Abstract A simple chemical precipitation route was developed to synthesize CuNiO nanoparticles on graphite sheets [CuNiO/Gt] by forming both copper and nickel hydroxide species followed by their calcination at 400 °C for 3 h. X-ray diffraction and transmission electron microscopy were employed to characterize the crystallinity and morphology of fabricated CuNiO/Gt nanocomposite. The ability of this prepared powder to act as an active component inside modified carbon paste electrode (MCPE) for potentiometric determination of copper(II) ions in spiked water samples was investigated. The electrochemical performance of this MCPE was optimized by studying the effect of altering CuNiO content, response time and pH on the measured emf value. The prepared electrode exhibited a divalent Nernstian slope of 30.2 ± 1.80 mV decade−1 over Cu(II) ions concentration ranging from 1.0 × 10−6 up to 5.0 × 10−2 mol L−1. The optimum mass percent ratio of CuNiO:graphite:plasticizer in the prepared MCPE was found to be 0.424:0.279:0.297. A detection limit value of 1.0 × 10−6 mol L−1 was calculated. Cu(II) ions concentration in real water samples could be efficiently estimated using this synthesized MCPE with recovery values of 102−103%.

中文翻译：

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石墨负载CuNiO纳米颗粒的制备、表征和电化学应用，用于电位测定加标水样中的铜离子

摘要 开发了一种简单的化学沉淀路线，通过形成氢氧化铜和氢氧化镍物种，然后在 400 °C 下煅烧 3 小时，在石墨片 [CuNiO/Gt] 上合成 CuNiO 纳米颗粒。采用 X 射线衍射和透射电子显微镜来表征制备的 CuNiO/Gt 纳米复合材料的结晶度和形貌。研究了这种制备的粉末作为改性碳糊电极 (MCPE) 内的活性成分的能力，用于电位测定加标水样品中的铜 (II) 离子。通过研究改变 CuNiO 含量、响应时间和 pH 值对测量电动势值的影响，优化了该 MCPE 的电化学性能。制备的电极表现出 30.2 ± 1 的二价能斯脱斜率。Cu(II) 离子浓度范围从 1.0 × 10−6 到 5.0 × 10−2 mol L−1 范围内为 80 mV 十进制−1。发现制备的 MCPE 中 CuNiO:石墨:增塑剂的最佳质量百分比为 0.424:0.279:0.297。计算出的检测极限值为 1.0 × 10-6 mol L-1。使用这种合成的 MCPE 可以有效地估计实际水样中的 Cu(II) 离子浓度，回收率为 102-103%。