对苯二酚在玻碳电极上的电化学行为及其动力学研究

Electrochemical Behaviors of Hydroquinone and its Electrochemical Kinetics on Glassy Carbon Electrode

研究了对苯二酚（HQ）在玻碳电极上于磷酸盐缓冲液（PBS）中的电化学行为及其电化学动力学性质。结果表明：HQ在该电极上有一对可逆的氧化还原峰,峰电流与扫描速度的平方根（v1/2）呈良好的线性关系。这说明HQ在该电极上的伏安行为是一受扩散控制的可逆电化学过程。在pH为6.08的PBS缓冲液中氧化峰电流与HQ的浓度在5.0×10^-6-2.5×10^-5 mol/L范围内呈良好的线性关系,Ipa（μA）=-1.444-0.077 8 c（μmol/L）,相关系数r=0.996 5,检测限为4.75×10^-6 mol/L。同时利用电化学方法确定了该电极反应过程是双电子转移,并测得传递系数α为0.626,扩散系数D为7.4×10-7 cm^2/s,电极反应速率常数kf为6.8×10^-4 cm/s。

The electrochemical behavior of Hydroquinone and its electrochemical kinetics was studied on glassy carbon electrode by Cyclic Voltammetry（CV）,Chronocoulometry（CC） and Chronoamperometry（CA）.The experimental results showed that the catalytic oxidation current of Hydroquinone was linear with its concentration in the range of 5.0 × 10^-6 - 2.5 × 10^-5 mol/L.The correlative coefficient was 0.996 5.The detection limit was 4.75 × 10^-6 mol/L.The kinetic parameters of this processwere calculated.The diffusiong coefficient was 7.4 × 10-7cm^2/s.The heter ogeneouselectron transfer rate constant kf was 6.8 × 10^-4 cm/s,α value was 0.626 and electron transfer numbers was 2.