Electrochemically activated glassy carbon electrodes were applied to the preconcentration and electroanalysis of metal species. Activated glassy carbon electrodes were obtained by potentiostatic oxidation at +2.0V in 0.5 M sulfuric acid. Copper species were readily extracted onto the modified electrode and were determined electrochemically. Voltammetric peak currents showed linear response for copper concentrations in the range between 1 to 20 mu M with a large slope of 2.11 A M-1 and a correlation coefficient of 0.997. The reproducibility of the voltammetric measurements was found to be within 7 % RSD for five replicate measurements on copper concentration of 10 mu M. The modified electrodes could be applied for repeated copper determinations without appreciable deterioration in electrode response. Results suggest that the preconcentration of copper species onto activated electrodes involved primarily cation-exchange interactions with the surface graphite oxide film.
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机译：将电化学活化的玻璃碳电极应用于金属种类的预浓缩和电分析。通过在+ 2.0V下于0.5 M硫酸中进行恒电位氧化，可获得活性玻璃碳电极。铜很容易提取到修饰的电极上，并进行电化学测定。伏安峰电流显示出铜浓度在1至20μM之间的线性响应，斜率为2.11 A M-1，相关系数为0.997。对于10μM的铜浓度进行五次重复测量，伏安法测量的可重复性在7％RSD之内。修饰的电极可用于重复测定铜，而电极响应不会明显下降。结果表明，铜物质在活性电极上的预富集主要涉及与表面氧化石墨膜的阳离子交换相互作用。
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