(Invited) Dynamic and Coverage Effects in EIS

Abstract

The effect of sweep rate on the validity of impedance measurements made dynamically when sweeping the potential is investigated by numerical solution of the differential equations for a simple adsorption reaction. The same method is used to show that dynamic EIS can detect a nucleation-growth-collision mechanism through a negative time constant, and that measurement in the unstable regime is possible, even though the data is not Kramers-Kronig transformable. The utility of the concept of the rate-determining step in EIS is demonstrated for a simple example.