Abstract Electrochemical performance of methyl parathion (MP) at a boron-doped diamond (BDD) electrode was investigated in aqueous media by cyclic voltammetry (CV) and square wave voltammetry (SWV). Methyl parathion (MP) shows electroactivity on BDD electrodes, three peaks being registered corresponding to one oxidation (0.16 V) and two reduction peaks, at −0.53 V and 0.01 V. MP reduction is certainly pH-dependent. However, at pH > 9.0 the electrochemical reduction of MP involves a reversible reaction of one electron forming the nitro-anion radical (NAR). The nitro-anion radical undergoes disproportionation and its kinetic stability was evaluated by using a peak current ratio corresponding to the reversible pair R − NO2/R − NO2•−, and the second-order constant (k2) was determined. Moreover, thermodynamic parameters regarding the MP reduction mechanism and nitro-anion radical generation were investigated by computational methods.

中文翻译：

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金刚石电极应用于水介质中甲基对硫磷产生硝基阴离子自由基的伏安法

摘要 通过循环伏安法 (CV) 和方波伏安法 (SWV) 在水性介质中研究了甲基对硫磷 (MP) 在硼掺杂金刚石 (BDD) 电极上的电化学性能。甲基对硫磷 (MP) 在 BDD 电极上显示出电活性，记录了三个峰，对应于一个氧化 (0.16 V) 和两个还原峰，分别位于 -0.53 V 和 0.01 V。MP 的还原肯定取决于 pH 值。然而，在 pH > 9.0 时，MP 的电化学还原涉及一个电子形成硝基阴离子自由基 (NAR) 的可逆反应。硝基阴离子自由基发生歧化，并通过使用对应于可逆对 R-NO2/R-NO2•- 的峰值电流比评估其动力学稳定性，并确定二级常数 (k2)。而且，