✦ LIBER ✦

Mechanism and kinetics of passivation of cadmium and zinc in alkaline solutions

✍ Scribed by M.A.V. Devanathan; S. Lakshmanan

Publisher: Elsevier Science
Year: 1968
Tongue: English
Weight: 750 KB
Volume: 13
Category: Article
ISSN: 0013-4686
DOI: 10.1016/0013-4686(68)85002-9

No coin nor oath required. For personal study only.

✦ Synopsis

The passivation of cadmium and cadmium amalgam in alkaline solutions has been studied by the galvanostatic transient technique. The dependence of ir w on i at low current densities and constancy at high current densities observed fits well with the theoretical relationship derived by Reddy, Devanathan and Bockris. The results are analysed with reference to the dissolution-precipitation mechanism in which the passivating step is the formation of an electronically conducting monolayer of oxide. A mechanism for the passivation of cadmium is proposed, the active intermediate being CdOH+ ion. The results of Kaesche have been interpreted to show that a similar mechanism holds good for the passivation of zinc, the probable intermediate species being ZnOH+ ion. The recent criticisms by Fleischmann et nl. of the dissolution-precipitation model based on potentiostatic experiments are shown to be unfounded.

📜 SIMILAR VOLUMES

On the mechanism of passivation of the c

On the mechanism of passivation of the cadmium electrode in alkaline solutions

✍ A.A. Abdul Azim; K.M. El-Sobki 📂 Article 📅 1972 🏛 Elsevier Science 🌐 English ⚖ 493 KB

The electrochemical behaviour of the Cd electrode in O-1-6 N NaOH has been investigated. Both the potentiostatic and galvanostatic techniques were employed. It has been shown that the electrode surface is primarily covered with a porous layer of Cd(OH), which is precipitated from the solution. Above

Breakdown of cadmium passivity in alkali

Breakdown of cadmium passivity in alkaline solution

✍ Prof. Dr. S. S. Abd El-Rehim; O. Abou El-Wafa; S. M. Abd El-Wahab; S. M. Rashwan 📂 Article 📅 1992 🏛 John Wiley and Sons 🌐 German ⚖ 501 KB

## Abstract The electrochemical behaviour of a Cd anode was investigated in 0.05–2 M NaOH solutions by the potentiodynamic technique. The polarization curves exhibit active to passive transition prior to oxygen evolution. The threshold potential of the active dissolution is very close to the revers

Kinetics and mechanism of passivation of

Kinetics and mechanism of passivation of steel in sodium phosphate solutions

✍ V.S. Muralidharan; K.S. Rajagopalan 📂 Article 📅 1978 🏛 Elsevier Science 🌐 English ⚖ 254 KB

This paper reports that three current peaks are observed during psssfvabnn ofsteelln NaH,P0, solutions in the pH range of 3 to 5. These are identified as peaks due to growth of phosphate film on theiron surface resulting in passivation of the metal surface, By comparison with anodic oxidation o( sil

Dissolution and passivation of vertical

Dissolution and passivation of vertical porous zinc electrodes in alkaline solution

✍ M.W. Breiter 📂 Article 📅 1970 🏛 Elsevier Science 🌐 English ⚖ 668 KB

The anodic dissolution and passivation of vertical porous zinc electrodes that were prepared by pressing zinc powder or amalgamated zinc powder into small disks were studied in 6 M KOH + O-25 M ZnO by measuring potentiostatic current/potential curves at a rate of 1 mV/s and by taking photomicrograph

Passivity and passivity breakdown of zin

Passivity and passivity breakdown of zinc anode in alkaline medium

✍ Prof. Dr. S. S. Abd El Rehim; S. M. Abd El Wahab; E. E. Fouad; Hamdy H. Hassan 📂 Article 📅 1995 🏛 John Wiley and Sons 🌐 German ⚖ 562 KB

## Abstract The electrochemical behaviour of zinc in NaOH solutions has been investigated by using potentiodynamic technique and complemented by X‐ray analysis. The E/i curves exhibit active, passive and transpassive regions prior to oxygen evolution. The active region displays two anodic peaks. Th

Effect of arsenate anion on the dissolut

Effect of arsenate anion on the dissolution and passivation of zinc electrode in slightly alkaline solutions

✍ I. Sánchez de Pinto; C.P. De Pauli; H. Herrera; H. Mishima; B.A. López 📂 Article 📅 1986 🏛 Elsevier Science 🌐 English ⚖ 563 KB

Zinc dissolution and passivation in either arsenate or borate and a mixture of arsenate-borate solutions at pH 8.9 was studied by polarization curves and cyclic voltammetry. The arsenate anion produces an increase on zinc dissolution . Potential sweep rate, rotation speed, temperature, dissolved oxy