Abstract The analytical and numerical solution of nonlinear diffusion equations are performed to study the chronoamperometric limiting current generated from the electrochemical reaction in a rotating disk electrode for second-order ECE reactions when the chemical step is irreversible. Simple and closed-form of expressions for the concentration of reactant and the current response are obtained as a function of the rotation rate and diffusion coefficients. The effect of various physical parameters on concentration and current have been computed and shown graphically. Also, the concentration/current expressions here derived using hyperbolic function and pade´ approximation technique are in satisfactory agreement with numerical results and limiting case results.

中文翻译：

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求解二阶 ECE 反应旋转圆盘电极非线性方程的新解析方法

摘要 通过非线性扩散方程的解析和数值求解，研究了当化学步骤不可逆时，旋转圆盘电极中电化学反应产生的计时电流极限电流，用于二阶ECE反应。作为旋转速率和扩散系数的函数，获得了反应物浓度和电流响应的简单和封闭形式的表达式。各种物理参数对浓度和电流的影响已被计算并以图形方式显示。此外，这里使用双曲线函数和 pade´ 近似技术导出的浓度/电流表达式与数值结果和极限情况结果令人满意地一致。