Ideal depolarized electrode

An -> ideal nonpolarizable electrode is one whose potential does not change as current flows in the cell. Much more useful in electrochemistry are the electrodes that change their potential in a wide potential window (in the absence of a - depolarizer) without the passage of significant current. They are called -> ideally polarized electrodes. Current-potential curves, particularly those obtained under steady-state conditions (see -> Tafel plot) are often called polarization curves. In the -> corrosion measurements the ratio of AE/AI in the polarization curve is called the polarization resistance. If during the -> electrode processes the overpotential is related to the -> diffusional transport of the depolarizer we talk about the concentration polarization. If the electrode process requires an -> activation energy, the appropriate overpotential and activation polarization appear. 

Current-potential curves, particularly those obtained under steady-state conditions, are sometimes called polarization curves. We have seen that an ideal polarized electrode (Section 1.2.1) shows a very large change in potential upon the passage of an infinitesimal current thus ideal polarizability is characterized by a horizontal region of an i-E curve (Figure 1.3.5a). A substance that tends to cause the potential of an electrode to be nearer to its equilibrium value by virtue of being oxidized or reduced is called a depolarizer An... 

Faradme Processes. Consider an ideally polarized electrode only nonfaradaic processes occur, no charges cross the interface, and no continuous current can flow. Upon addition of a substance that can be oxidized or reduced at the particular potential difference, current now flows—the electrode is depolarizedy and the substance responsible is called a depolarizer. 

An overpotential contribution is required for both the anodic and the cathodic reaction and, in this case, it is mainly to oxidize water at the Pt anode. As copper is deposited and the concentration of Cu ions falls, both the ohmic potential drop IR across the electrolyte and the overpotential decrease. If we assume that the solution resistance R remains fairly constant, the ohmic potential drop is directly proportional to the net cell current. The overpotential increases exponentially with the rate of the electrode reaction. Once the Cu ions cannot reach the electrode fast enough, we say that concentration polarization has set in. An ideally polarized electrode is one at which no faradaic reactions ensue that is, there is no flow of electrons in either direction across the electrode-solution interface. When the potential of the cathode falls sufficiently to reduce the next available species in the solution (H" ions, or nitrate depolarizer), the copper deposition reaction is no longer 100% efficient. 

Ideal Non-polarizable (Depolarized) Electrode it is a type of electrode that does not change its potential upon passage of current example reference electrode. 

It was shown that almost ideal depolarization was achieved at the PEDOT DCE interface at a potential scan rate slower than 50 mV/s. Additionally, if total charge used was below 20 pC/cm, potential shift was smaller than 15 mV. Thus, such electrode can be used as a reference/counter electrode in organic phase. 

Tensor dsjk characterizes the surface piezoeffect existing for any lattice symmetry, including cubic one. The depolarization field Ej for the considered monodomain film with ideal electrodes can be written in the form [12]... 

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