Approximate Solution of Non-Linear Reaction Diffusion Equations in Homogeneous Processes Coupled to Electrode Reactions for CE Mechanism at a Spherical Electrode

A. Eswari, S. Usha, L. Rajendran

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DOI: 10.4236/ajac.2011.22010                

Abstract

A mathematical model of CE reaction schemes under first or pseudo-first order conditions with different diffusion coefficients at a spherical electrode under non-steady-state conditions is described. The model is based on non-stationary diffusion equation containing a non-linear reaction term. This paper presents the complex numerical method (Homotopy perturbation method) to solve the system of non-linear differential equation that describes the homogeneous processes coupled to electrode reaction. In this paper the approximate analytical expressions of the non-steady-state concentrations and current at spherical electrodes for homogeneous reactions mechanisms are derived for all values of the reaction diffusion parameters. These approximate results are compared with the available analytical results and are found to be in good agreement.

Keywords

Non-Linear Reaction/Diffusion Equation, Homotopy Perturbation Method, CE Mechanism, Reduction of Order, Spherical Electrodes

Conflicts of Interest

The authors declare no conflicts of interest.

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