SOME SPECIFIC POTENTIODYNAMIC FEATURES OF NICKEL ELECTRODES IN ALKALINE AQUEOUS-MEDIA

It has been pointed out that the potentiodynamic behaviour of nickel electrode is very similar to, and its voltammograms closely resemble, the ones scanned on palladium in alkaline aqueous media, just in accordance with their positions in the periodic table. It has also been shown that in common with Pd and Au, the 'hump' within the reversal scan following after hydrogen evolution, corresponds to and correlates with the mutual adsorption and adsorption peaks (H-adatoms and H-abatoms), and in its essence represents the diffusional desorption peak for hydrogen in its backwards mass-transport and deliberation from the nickel lattice. In common with Pd and Rh, two type of oxides grow upon nickel surfaces during the anodic scans: the monolayer alpha- and pronounced multilayer beta-phase. For the first time, the irreversible peak of monolayer alpha-oxide desorption on Ni voltammograms has been marked.