Regression analysis of electrochemical data with expanding space grid digital simulation at spherical electrodes.
Regression analysis of electrochemical data with expanding space grid digital simulation at spherical electrodes.
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球形电极扩展空间网格数字模拟电化学数据的回归分析。
DOI：
10.1021/ac00298a047
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发表时间：
1986
影响因子：
7.4
通讯作者：
Rusling,JF
中科院分区：
文献类型：
--
作者：
Arena,JV;Rusling,JF
描述了一种与扩展空间网格数字模拟相结合的计算机非线性回归方法，用于分析在球形电极处获得的单个电化学响应曲线。这种非线性回归/数字模拟程序快速而准确，并且可以轻松适应复杂的电化学机制。该方法使用具有 0.5% 正态分布噪声的理论数据，为可逆和准可逆单电子转移提供了良好的线性扫描伏安法和单电位步长计时库仑法精度。对于9, 10-二苯基蒽在干燥二甲基甲酰胺中的可逆单电子还原，通过回归模拟方法获得的D和E值与通过常规方法评估的值非常一致。对于准可逆电荷转移反应可以获得异质速率常数。对于菲啶对 4-氯联苯的双电子二阶电催化还原，该方法得到的速率常数为 (1.4±0.1) X 103 M~ 1 s~\，与之前在伪一阶条件下估计的值 (1.6±0.6) X 103 M~ 1 s" 1 吻合，精度更高。非线性回归能力分析电化学响应曲线以阐明电极反应机制和确定动力学和热力学参数已得到充分证明，最近的一些例子包括通过电位步骤实验准确和精确地确定复杂电极反应中的扩散系数、表面浓度 (1) 和化学步骤的速率常数 (2-4)，根据恒电位电流电位数据估计标准电位和异质速率常数 (5)，计算氧化还原的化学速率常数。循环伏安图的电催化 (6)、光电催化 (7) 和电二聚 (8) 反应，以及从方波伏安图确定异质速率参数 (9) 的非线性回归与偏差模式识别已被用于自动化方法中，以从电化学响应曲线中识别电极反应机制 (5, 10)。最近描述的基于电流、电势和电流半积分之间关系的全局分析方法是分析单个电化学实验的一种有趣的替代方法，但是，它需要大量的数据转换和图形测试，并且迄今为止仅针对异质电子转移和线性扩散而开发，使用非线性回归分析需要以下形式的数学模型。
A computerized nonlinear regression method coupled to ex-panding space grid digital simulation for analyzing Individual electrochemical response curves obtained at spherical electrodes Is described. This nonlinear regression/dlgltal simula-tion procedure Is rapid and accurate and can be readily adapted to complex electrochemical mechanisms. The me-thod gave good accuracy for linear-sweep voltammetry and single potential-step chronocoulometry using theoretical data with 0.5% normally distributed noise for reversible and qua-si-reverslble one-electron transfers. For the reversible one-electron reduction of 9, 10-dlphenylanthracene In dry di-methylformamlde, values of D and Eobtained by the re-gression-simulation method were In excellent agreement with those evaluated by conventional means. Heterogeneous rate constants can be obtained for quasl-reverslble charge transfer reactions. For the two-electron, second-order electrocatalytlc reduction of 4-chloroblphenyl by phenanthridlne, the method gave a rate constant of (1.4±0.1) X 103 M~ 1 s~\In excellent agreement with and of better precision than a previously es-timated value of (1.6±0.6) X 103 M~ 1 s" 1 obtained under pseudo-first-order conditions.Capabilities of nonlinear regression in analyzing electro-chemical response curves for elucidation of electrode reaction mechanisms and for determining kinetic and thermodynamic parameters have been amply demonstrated. Some recent examples include accurate and precise determinations of diffusion coefficients, surface concentrations (1), and rate constants of chemical steps (2-4) in complex electrode reac-tions from potential-step experiments, estimating standard potentials and heterogeneous rate constants from potentios-tatic current-potential data (5), computation of chemical rate constants for redox electrocatalytlc (6), photoelectrocatalytic (7), and electrodimerization (8) reactions from cyclic voltam-mograms, anddetermining heterogeneous rate parameters from square-wave voltammograms (9). Nonlinear regression coupled with deviation-pattern recognition has been used in automated methods to identify electrode reaction mechanisms from electrochemical response curves(5, 10). A major ad-vantage of this technique is that it allows for mechanistic analysis and accurate estimation of parameters fromall the data in a single response curve. The recently described global analysis method (11), based on relations between current, potential, and the semi-integral of the current, is an interesting alternative for analyzing single electrochemical experiments. However, it requires extensive data transformations and graphical testing, and thus far has been developed only for heterogeneous electron transfer and linear diffusion. The use of nonlinear regression analysis requires a mathematical model of the form