Trace amount of arsenate in the presence of arsenite was determined directly on pencil graphite electrode modified by graphene oxide and zirconium (Zr−G−PGE). The layer‐by‐layer modification of PGE was characterized by scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). Key point of the developed method was quick adsorption of arsenate than arsenite on the Zr−G−PGE. In optimal conditions, the Zr−G−PGE was applied for determination of arsenate using differential pulse voltammetry in a linear range 0.10–40.0 μg L⁻¹ with a limit of determination of 0.12±0.01 μg L⁻¹. The sensitivity of the electrode was 1.36±0.07 μA/μg L⁻¹. The modified electrode was used to measure the concentration of arsenate in the river water. A recovery test was performed by introducing 10 μg L⁻¹ arsenate into the rivers water in order and acceptable data of average recovery of 101.2 % was obtained. From the experimental results, the as‐prepared electrode can provide a satisfactory method for direct determination of arsenate in real samples.

中文翻译：

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氧化石墨烯和锆修饰的铅笔状石墨电极上砷存在下的时间分辨直接测定砷

直接在由氧化石墨烯和锆（Zr-G-PGE）修饰的笔形石墨电极上测定了在亚砷酸盐存在下的痕量砷酸盐。PGE的逐层修饰通过扫描电子显微镜（SEM），X射线光电子能谱（XPS）和循环伏安法（CV）进行表征。该方法的重点是在Zr-G-PGE上砷的吸附比砷的吸附快。在最佳条件下，使用Zr-G-PGE在0.10–40.0μgL ^-1的线性范围内使用差分脉冲伏安法测定砷酸盐，测定极限为0.12± 0.01μgL ^-1。电极的灵敏度为1.36±0.07μA/μgL ^-1。修饰的电极用于测量河水中砷的浓度。通过将10μgL ^-1砷酸盐依次引入河流水中进行了回收率测试，获得了可接受的平均回收率101.2％的数据。从实验结果来看，所制备的电极可以提供一种直接测定实际样品中砷酸盐的令人满意的方法。