Non‐Random Island Nucleation in the Electrochemical Roughening on Pt(111)

Many chemical surface systems develop ordered nano-islands during repeated reaction and restoration. Platinum is used in electrochemical energy applications, like fuel cells electrolysers, although it scarce, expensive, degrades. During oxidation-reduction cycles, simulating device operation, nucleation growth of occurs that eventually enhances the dissolution. Preventing would be most effective solution. However, little known about atomic details nucleation; a process almost impossible to observe. Here, we analyze nuclei-distance distribution mapping out underlying mechanism: rarely observed, non-random takes place. Special, preferential sites priori do not exist, initially via precursor form semi-ordered Pt-oxide structure. This mechanism seems general, possibly explaining also nano-island formation on other surfaces/reactions.