Electrode polarization curves

Figure 4. Electrode polarization curve for Fe2+-Fe3+ system at (Fe2+ = Fe3+) concentration of 10 M, pH of 2. Other conditions same as for Figure 3...

Figure 6. Electrode polarization curves for oxygen-containing solutions in otherwise-pure water. Curves are schematic but in accord with available data at significant points...

The electrode polarization curve characteristics exhibited above are typical of those seen in many fuel cell electrodes. Thus a potential application of the ADM approximate solutions is determining the key electrochemical and mass transport parameters. 

Figure 10 Schematic presentation of signal from a sample with conductivity [signal V (t)] and the correction exponential function described by the electrode polarization curve Vec(t). (From Ref. 72. With permission from Elsevier Science B.V.)...

Three different regimes of current density could be identified in electrode polarization curves, as indicated in Figure 2.9 (1) a kinetic regime at small... 

The gold electrode polarization curves registered in all the atmospheres are similar (Fig. 5) at high current densities (/ > 10 mA/cm, E —(0.9- 0.6) V). The slopes of the Tafel sections are equal to 160 mV in the CO2 or CO atmosphere and 240 mV in the He atmosphere. If the current is less than 10 mA/cm (Fig. 5), the influence of the gaseous atmosphere is clearly pronounced. In the CO atmosphere the polarization curves have a maximum-current platform extended along the potential axis (up to 0.8- 1.0 V). A small current jog 0.1 0.15 V long was observed. A smoothly descending polarization curve is obtained in the CO2 atmosphere. The stationary potentials (Fig. 7) are similar in CO2 or He atmosphere but differ sharply in CO. In the CO atmosphere the stationary potentials at... 

Based on this discussion, three current density regimes can be distinguished in electrode polarization curves ... 

FIGURE 4.27 (a) The points the DMFC polarization curves for the indicated working temperatures (data from Argyropoulos et al. (2(X)2)). The dotted lines the linear fit according to Equation 4.215. The slopes of the straight line (the CCL resistivities) are collected in Table 4.3. (b) The calculated electrode polarization curve versus the sum of the useful and crossover current densities jo + jcrossfl for tbe indicated parameter jS. ... 

It was found that in the N2 saturated, solution reduction peak due to oxygen was not observed for both modified electrodes. Polarization curves (not shown see [48]) showed that in the absence of methanol, for the FeBiPc/MWCNT catalyst, an onset potential of 0.85 V versus standard hydrogen electrode (SHE) was observed, which was higher than that found for BiFePc alone [48]. This response was attributed to an outstanding electronic conductivity of MWCNT relative to the FeBiPc. 

Yeum, K. Devereux, O. (1989). An iterative method for fitting complex electrode polarization curves. Corrosion 45(6) 478-487. 

Figure 2. Typical change-discharge cyde (a) and single-electrode polarization curves (b) of the U,TiS2 /ua04-EC-PC-PAN/U(i- )Co02 thin film cell at room temperature and at a 0.02 mA-cm current density. Derived from reference 9. Reproduced by permission of the Bectrochemical Society, Inc.

---