Adsorption rotating ring—disc electrode

The electrosorption valency usually increases as the underpotential decreases to approach the ionic charge (total discharge of the cation) close to the Nernst potential, for instance in the case of lead and thallium upd on silver [114]. However, the co-adsorption of anions may contribute to the observed apparent electrosorption valence, as rotating ring disc electrode (RDE) experiments have shown [113]. 

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