2-巯基乙醇自组装膜电极的制备及其电化学性质

Preparation and Electrochemical Properties of 2-Mmercaptoethanol Self-assembled Monolayer Modified Gold Electrode

在裸 Au电极上制备了 2 -巯基乙醇自组装膜电极 (ME/Au SAMs) ,研究了该电极催化米吐尔和对苯二酚氧化的电化学行为 ,发现该膜加速了电子传递速率 ,测得米吐尔和对苯二酚的扩散系数分别为 D米2 .1× 1 0 -5cm2 /s、D对 2 .7× 1 0 -6cm2 /s,初步探讨了电催化机理 .采用水平衰减全反射 -傅立叶变换红外光谱(ATR-FTIR)技术对 ME/Au SAMs进行了表征 ,示差脉冲伏安法 (DPV)同时测定米吐尔和对苯二酚 ,不产生干扰 ,其氧化峰电流与相应物质的浓度分别在 1 .0× 1 0 -7～ 1 .0× 1 0 -4mol/L 和 6.0× 1 0 -6～ 6.0×1 0 -4mol/L范围内呈良好的线性关系 ,相关系数分别为 0 .9992和 0 .9996,检测限分别为 2 .0× 1 0 -8和 1 .2×1 0 -6mol/L .该电极用于黑白显影液中米吐尔和对苯二酚的同时测定 ,结果满意 .

Mercaptoethanol self assembled monolayer modified gold electrode(ME/Au SAMs) has been fabricated. The electrochemical behavior of metol ( N methyl p aminophenol sulfate) and p benzenediol at ME/Au SAMs have been studied. The modified electrode shows an excellent electrocatalytic activity for the oxidation of metol and p benzenediol, and accelerates electron transfer rate. Diffusion coefficients for metol and p benzenediol were 2 1×10 -5 cm 2/s and 2 7×10 -6 cm 2/s, respectively . The electrocatalysis mechanism has been studied. ATR FTIR was used for the characterization of the ME/Au SAMs. The oxidation currents were linear in the range of 1 0×10 -7 ~1 0×10 -4 mol/L for metol and 6 0×10 -6 ~6 0×10 -4 mol/L for p benzenediol, with the correlation coefficients of 0 999 2 and 0 999 6 by differential pulse voltammetry(DPV), and detection limit 2 0× 10 -8 mol/L and 1 2×10 -6 mol/L for metol and p benzenediol, respectively. The modified electrode can be used for the simultaneous determination of metol and p benzenediol in photographic imaging agents . The method is simple, quick, sensitive and accurate.