sulphur on the surface. Up to a coverage of ~0.3 ML sulfur forms an ordered adlayer. With further increasing S coverage we observe the formation of a two-dimensional AuS overlayer exhibiting short range order. Gold atoms are removed from the surface and are incorporated into the growing gold sulfide resulting in pit formation. This gold sulfide layer is stable up to ~500 K where it develops long-range order and exhibits a complex Low Energy Electron Diffraction (LEED) pattern. We will present nano-scale, time-resolved movies capturing the sulphur induced restructuring of the Au(111) surface.