碳纤维微电极研究——ⅩⅩ.甲苯胺蓝在碳纤维微盘电极上的电化学性质

Investigation on Carbon Fiber Microelectrodes X X . The Electrochemical Behaviours of Toluidine Blue at a Carbon Fiber Microdisk Electrode

研究了甲苯胺蓝在碳纤维微盘电极上的电化学行为,探讨了pH对甲苯胺蓝电极反应过程的影响,确定在pH<3.7,3.7<pH<5.5及pH>5.5时,参与电极过程的H^+数分别为3,2和1;测定了甲苯胺蓝的扩散系数及在碳纤维微盘电极上的电荷转移系数α,标准电子转移速率常数k^(?)和式量电位E^(?),提出了不同pH下电极反应的机制,对甲苯胺蓝在碳纤维微盘电极上的吸附性能进行了探索,并测定了吸附控制条件下的动力学参数.

The electrochemical behaviour of toluidine blue (TB) at a carbon fiber microdisk electrode was studied. The effect of pH on the electrode process was investigated, and the number of H+ in the electrode process is 3 at the range of 1.5- 3.7, 2 at pH3.7- 5.5 or 1 and pH5.5-10.7, respectively. The apparent standard heterogeneous electron transfer rate constant k°' , and E°' of TB at various pH on the carbon fiber microdisk electrode were determined. The overall electrode reaction mechanism of toluidine blue was proposed. The adsorbability of TB on the electrode was studied, and the kinetics parameters in the control of adsorption process were determined.