Scanning Tunneling Microscopy and Quartz Crystal Microbalance Studies of Au Exposed to Sulfide , Thiocyanate , and n - Octadecanethiol
نویسنده
چکیده
Atomic resolution STM images of Au( 11 1) treated with solutions of Na2.9, H2S, or NaSCN display patterns of atoms in the shape of squares with nearest-neighbor distances of 0.27 f 0.3 nm. QCM data demonstrate that Au dissolves in aqueous solutions of sulfide and thiocyanate with 02 present. The square pattern observed is ascribed to images of Au atoms on a reconstructed Au( 11 1) surface caused by dissolution of Au by sulfide or thiocyanate. n-Octadecanethiol/Au( 1 1 1) surfaces damaged by the STM tip display a similar square pattern, indicating removal of Au atoms by the tip in a manner analogous to the dissolution process observed for sulfide or thiocyanate.
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