Electrolytic Behavior of Nickel in Polarization by Variable Asymmetric Rectangular Current in Alkaline Solutions

2020 ◽  
Vol 299 ◽  
pp. 1010-1016
Author(s):  
V.V. Demiyan ◽  
E.A. Zelenskaya ◽  
N.P. Shabelskaya

The paper presents experimental data on nickel oxidation during electrolysis under rectangular alternating current in alkaline solutions, when the cathode pulse (Iк ) is greater than the anode pulse ( Iа ). During the process, intense nickel destruction occurs forming bivalent oxide powder. Under prolonged electrolysis, this powder deposits at the bottom of the electrolyzer in the form of a sponge. The results obtained can be used to produce active mass in the porous nickel oxide electrode of a chemical current source.

2018 ◽  
Author(s):  
I. A. Dhole ◽  
Y. H. Navale ◽  
Y. M. Jadhav ◽  
R. N. Mulik ◽  
S. G. Pawar ◽  
...  

1959 ◽  
Vol 37 (1) ◽  
pp. 292-307 ◽  
Author(s):  
B. E. Conway ◽  
P. L. Bourgault

The nickel – nickel oxide electrode forms the positive plate in the charged nickel–cadmium battery. After "charging" the electrode to a chemical state represented by the non-structural formula NiOx, where x can vary from about 1.4 to 1.8 depending on the current density and temperature, loss of oxygen and a fall of potential on open circuit occurs. In the present work this "self-discharge" effect has been examined by study of (i) the rate of decay of e.m.f. on open circuit, (ii) rate of oxygen evolution on open circuit, (iii) the electrochemical capacity of the electrode, and (iv) the build-up or charging curves for the electrode. The decay behavior has been studied in aqueous KOH solutions from 0.0015 to 15 M. Tafel slopes are obtained from the plots of e.m.f. vs. log (time of decay), and abrupt changes occur at certain electrode potentials which indicate changes of rate-determining mechanism in the self-discharge process. The slopes observed are interpreted in terms of a new scheme of consecutive reactions for anodic oxygen evolution by deducing, by means of the Christiansen method, the relevant Tafel slopes. It is shown that the scheme proposed uniquely accounts for the experimental behavior and that the change of mechanism observed in the self-discharge can only be explained if two consecutive and not alternative processes are involved. The dependence of the rates of self-discharge upon OH− ion and water activity is deduced and the significance of these results is discussed.


1955 ◽  
Vol 51 ◽  
pp. 1433 ◽  
Author(s):  
G. W. D. Briggs ◽  
Elizabeth Jones ◽  
W. F. K. Wynne-Jones

1962 ◽  
Vol 40 (10) ◽  
pp. 1933-1942 ◽  
Author(s):  
B. E. Conway ◽  
E. Gileadi

Electrochemical kinetic studies have been carried out at the nickel oxide electrode showing that the reversible potential for the NiII–NiIII system is independent of the state of oxidation of the bulk oxide in the electrode over a wide range of degrees of oxidation. The properties of the electrode are shown to be determined by the state of a surface phase, which is completely charged when the bulk oxide material in the electrode has been charged to 10% of its total charge capacity. Experiments on sparingly charged electrodes have proved that charging of the bulk oxide does not commence significantly until the electrode is charged to about 1.5%. Consecutive electrochemical reactions possibly involved in the charging process are discussed.


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