The treatment of Ag, Pd, Au and Pt electrodes with OH • radicals reveals information on the nature of the electrocatalytic centers

Abstract

The treatment of Ag, Pd, Au and Pt electrodes with OH • radicals can be used to get information on the nature of the electrocatalytic sites. Atomic force microscopy (AFM) measurements, various electrochemical techniques, and chemical solution analysis show a more or less effective surface dissolution of these metals upon OH • treatment. The effect of the surface alterations on the electrocatalytic activity with respect to the quinone/hydroquinone system revealed distinct differences between Ag and Au (previous studies) on one side, and Pt and Pd on the other side. Whereas, in case of Pt and Pd, the electrocatalytic properties are obviously related to the regular surface atoms, in case of Ag and Au the active centers are highly reactive surface atoms which can be removed by OH • radicals. © 2011 The Author(s).