Place exchange mechanism

The authors were also the first to postulate the existence of a place-exchange mechanism at Pt, suggesting that the path of oxide formation is ... 

Figure 2 indicates the growth of the oxide once the initial monolayer or two have been formed by the place-exchange mechanism. The oxide separates the parent metal from the oxygen, so that transport of metal... 

The intrinsic irreversibility probably results from some kind of phase transformation such as the transformation of the adsorbed layer into a surface phase oxide by a place exchange mechanism. This may lead to different reaction paths for the anodic and cathodic processes. 

High sweep rate cathodic voltammograms (> 1 V/sec), particularly in concentrated acids and at lower temperatures, provide additional evidence of various states of adsorbed oxygen species. Angerstein-Kozlowska et have postulated that the less reversible adsorbed oxygen species is formed from Pt20H and PtOH by a place exchange mechanism ... 

The overall problem of the nonsteady-state passive iron has been reexamined with the purpose of reaching a consistent interpretation of the empirical equation firmly esfablished in acidic [135] and neutral [133,134] media and also for nickel in acidic solutions [135] in classical papers. As stated earlier [141], this equation contradicts the high-field mechanism because it predicts a direct logarithmic Q t) relationship consistent with a place exchange mechanism, whereas the high field should generate an inverse logarithmic dependence [4]. 

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