Copper ions (Cu2+) pollution in the water environment poses a great threat to the health function of life-sustaining metabolic activities. However, the current detection methods need relatively expensive instruments, complex operation procedures and long time, so a facile and direct detection method is desired to be developed. In this work, the Ni-based composite wires with p-n junction (the Ni/NiO/ZnO/Chitosan wire) and Schottky junction (the Ni/NiO/Au/Chitosan wire) were fabricated, and the barrier driven electrochemical sensing mechanism was studied. The direct and facile detection of Cu2+ was achieved with a wide linear range (0-6000 nM) and a low LOD (0.81 nM). The excellent stability and recovery in real water samples made the Ni-based composite wires a promising candidate for the practical application. The interfacial barriers of semiconductor can be used as a special sensing factor to develop novel sensors.

中文翻译：

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用于电化学检测铜（Ⅱ）离子的镍基复合导线的制备

水环境中的铜离子 (Cu2+) 污染对维持生命的代谢活动的健康功能构成巨大威胁。然而，目前的检测方法需要相对昂贵的仪器、复杂的操作程序和较长的时间，因此需要开发一种简便、直接的检测方法。在这项工作中，制备了具有 pn 结（Ni/NiO/ZnO/壳聚糖线）和肖特基结（Ni/NiO/Au/壳聚糖线）的 Ni 基复合线，并研究了势垒驱动的电化学传感机制. Cu2+ 的直接和轻松检测是通过宽线性范围 (0-6000 nM) 和低 LOD (0.81 nM) 实现的。在实际水样中优异的稳定性和回收率使镍基复合线材成为实际应用的有希望的候选者。