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制备了磷钼杂多酸－Ｌ－半胱氨酸自组装超分子膜电极（Ｐ２Ｍｏ１８－Ｌ－Ｃｙｓ／Ａｕ）。采用水平衰减全反射（ＡＴＲ－ＦＴＩＲ）光谱表征了膜的组成。研究了该膜电极的电化学性质，发现它在１．０ ｍｏｌ／Ｌ Ｈ２ＳＯ４溶液中，于０．０～０．７Ｖ（ｖｓ．ＳＣＥ）间ＣＶ扫描出现两对稳定、可逆的氧化还原峰，其中峰电位分别为Ｅｍ１＝０．３３４ Ｖ，Ｅｍ２＝０．１８８Ｖ，对应着Ｐ２Ｍｏ１８Ｏ_(６２)~(６－)的两步２电子－２质子反应；计时库仑法计算了薄膜内的电子传递系数Ｄ为５．０１ × １０~（－８）ｃｍ２·ｓ～（－１）。该膜电极对酸性溶液中的ＮＯ_２~－有明显的电催化还原作用，初步探讨了电催化机理。用差分脉冲伏安法（ＤＰＶ）测定其还原峰电流与ＮＯ_２~－的浓度在２．０ ×１０~（－６）～２．０ × １０~（－４）ｍｏｌ／Ｌ范围内呈良好的线性关系，相关系数为０．９９５３，检测限５．０×１０~（－７）ｍｏｌ／Ｌ。该电极用于模拟水样中ＮＯ_２~－的测定，结果满意。
A phosphomolybdic heteropoly-L-cysteine self-assembled supramolecular membrane electrode (P2Mo18-L-Cys / Au) was prepared. The composition of the membrane was characterized by ATR-FTIR spectroscopy. The electrochemical properties of the membrane electrode were investigated and it was found that there were two pairs of stable and reversible redox peaks in CV scan between 0.0 and 0.7 V (vs.SCE) in 1.0 mol / L H2SO4 solution. The peak potentials were Em1 = 0.334 V and Em2 = 0.188 V, corresponding to the two-step2electron-2 proton reaction of P2Mo18O_ (62) ~ (6-) .The chronocoulometry method was used to calculate the electron transfer coefficient D is 5.01 × 10 ~ (-8) cm2 · s ~ (-1). The membrane electrode has obvious electrocatalytic reduction effect on NO 2 - in acidic solution, and the electrocatalytic mechanism was discussed preliminarily. The peak current and the concentration of NO_ (2) were measured by differential pulse voltammetry (DPV) in the range of 2.0 × 10 -6 -6.0 × 10 -4 mol / L The correlation coefficient was 0.9953 and the detection limit was 5.0 × 10 ~ (-7) mol / L. The electrode was used to simulate the determination of NO 2 - in water samples with satisfactory results.