Application of the Convective Diffusion Equation with Potential-Dependent Boundary Conditions to the Charge Transfer Problem in Four-Electrode Electrochemical Cell on the Condition of Small Hydrodynamic Velocity

作者：Agafonov Vadim M^*; Egorov Egor V; Bugaev Alexander S

来源：International Journal of Electrochemical Science, 2016, 11(1): 359-373.

• Ion transport
• convective diffusion
• sensors
• electrode kinetics
• hydrodynamics

To describe charge transfer in a four-electrode electrochemical cell for the Iodide-Iodine redox system, the Nernst-Plank equations and the boundary conditions based on the kinetics of the reactions on the electrodes have been modified, assuming the small active component (I-3(-)) concentration relative to the background electrolyte concentration (components I- and metal ions Me+). The resulting mathematical model comprises the convective diffusion equation and the Laplace type equation for the potential, while the boundary conditions on the electrodes bond the potential and the concentration of I-3(-). The approach was applied for the classical one-dimensional model in case of small hydrodynamic velocity. For realistic parameters of the system, the modelling results are different from the solution of the convective diffusion equation with the fixed concentration on the electrodes and are in good agreement with the experimental data.

• 出版日期2016-1