Near-electrode pH change for voltammetric detection of insoluble lead carbonate
Near-electrode pH change for voltammetric detection of insoluble lead carbonate
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DOI：
10.1016/j.aca.2021.339087
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发表时间：
2021-09-30
影响因子：
6.2
通讯作者：
Alvarez, Noe T.
中科院分区：
文献类型：
--
作者：
Huseinov, Artur;Weese, Benjamin L.;Alvarez, Noe T.
饮用水的铅污染是老城区所有居民都关心的问题，那里仍然存在铅管和铅焊。简单的现场电化学检测方法是近年来备受关注的有前途的技术。然而，传统的电化学技术只能定量水中可溶形式的铅，而不考虑不溶性颗粒。本文报道了一种简单的伏安法测定不溶性铅的方法。以碳酸铅（PbCO3）为模型化合物，展示了不经化学处理直接在溶液中检测颗粒物铅的可能性。具体来说，电化学生成质子被用作溶解PbCO3的替代方法，从而获得更现实的铅污染评估。采用阴极剥离方波伏安法（CSSWV）检测铅。将高氧化电位施加到电极上后，电极浸泡在含有固体PbCO3颗粒的PbCO3溶液中，与饱和PbCO3溶液相比，观察到电流显著增加。信号与PbCO3的加入量成正比，即使超过了溶解度极限。因此，结合局部pH变化和CSSWV为原位检测不溶性铅提供了一种简单、快速、无试剂的方法。(C) 2021 Elsevier B.V.版权所有
Lead contamination of drinking water is a concern to all inhabitants of old cities where lead pipes and soldering are still present. Simple on-site electrochemical detection methods are promising technologies that have gained attention recently. However, conventional electrochemical techniques only quantify soluble forms of lead in water without accounting for insoluble particulates. Herein, a simple voltammetric technique for quantification of insoluble lead species is reported. Lead carbonate (PbCO3) was used as a model compound to show the possibility of detecting particulate lead species directly in solution without chemical treatment. Specifically, electrochemical generation of protons was used as an alternative method to dissolve PbCO3 and thus obtain a more realistic assessment of lead contamination. Lead was detected using cathodic stripping square wave voltammetry (CSSWV). After applying a high oxidizing potential to the electrode immersed in a PbCO3 solution with solid PbCO3 particulates, a significant increase in current was observed as compared to that of a saturated PbCO3 solution. The signal was proportional to the amount of added PbCO3, even when the solubility limit was exceeded. Thus, the combination of a local pH change with CSSWV provides a simple, rapid, and reagentless method for an in-situ detection of insoluble lead species. (C) 2021 Elsevier B.V. All rights reserved.