Hydrodynamics with heated microelectrodes
Voltammetry with continuously heated microelectrodes yields well-defined sigmoidal current-voltage curves. Unlike hydrodynamic electrodes, the surface temperature of a heated electrode can be adjusted arbitrarily within a certain range. Inside a thermal layer, a virtually stagnant diffusion layer of constant thickness δ diff exists. δ diff is independent of temperature within a certain range. On the basis of this theory, equations are derived which play a similar role to, for instance, the Levich equation for the rotating disk electrode. Reasonable agreement of the derived relationship with the results from voltammetric experiments is obtained.
KeywordsHeated electrodes Voltammetry Reversible redox couples Theory Diffusion-limited current