Chang Byoung-Yong, Park Su-Moon
Department of Chemistry and Center for Integrated Molecular Systems, Pohang University of Science and Technology, Pohang, Gyeongbuk 790-784, Korea.
Anal Chem. 2007 Jul 1;79(13):4892-9. doi: 10.1021/ac070169w. Epub 2007 May 27.
We report a novel comprehensive Fourier transform electrochemical impedance spectroscopic (FTEIS) analysis method of a series of chronoamperometric currents obtained during staircase cyclic voltammetric (SCV) experiments. In our method, FTEIS analysis of a set of chronoamperometric currents recorded upon applying a series of small potential steps during an SCV experiment provides a complete description of an electron-transfer reaction at the electrode/electrolyte interface in forms of equivalent circuit elements. Conversion of the circuit elements thus obtained from the analysis allows electrode kinetic parameters including the electron-transfer rate constant, transfer coefficient, diffusion coefficient, and double layer capacitance as well as thermodynamic parameters such as the half-wave potential and the apparent number of electrons transferred to be determined. Theories for obtaining an ac admittance voltammogram, as well as both the thermodynamic and mass-transfer kinetic parameters thereof, from the SCV data have been developed and verified. A decided advantage of the method is that it provides completely self-contained information regarding an electron-transfer reaction from a single pass of the SCV experiment.
我们报告了一种新颖的综合傅里叶变换电化学阻抗谱（FTEIS）分析方法，用于分析在阶梯循环伏安法（SCV）实验中获得的一系列计时电流。在我们的方法中，对在SCV实验期间施加一系列小电位阶跃时记录的一组计时电流进行FTEIS分析，以等效电路元件的形式完整描述电极/电解质界面处的电子转移反应。通过分析得到的电路元件的转换，能够确定包括电子转移速率常数、传递系数、扩散系数和双层电容在内的电极动力学参数，以及诸如半波电位和表观转移电子数等热力学参数。已经开发并验证了从SCV数据获得交流导纳伏安图及其热力学和传质动力学参数的理论。该方法的一个显著优点是，它通过单次SCV实验就能提供关于电子转移反应的完全自包含信息。
