Abstract
In this paper, a two-consecutive steps anodic dissolution mechanism is simulated at the atomic level by a Monte Carlo algorithm on a 3D lattice. In contrast with a previous work restricted to the 2D flat case, it is shown that the steady state and transient behaviors are controlled not only by the adsorbed intermediate coverage degree but also by the area of the rough interface build up by the dissolution of interfacial atoms. It is established that the complex impedance behavior results from a combination of the individual frequency responses of these two quantities. The emphasis is put on the specific properties of the impedance induced by the surface roughness relaxation for which a kinetic description is proposed and compared to the Monte Carlo data. It is clearly concluded that, by taking into consideration the surface re-arrangement, the number of frequency domains in the impedance may be larger than predicted by the derivation of a kinetic model on a flat interface.
Original language | British English |
---|---|
Pages (from-to) | 6779-6787 |
Number of pages | 9 |
Journal | Electrochimica Acta |
Volume | 54 |
Issue number | 27 |
DOIs | |
State | Published - 30 Nov 2009 |
Keywords
- Computer simulation
- Electrochemical impedance
- Inductive loop
- Model
- Surface relaxation