Some Key Aspects of Electrochemical Promotion

The NEMCA time constant t is defined as the time required for the rate increase Ar to reach 63% of its steady-state value during a gal-vanostatic transient, such as the one shown in Fig. 17. Such rate transients can usually be approximated reasonably well by 

A general observation in NEMCA studies with conductors is that the magnitude of r can be predicted from 

In the experiment of Fig. 17, the A value at steady state is 74,000. A reaction is said to exhibit the NEMCA effect when A .  

An important step in the elucidation of the origin of NEMCA was the observation that the magnitude of A can be estimated for any reaction 

As previously discussed, Eq. (53) has been also derived theoretically and is in good qualitative agreement with experiment over five orders of magnitude (Fig. 18). This important relationship shows that  

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