Surface Extended X-Ray Absorption Fine Structure of Underpotentially Deposited Silver on Au(111) Electrodes

摘要

The fluorescence detected surface EXAFS of silver, underpotentially deposited from aqueous solutions of silver ion (HCIO4 electrolyte) on Au(111) electrodes was used to investigate the local structure of the adsorbate. Analysis of the data indicates that the silver atoms are bonded to three surface gold atoms at a distance of 2.75 + or - 0.05 A and to an oxygen atom (from solvent of electrolyte) at a distance of 2.42 + or - 0.05 A. These data suggest that the silver atoms sit at 3-fold sites on the gold surface with water or perchlorate anion (from the electrolyte) bonded at a well-defined distance. Reprints. (JHD)