靛蓝胭脂红波薄层光谱电化学研究(I)

采用SnO_2石英玻璃组装的光透薄层电解池, 结合紫外可见光谱现场监测技术, 研究了靛蓝胭脂红水溶液的电化学还原与氧化过程. 测定了不同pH下的式电极电位(E~0)和电子转移数(n). 实验结果表明, 靛蓝胭脂红在SnO_2电极上的还原为准可逆的两电子转移过程, 而它的氧化则为不可逆电极过程. 由电解现场检测的光谱, 初步探讨了电解还原与氧化的反应机理。

Thin-Layer Spectroelectrochemical Investigation on Indigo Carmine

The mechanisms of electrochemical reduction and electrochemical oxidation of Indigo Carmine were investigated by means of thin-layer spectroelectrochemical tech-nique at a SnO_2-quartz optically transparent electrode cell. The formal potentials and electron transfer numbers of the reduction of Indigo Carmine were determined at different pHs. The results showed that the reduction of Indigo Carmine at SnO_2 electrode is a quasireversible two-electron transfer process and its oxidation is a irreversible electron transfer process. The mechanisms of the electroreduction and electro-oxidation were discussed on the basis of the spectrum recorded in situ during the electrochemical process.