二乙腈基二硫纶在金电极上的自组装及其对抗坏血酸的电化学行为研究

Na_2[Ni(mnt)_2]Self-assemble Monolayer on Gold Electrode and Its Application in the Electrocatalytic Oxidation of Ascorbic Acid

将Na2ENi（mnt）2]（mnt=丁二腈烯二硫醇阴离子）自组装到裸金电极表面，制成mnt—SAM／Au修饰电板，并用电化学方法研究了该修饰电极的电化学性质。实验结果表明，mnt—SAM膜对[Fe（CN）6]3-/[Fe（CN）6]4-有一定的排斥作用，而对[Co（phen）3]2＋/[Co（phen）。一有一定吸引作用。研究了抗坏血酸（AA）在自组装膜修饰金电极上的电化学氧化行为，考察了溶液pH、扫描速率的影响，结果表明该膜对AA的氧化具有催化作用。在最佳条件下，峰电流与AA的浓度在5．0×10～1．3×10-3mool·L-1范围内呈良好的线性关系，相关系数为～0．9987，检测限为1．0×10-6mol·L-1。

A gold electrode modified with Na2 Ni-mnt self-assembled monolayer has been prepared. The electrode reaction was investigated by electrochemical method. The electrode reaction for [Fe（CN）6 ]3 /[Fe（CN）6 ]4- was efficiently inhibited by the mnt cavity. However, the diffusion of [Co（phen）3 ]z＋/[Co（phen）3 ]3＋ to the electrode surface can be enhanced due to the same charge with Na2Ni-mnt monolayers. At the same time, the effect of the pH value, the scan rate and the concentration of the solution on the redox of ascorbic acid were also studied. The results indicated that the mnt-SAM modified electrode had the electrocatalytic property toward the oxidation of AA. The oxidation peak current can be used for the determination of AA in the range of 5.0 × 10-6-1.3 × 10-3 moloL -1 with the correlation coefficient of -0. 9987, and the detection limit of 1.0× 10 6mol·L-1.