Electrocatalytic reduction of oxygen on the surface of glassy carbon electrodes modified with plumbagin
Electrocatalytic reduction of oxygen on the surface of glassy carbon electrodes modified with plumbagin
复制标题
白铅修饰玻碳电极表面电催化还原氧
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
M. Hamzehloo
中科院分区：
文献类型：
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作者：
M. Ardakani;P. E. Karami;H. Zare;M. Hamzehloo
摘要：采用循环伏安法、计时电流法和旋转圆盘电极技术研究了白花丹素修饰玻碳电极的制备和电化学特性。氧的电还原的循环伏安图显示在空气饱和的磷酸盐缓冲液pH = 7和扫描速率10 mV s-1中在约-0.289 V处的增强电流峰。用循环伏安法测定了氧在玻碳上还原的热力学和动力学参数。优化了实验条件，并对催化反应机理进行了探讨。测得的E°′（V vs. Ag/AgCl）、表观电子转移速率常数ks（s−1）、修饰电极表面O2还原的非均相速率常数kh（M−1 s−1）和α（氧的电荷转移系数）分别为-0.146，23.4，9.9 × 103和0.57。此外，白花丹素对H2 O2的还原反应具有很强的催化活性。
Abstract.The preparation and electrochemical characterization of glassy carbon electrodes modified with plumbagin were investigated by employing cyclic voltammetry, chronoamperometry and rotating disc electrode techniques. The cyclic voltammograms of the electroreduction of oxygen showed an enhanced current peak at approximately −0.289 V in air-saturated phosphate buffer pH = 7 and scan rate 10 mV s−1. The thermodynamic and kinetic parameters of the reduction of oxygen at glassy carbon have been evaluated using cyclic voltammetry. The experimental parameters were optimized and the mechanism of the catalytic process was discussed. The obtained values of E°′ (V vs. Ag/AgCl), the apparent electron transfer rate constant ks (s−1), heterogeneous rate constant for the reduction of O2 at the surface of the modified electrode kh (M−1 s−1) and α (charge transfer coefficient of oxygen) were as follows: −0.146, 23.4, 9.9 × 103 and 0.57, respectively. In addition, plumbagin exhibited strong catalytic activity toward the reduction of H2O2.