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

It has been pointed out that the potentiodynamic behaviour of nickel e lectrode is very similar to, and its voltammograms closely resemble, t he ones scanned on palladium in alkaline aqueous media, just in accord ance with their positions in the periodic table. It has also been show n that in common with Pd and Au, the 'hump' within the reversal scan f ollowing 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 hydr ogen 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 m onolayer alpha-oxide desorption on Ni voltammograms has been marked.