Electrochemical Capacitive Charging in Porous Materials. Discriminating between Ohmic Potential Drop and Counterion Diffusion

2019 ◽  
Vol 2 (7) ◽  
pp. 4981-4986 ◽  
Author(s):  
Cyrille Costentin ◽  
Jean-Michel Savéant
Keyword(s):  
Porous Materials ◽  
Potential Drop ◽  
Ohmic Potential Drop ◽  
Capacitive Charging

Corrosion of Electronic and Magnetic Devices and Materials

1996 ◽  
Vol 451 ◽  
Author(s):  
Gerald S. Frankel
Keyword(s):  
Thin Film ◽  
Failure Modes ◽  
Galvanic Corrosion ◽  
Potential Drop ◽  
Magnetic Devices ◽  
Disk Structure ◽  
Magnetic Layers ◽  
Ohmic Potential Drop ◽  
Corrosion Problem ◽  
Corrosion Susceptibility

ABSTRACTCorrosion of thin film structures commonly used in electronic and magnetic devices is discussed. Typical failure modes are presented, and galvanic corrosion is discussed in some detail since it is one common problem with such devices. A graphical explanation for the determination of the ohmic potential drop during galvanic corrosion is presented. The corrosion problem of thin film disks is shown to have changed during the past ten years owing to changes in disk structure. The corrosion susceptibility of two antiferromagnetic alloys used for exchange coupling to soft magnetic layers is discussed.

scholarly journals Kinetics of electrochemical intercalation of lithium ion into Li[Li0.2Co0.3Mn0.5]O2 electrode from Li2SO4 solution

2021 ◽  
Vol 23 (09) ◽  
pp. 656-687
Author(s):  
K.C. Mahesh ◽  
◽  
G.S. Suresh ◽  
Keyword(s):  
Aqueous Electrolyte ◽  
Lithium Ion ◽  
Potential Drop ◽  
Charge Transfer Resistance ◽  
Transfer Resistance ◽  
Ohmic Potential Drop ◽  
Ion Intercalation ◽  
Time Invariant ◽  
Kinetics Of ◽  
Titration Technique

The kinetics of electrochemical lithium ion intercalation into Li[Li0.2Co0.3Mn0.5]O2 electrode in 2 M Li2SO4 aqueous electrolyte has been studied using two electroanalytical methods, namely, potentiostatic intermittent titration technique (PITT) and galvanostatic intermittent titration technique (GITT). The results are compared with those from nonaqueous electrolytes. Layered, lithium-rich Li[Li0.2Co0.3Mn0.5]O2 cathode material was synthesized by reactions under autogenic pressure at elevated temperature (RAPET) method. The effects of ohmic potential drop and charge-transfer resistance have been considered while predicting the current transients obtained with aqueous electrolyte. For PITT and GITT, we have defined their characteristic time-invariant functions, It1/2 and dE/dt1/2, respectively to present the diffusion time constant τ. Application of different theoretical diffusion models for treating the results obtained by the above-mentioned techniques allowed us to calculate the diffusion coefficient of lithium ions (D) at different potentials (E). The intercalation process is explained by considering the possible attractive interactions of the intercalated species in terms of Frumkin intercalation isotherm. We have observed a strictcorrespondence between the peaks of the intercalation capacitance and the minima in the corresponding log D vs. E curve.

Ohmic potential drop during alkaline water electrolysis

1982 ◽  
Vol 27 (9) ◽  
pp. 1207-1218 ◽  
Author(s):  
L.J.J. Janssen ◽  
J.J.M. Geraets ◽  
E. Barendrecht ◽  
S.D.J.van Stralen
Keyword(s):  
Water Electrolysis ◽  
Potential Drop ◽  
Alkaline Water Electrolysis ◽  
Alkaline Water ◽  
Ohmic Potential Drop

THE ELECTROCHEMICAL MECHANISM OF SULFIDE SELF‐POTENTIALS

Geophysics ◽  
1960 ◽  
Vol 25 (1) ◽  
pp. 226-249 ◽  
Author(s):  
Motoaki Sato ◽  
Harold M. Mooney
Keyword(s):  
Water Table ◽  
Potential Drop ◽  
Reducing Agents ◽  
Oxidation Potential ◽  
Simultaneous Reduction ◽  
Oxidizing Agents ◽  
Ore Body ◽  
Oxidation Reduction ◽  
Ohmic Potential Drop ◽  
Different Depths

Self‐potentials associated with a sulfide ore body result from the ohmic potential drop within the country rocks. The electric current is produced by separate but simultaneous reduction of oxidizing agents near the surface and oxidation of reducing agents at depth. The ore does not participate directly in either reaction, but serves as a conductor to transfer the electrons from the reducing agents to the oxidizing agents. The possibility for the above reactions to occur depends upon differences in oxidation potential of ground waters at different depths. In the zone of weathering, the oxidation potential is controlled by the reduction mechanism of oxygen, and ranges in value from 0.2 to 0.7 volt (on the hydrogen scale). If the ore tends to oxidize at some lower potential, then the latter is the available one. In the zone beneath the water table, the potential is probably controlled by the oxidation‐reduction equilibria of iron‐rich minerals, and ranges in value from 0 to −0.3 volt. The available potential is independent of ore type. The maximum potential difference available to produce natural currents is estimated at: graphite 0.8, pyrite 0.7, covellite 0.6, chalcocite 0.5, galena 0.3 volt. Self‐potentials will be large if the ore body (1) is composed of minerals difficult to oxidize, (2) has low electrical resistance (physical continuity together with low resistivity), (3) extends vertically across the water table, and (4) exists close to the surface.

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