Abstract
The steady-state current for a 'ring-like' microelectrode is considered, when the electrode reaction rate is not sufficiently large that the diffusion of the electroactive species is the rate-limiting transport process. This régime is particularly relevant for micro-ring electrodes (which the present formulation includes), because the criterion for diffusion-limited transport is much more stringent for a thin micro-ring electrode than for a micro-disc of comparable size. First an approximate solution is presented for the steady-state current for a ring-like microelectrode, valid for any value of the electrode reaction rate provided the ring is thin. For the special case of a thin, plane-mounted micro-ring electrode, numerical results are given and the surface current density distribution is shown. In this case the total current is found to be in close agreement with a semi-empirical approximation due to A. Szabo (J. Phys. Chem., 91 (1987) 3108). A micro-ring electrode with an arbitrary ratio of inner to outer radius is then considered, and the steady-state current is calculated numerically as a function of the electrode reaction rate for a range of geometries, extending from a complete disc to a thin ring.
Original language | English (US) |
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Pages (from-to) | 277-283 |
Number of pages | 7 |
Journal | Journal of Electroanalytical Chemistry |
Volume | 396 |
Issue number | 1-2 |
DOIs | |
State | Published - Oct 31 1995 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Analytical Chemistry
- Chemical Engineering(all)
- Electrochemistry
Keywords
- Ring-like microelectrode
- Steady-state current