| AVS 55th International Symposium & Exhibition | |
| Nanometer-scale Science and Technology | Wednesday Sessions |
| Session NS+NC-WeM |
| Session: | Characterization and Imaging of Nanostructures |
| Presenter: | E.V. Iski, Tufts University |
| Authors: | E.V. Iski, Tufts University M. El-Kouedi, Tufts University D.O. Bellisario, Tufts University E.C.H. Sykes, Tufts University |
| Correspondent: | Click to Email |
Underpotential deposition (UPD) is a useful way of depositing up to one monolayer of a metal onto a more noble metal. We used this technique to deposit Ag onto Au(111) with and without the presence of chloride. Electrochemical scanning tunneling microscopy (EC-STM) revealed that, depending on the sample potential and hence the surface Ag coverage, Ag grows in a variety of ordered structures that can be atomically resolved. However, upon being removed from the electrochemical cell, these “chloride-free” Ag monolayers are subject to degradation by air. Interestingly, if the Ag layer is formed in the presence of trace amounts of chloride, the resulting AgCl layer is stable both in air and even at temperatures as high as 1000 K. X-ray photoelectron spectroscopy (XPS) was used to quantify the stoichiometry of the systems and both ambient- and EC-STM revealed that even after exposure to extreme temperatures the monolayer thick AgCl layer remained atomically perfect.