The kinetics and mechanism of the nickel electrode—III. The potentiodynamic response of nickel electrodes in alkaline solutions in the potential region of Ni(OH)2 formation

Abstract

The electrochemical behaviour of nickel in alkaline aqueous solutions within the anodic potential range yielding Ni(OHh and under different potentiodynamic perturbations profiles has been investigated. The formation of Ni(OHh is characterized by an irreversible anodic current peak which is quantitatively interpreted in terms of a complex reaction pathway involving different hydroxoadsorbed slx.~cies.

Spectroscopic And Electrochemical Studies Of Electrochromic Hydrated Nickel Oxide Films

“…Also, an oxygen-evolution peak occurs at about 550 m V (SCE). Similar results have been noted by other investigators (18)(19)(20). The oxidation reaction taking place at the anodic peak has been identified as Ni(OH)2 -+ NiOOH + H+ + e-.…”

Electrochemical Formation of a Failure Preventing Film on Nickel Surface in Borate Solutions

“…Furthermore, x-ray photoelectron spectroscopy [32] indicates that the film present on the electrode surface is composed of NiO and b-Ni(OH) 2 . The previous work shows also that b-Ni(OH) 2 cannot be reduced to Ni even in the H 2 evolution region [12][13][14]33]. Therefore, no cathodic reduction peaks are observed in the present study, curves CV 3 and CV 4 , in Fig.…”

“…9, an ill-defined cathodic reduction peak, C 1 , starts to appear on reversal polarization. One is bound here to conclude that the nickel oxides, which are formed in the passive region, A 2 , namely b-Ni(OH) 2 is transformed into an easily reducible anodic reaction species as the potential increases in the anodic direction [12][13][14]33]. The latter anodic species is likely to be b-NiOOH, which is reduced when the potential scan is reversed at potential between ?0.70 V (SCE) and the oxygen evolution potential.…”

“…9. On the other hand, Schrebler Guzman et al [33] reported that Ni(OH) 2 appears as a hydrated species on the metal surface once its solubility product is exceeded. However, in aqueous solutions, Ni(OH) 2 is bound to the following well known equilibria in solution [33]:…”

Aqueous corrosion behaviour of Fe–Ni–B metal glasses

“…Therefore, Ni oxidation has progressed up to the Ni 3+ state. ␤NiOOH is the most stable Ni-hydroxide [17]. The (Ni,Fe)(OH) 2 layer does not contribute much to passivity, due to its low thickness (few monolayers) in all types of electrolytes [13,17].…”