Square-Wave Voltammetry Applied to Thin-Layer Cell

7 Square-Wave Voltammetry Applied to Thin-Layer Cell 

Square-wave voltammetiy apphed to experiments with a thin-layer electrochemical cell is a valuable analytical tool for determination of small amounts of analytes [46,154-157], e.g., the determination of drugs and species with biological activity [158]. Over the past decades, SWV has been frequently applied to study physiologically active compounds embedded in a thin-film that is imposed on an electrode snrface [78,159]. Moreover, a graphite electrode modified with a thin-film 

The current chapter gives an accoimt on the theory of SWV for systems oc-enrring in a finite diffusion space. The experimental verification of the theoretical 

In the modeling of the electrode reaction (2.230) proceeding in a thin-layer cell or within a thin film on the electrode surface, the differential equation (1.2) and (1.3), together with the following boundary conditions (2.231) to (2.233) have to be considered  

The physical meaning of condition (2.233) is that the diffusion of the electroactive species is blocked at the distance x = Z, i.e., where L is the thickness of the film. This bormdary condition complicates significantly the mathematical procedure compared to the semi-infinite diffusion case. To resolve the mathematical complexity, recently a novel mathematical approach has been developed which is based on the modification of the step function method [162], as elaborated in more detail in the Appendix. The numerical solution for a reversible electrode reaction is given by [155]  

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