Heterogeneous Kinetics by Scanning Electrochemical Microscopy
This Demonstration shows an application of Scanning Electrochemical Microscopy (SECM) to determine the heterogeneous kinetics of a conductive substrate with positive feedback mode.
On a conductive substrate, a redox reaction operates under kinetic control (i.e., it depends on the value of the forward rate constant and the reverse rate constant ). Hence the flux of feedback to the tip depends on the values of and .
In this Demonstration, you can choose the reverse () or the forward reaction () that occurs on the substrate. Then, you can manually fit the experimental data (red points) by the theoretical line (blue line) to find the reaction rate . This reaction rate can also be fitted by the Mathematica built-in function FindFit when you check the "fit" checkbox.
To find the standard rate constant , you provide the potential applied to the substrate and the standard potential of the reaction on the substrate; is found by the Butler–Volmer equation.
 C. G. Zoski, "Scanning Electrochemical Microscopy," Handbook of Electrochemistry, Amsterdam: Elsevier, 2007 pp. 471–540.