Tafel Slope and Distribution of Potential

The slope of the plot of logarithm of current density versus potential, which characteristically is linear for an activation-controlled reaction, is defined as the Tafel slope. The Tafel slope determined in the exponential region of an i-V curve in HE solutions is about 60 mV/decade for p types and heavily doped n types of silicon samples as shown in Table 5.3. For lowly doped n-Si, since illumination is required 

TABLE 5.3. Tafel Slope of i-V Curves in the Exponential Region 

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