金电极上偶氮腺嘌呤的电化学行为研究

Electrochemical Behaviors of Azopurine on Gold Electrodes

本文研究了光滑金电极上偶氮腺嘌呤的电化学特性,并确定了相关动力学参数.在含偶氮腺嘌呤的0.2mol·L-1的磷酸盐缓冲液(PBS,pH=4.0~10.0)中,发现其循环伏安图上出现一对氧化还原峰.基于对扫速和伏安峰值电位的分析,结果表明这是一个由吸附控制的可逆偶氮腺嘌呤氧化还原电化学过程.当pH值从低到高改变时,氧化还原峰值向负电位移动,证实H+参与了该反应.通过进一步实验数据分析和电极表面吸附量计算,发现该反应为分步进行的两电子两质子反应.最后,通过快速循环伏安扫描方法确定了电化学过程的表观传递系数α和表观速率常数ks.

In this paper,we studied the electrochemical behaviors of azopurine on polished gold electrodes with cyclic voltammetry(CV).On the basis of analyzing scan rate and peak current,it was supposed that the redox process belonged to a reversible process controlled by adsorption in 0.2 mol·L-1 PBS(pH=4.0~10.0)solutions.The potentials of redox peaks moved more negatively with increasing pH value.This proved that the H+proton has participcted in the electrochemical reaction.The further data analysis and the calculation of surface adsorption excess demonstrated that the reaction was a two-proton and two-electron process.Finally,the apparent transfer coefficientαand the apparent rate constant kswere determined by the fast-scan cyclic voltammetry method.