Superficial exchange current density

The volmnetric exchange current density (A cm ) should not be confused with the superficial exchange current density (A cm ). The first value is a local characteristic of a CCL, proportional to the local concentration of catalyst particles (to be precise, to their active surface) . In contrast, parameter is an integral characteristic of the CL. This parameter includes CL thickness imder variable h(x) the generalization of (1.38) is obvious... 

Superficial exchange current density (A m ) characteristic current density (A m )... 

Carbon corrosion superficial exchange current density (A cm" ) Carbon corrosion current density on the anode (A cm ). Equation 5.223... 

In electrocatalysis, the activity of different electrocatalysts is usually expressed via the exchange current I0, and the specific activity, via the exchange current density, iQ (A cm-2), still often computed on the basis of the superficial electrode surface area. Only when the current is normalized using the true surface area of the electrode-electrolyte interface, the comparison between different electrocatalysts is truly meaningful. The determination of the true surface area of porous electrodes is discussed in Sect. 2.3.5. 

Constant given in Table 1 reduced height of an electrode (cm) current density (A/cm ) superficial current density (A/cm ) exchange current density (A/cm ) electric current (A) polarization parameter nucleation rate (s ) mass transfer coefficient (cm/s)... 

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