Abstract This study focuses on the covalent grafting of thin organic layers on a glassy carbon electrode by aryl diazonium salts containing functional groups capable of complexing Ni(II) ions. The goal was to develop a modified electrode for the detection of Ni(II) ions in aqueous media. The glassy carbon electrode (GCE) surface was modified by electrochemical reduction of diazonium salts synthesized in-situ in aqueous acid medium from 4-amino-benzamide (4-AB) and 4-amino-benzamide-oxime (4-ABO). XPS, AFM, ellipsometry and cyclic voltammetry were used for surface characterization of the grafted GCE. The barrier properties of the grafted layer were determined and compared by cyclic voltammetry, using Fe(CN)63−/4−, Ru(NH3)63+/2+ and dopamine redox probes in different pH media. The adsorptive properties of the grafted glassy carbon were compared for Pb(II), Cu(II) and Ni(II) cations. The ability of these modified GCE to detect Ni(II) ions was then explored using a two-step method: i) complexation of Ni(II) by the grafted layer, followed by ii) electroreduction of the complexed Ni(II) and then its analysis by anodic square wave voltammetry. The 4-ABO grafted glassy carbon electrodes were able to detect Ni(II) in micro-molar concentration. The presence of ions such as Pb2+, Mg2+, Ca2+, K+ and Na+ did not interfere with the Ni(II) quantification. The phenyl-oxime functionalized electrodes showed good robustness during more than fifty electroanalysis.

中文翻译：

---

苯酰胺肟和苯酰胺纳米层通过电还原相应的重氮盐共价接枝碳以检测镍离子

摘要 本研究的重点是通过含有能够络合 Ni(II) 离子的官能团的芳基重氮盐在玻璃碳电极上共价接枝薄有机层。目标是开发一种改进的电极，用于检测水介质中的 Ni(II) 离子。通过电化学还原在酸性水溶液介质中由 4-氨基-苯甲酰胺 (4-AB) 和 4-氨基-苯甲酰胺-肟 (4-ABO) 原位合成的重氮盐，对玻璃碳电极 (GCE) 表面进行了改性。XPS、AFM、椭圆光度法和循环伏安法用于接枝 GCE 的表面表征。接枝层的阻隔性能通过循环伏安法测定和比较，使用 Fe(CN)63-/4-、Ru(NH3)63+/2+ 和多巴胺氧化还原探针在不同 pH 介质中。比较了接枝玻璃碳对 Pb(II)、Cu(II) 和 Ni(II) 阳离子的吸附性能。然后使用两步法探索这些改性 GCE 检测 Ni(II) 离子的能力：i) 通过接枝层络合 Ni(II)，然后 ii) 电还原络合的 Ni(II)，然后阳极方波伏安法分析。4-ABO 接枝玻碳电极能够检测微摩尔浓度的 Ni(II)。Pb2+、Mg2+、Ca2+、K+ 和 Na+ 等离子的存在不会干扰 Ni(II) 的定量。苯基肟功能化电极在超过 50 次电分析中表现出良好的稳健性。i) 通过接枝层络合 Ni(II)，然后 ii) 电还原络合的 Ni(II)，然后通过阳极方波伏安法对其进行分析。4-ABO 接枝玻碳电极能够检测微摩尔浓度的 Ni(II)。Pb2+、Mg2+、Ca2+、K+ 和 Na+ 等离子的存在不会干扰 Ni(II) 的定量。苯基肟功能化电极在超过 50 次电分析中表现出良好的稳健性。i) 通过接枝层络合 Ni(II)，然后 ii) 电还原络合的 Ni(II)，然后通过阳极方波伏安法对其进行分析。4-ABO 接枝玻碳电极能够检测微摩尔浓度的 Ni(II)。Pb2+、Mg2+、Ca2+、K+ 和 Na+ 等离子的存在不会干扰 Ni(II) 的定量。苯基肟功能化电极在超过 50 次电分析中表现出良好的稳健性。