An assessment of comparative methods for approaching electrode polarization in dielectric permittivity measurements

Abstract

We examine the validity of three common methods for analysis and correction of the electrode polarization (EP) effect in dielectric spectroscopy measurements of conductive liquid samples. The methods considered are (i) algorithmic treatment by modeling the EP behavior at constant phase angle, (ii) varying the size of the electrode gap, and (iii) polypyrrole (PPyPss) layered electrodes. The latter is a relatively recent innovation suggested to be an efficient solution. We demonstrate that PPyPss coated electrodes do not diminish the effect of EP, and even add relaxation processes of its own. Our conclusion is that these polymer coated electrodes are not suitable for the correction of electrode polarization.

Understanding Dielectrics: Impact of External Salt Water Bath

“…Clearly the S-DOC configurations had higher effective dielectric values than the DI-DOC configuration, but it was also clear that the DI-DOC was displaying effective dielectric values at least five orders of magnitude higher than the classically reported dielectric value for water, ~80 [26]. These high values of the dielectric constant for DI at a low frequency/long discharge period were similar to those reported elsewhere [14,15] for distilled water.…”

“…It is notable that other groups studying the dielectric value of water at low frequency (ca. near 1 Hz) report values of dielectric constant very similar to those reported here [14,15]. Moreover; those teams used other methods, not the constant current method employed herein.…”

“…In addition to these experiments, studies of the behavior of (1) DI, and (2) DI containing ~5.0 wt % NaCl the dielectric between the electrodes is presented. The finding that the dielectric constant of DI water is remarkably high, in fact >10 9 in particular circumstances, confirms earlier studies showing pure water, at low frequency, has a remarkably high dielectric value [14,15]. These results suggest, according to SDM theory, that well organized dipole formation must occur in water exposed to electric fields, and suggest there is value in continuing research on the dielectric behavior of water.…”

Room Temperature Dielectric Pulse Effect in Organic Mixtures

“…This clearly shows that the dielectric pulse behavior is caused by the thin insulation layer formed during the solid–liquid phase transition, and the dielectric constant depends on the thickness of the insulation layer. This phenomenon is also reported as the “blocked electrode” effect . When the electrode is coated by the insulating material, a new interfacial relaxation between the sample and the insulating material will arise.…”

Rough Gold Electrodes for Decreasing Impedance at the Electrolyte/Electrode Interface

“…However, the fragility of electrodeposited PB under mechanical contact, poor reproducibility of deposition, its hydrophobic behavior and bio-toxicity [27] have limited its use in physiological measurements. Different electrode materials and fabrication techniques, including IrOX [9, 28, 29], TiN [9], Pedot-Nanotubes [22], conductive polymers [9, 22, 30–32] and activated carbon [33], were sought to reduce EP. However, the common disadvantage of these materials is their electrical stability under mechanical contact.…”