Prepared by Spontaneous Ru Deposition

It was recently reported31 that deposited Ru islands play a significant role in promoting the electrocatalytic activity of Au(lll) towards formaldehyde oxidation in sulfuric acid media. Cyclic voltammo-grams of the electrochemical oxidation of formaldehyde on Au( 111) 

There was no HCHO oxidation on the Ru/Au(lll) electrode up to a potential of 0.25 V Starting from a potential of 0.25 V, the reaction occurred with increasing current up to a potential of 0.55 V, showing a peak with a maximum current density of 0.07 mA/cm2 at a potential of 0.43 V At higher potentials, as well as in the reverse sweep, the HCHO oxidation occurred following the same path as on the pure Au(l 11) surface, although with smaller currents, most likely due to the inhibiting effect of the present oxidized Ru species. 

For comparison, the anodic sweeps of HCHO oxidation on Ru/Au(l 11) (from Fig. 21) and on pure Au(l 11) in the same solution are presented in Fig. 22 by a solid line and by a dotted line, respectively. 

CO stripping voltammetry measurements were performed using Ru/Pt(lll), prepared by spontaneous Ru deposition. A typical CV curve for CO stripping on Ru/Pt(lll), showing a clear split in the 

CO stripping profile, is presented in Fig. 24. It is well known that the first CO oxidation peak on Ru/Pt( 111) originates from CO oxidation on the Ru adislands.61 Indeed, previous XPS results demonstrated that Ru showed oxide formation already at 0.12 V28 

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