The behaviour of the lead dioxide electrode. Part 3.—Overvoltage during oxygen evolution in H<sub>2</sub>SO<sub>4</sub>

Jones, P.; Lind, R.; Wynne‐Jones, W. F. K.

doi:10.1039/tf9545000972

Cited by 50 publications

(27 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…8 and 9). In accordance with the results of Wynne-Jones et al (13) the length of the first discharge plateau as well as that of the second decay (Fig. 1, IihI) increased with the quantity of current passed, i.e.…”

Section: Resultssupporting

confidence: 79%

The Behavior of Lead Electrodes in Sulphuric Acid Solutions

Ekler¹

1964

Can. J. Chem.

View full text Add to dashboard Cite

Lead electrodes were anodically etched in NHpS03H. Immersion potentials, self-passivation potentials, passivation times, PbO?/Oa potential, and the potential of the first discharge plateau were determined in H?SO( solutions ranging from 0.5 to 30.0 N and were found to be concentration-dependent. Interruption of the anodizing current had no detectable influence on passivation time. Data obtained with the anodizing current turned on fall into three categories; those obtained with (1) short-immersion anodes, (2) anodes which had reached a hydrogen-like potential, and (3) anodes which were self-passivated before the current was switched on. AII inflection in the relation between potential and time during charging was investigated. Its length was dependent upon acid concentration and current density, while its potential was +300 & 30 mv, and seemed to correspond to the self-passivation potential. T h e lengths of the first and second discharge plateaus increased with the nr~tnber of coulombs passed and were dependent upon acid concentration, but were identical for electrodes treated by four different methods. The hydrogen-like poteritial appeared to be due to the presence of PbO. PbSOr. The self-passivation potential seemed to be caused by for~nation of PbO.

show abstract

Section: Resultssupporting

confidence: 79%

The Behavior of Lead Electrodes in Sulphuric Acid Solutions

Ekler¹

1964

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…1, which indicates that the PTFE-bonded anode achieved approximately I00 mV saving in potential at 500 A m -2. Tafel slopes for both anodes were approximately 120 mV decade -1, in agreement with previously reported values for Pb/PbO 2 anodes [4]. However, the lifetime of PTFEbonded electrodes was found to be limited by oxidation of the lead substrate, causing detachment of catalyst layers after say > 60h operation, though careful pre-oxidation of the anode substrate is being found to extend the life.…”

Section: Pb/pb02/ptfe-bonded Electrodessupporting

confidence: 85%

New electrodes for oxygen evolution in acidic solution

et al. 1989

View full text Add to dashboard Cite

Conventional electrowinning of metals such as zinc and copper from 1-1.5 kmolm -3 H2SO 4 electrolytes involves anodic oxygen evolution at Pb alloy/PbO2 anodes operating at 200-800 A m -2. The oxygen overpotential, estimated to be about 0.6V, constitutes a significant proportion of the cell voltage (typically 2.5 V for Cu and 3.3 V for Zn). The objective of this work was to lower the anode overpotential and so decrease the process specific energy requirements, by devising new anode materials based on: (1) PTFE-bonded PbO2 catalysts, supported on Pb-Ag alloys; (2) modification of the pore structure of porous electrodes to maximize the utilization of the available surface without the use of PTFE bonding. Both methods are shown to produce significant benefits in lowering oxygen overpotentials, though the latter technique has been tested only in alkaline electrolytes, as yet. However, with the former approach, substrate oxidation through the porous catalyst layer has been found to cause catalyst shedding after > 60 h at 1 kA m -2, though careful pre-oxidation of the anode substrate appears to extend the anode life.

show abstract

“…of initially polarized nickel oxide electrodes and suggested mechanisms involved in the self-discharge process. Other decay studies on various electrodes have been reported by Wynne-Jones et aZ.3- 5 Ruetschi et aZ. 6 and Antonieu and Wetmore.…”

mentioning

confidence: 73%

Significance of e.m.f. decay measurements. Applications to the nickel oxide electrode

Conway¹,

Bourgault²

1962

Trans. Faraday Soc.

View full text Add to dashboard Cite

The significance of observations of rates of e.m.f.-decay on opencircuit at the nickel oxide electrode is examined in terms of the potential dependefice of the surface capacitance associated with the processes occurring during decay. Results are compared with those reported by Lukovtsev and Temerin and it is concluded that a capacity based on the properties of the surface layer (e.g., adsorbed oxygen radicals or a highly oxidized nickel oxide surface phase) must be used rather than one based on the oxidation-reduction behaviour of the bulk phase oxide. Direct micro-volumetric determinations of volumes of oxygen evolved from the electrode during opencircuit e.m.f.-decay allow quantitative comparisons to be made between true Tafel slopes and open-circuit e.m.f.-decay slopes. These slopes are shown to be identical only when the volume of oxygen evolved from the surface is a linear function of e.m.f. When the e.m.f. is a logarithmic function of the oxygen evolved, Tafel and decay slopes are shown to differ in the theoretically expected direction. The linear and logarithmic behaviour with respect to e.m.f. and volumes of oxygen evolved can be shown to follow as limiting conditions of the adsorption behaviour of oxygen at the electrode surface, depending upon the extent of surface coverage. The kinetic significance of the surface capacitance is discussed in relation to the e.m.f. decay behaviour. 593* This is based on a figure of 50 mA per actual plaque used (7-5 x 2 5 x 0.1 cm in size).* Very recent work by Conway and Gileadi indicates that when the true reversible potentials (as distinct from mixed potentials 2) are deduced, the Nernst redox slope for the bulk material is, in fact insignificantly merent from zero within the experimental error of f 5 mV.

show abstract

The behaviour of the lead dioxide electrode. Part 3.—Overvoltage during oxygen evolution in H₂SO₄

Cited by 50 publications

References 0 publications

The Behavior of Lead Electrodes in Sulphuric Acid Solutions

The Behavior of Lead Electrodes in Sulphuric Acid Solutions

New electrodes for oxygen evolution in acidic solution

Significance of e.m.f. decay measurements. Applications to the nickel oxide electrode

Contact Info

Product

Resources

About

The behaviour of the lead dioxide electrode. Part 3.—Overvoltage during oxygen evolution in H2SO4

Cited by 50 publications

References 0 publications

The Behavior of Lead Electrodes in Sulphuric Acid Solutions

The Behavior of Lead Electrodes in Sulphuric Acid Solutions

New electrodes for oxygen evolution in acidic solution

Significance of e.m.f. decay measurements. Applications to the nickel oxide electrode

Contact Info

Product

Resources

About

The behaviour of the lead dioxide electrode. Part 3.—Overvoltage during oxygen evolution in H₂SO₄