A dual strategy that the L‐cysteine self‐assembling on three‐dimensional network of organic‐hybrid‐materials realized by successive interaction of Au−S bond is employed to construct as the amplified electrochemical sensor for determination Cu (II). Specifically, the sensor combined a rigid three‐dimension inorganic net which provides a higher interfacial area as well as faster adsorption of ions. Accordingly, surface and interfacial‐dominated electro‐catalysis reactivity is used as an ideal test‐bed to verify the reliability of electrochemical sensor that reveal enhancement sensitiveness and selectivity, low detection limit, and stability over a long period of time. Time‐dependent density functional theory (TD‐DFT) were used to calculating the all complexes energies at the B3LYP/LANL2DZ level associated with the polarized continuum model (PCM). The result of calculation indicates that the binding strength of Cu (II), Cd (II), As (III), Hg (II) with L‐cysteine are decrease successively, and this is in well agreement with experimental results. This work not only achieves an unprecedented understanding to L‐cysteine/Au/TiO₂/GCE sensor but also provides a new perspective for application in detection of Cu (II) in real river waters.

中文翻译：

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有机-无机-杂化-增强电化学传感器测定河水中的铜（II）

通过Au-S键的连续相互作用实现的L-半胱氨酸在有机杂化材料三维网络上自组装的双重策略被用作构建用于测定Cu（II）的放大电化学传感器。具体来说，该传感器结合了刚性的三维无机网，该网提供了更大的界面面积以及更快的离子吸附能力。因此，表面和界面主导的电催化反应性被用作理想的试验台，以验证电化学传感器的可靠性，该传感器显示出增强的灵敏度和选择性，低的检测限以及长期的稳定性。随时间变化的密度泛函理论（TD-DFT）用于计算与极化连续谱模型（PCM）相关的B3LYP / LANL2DZ能级的所有络合物能。计算结果表明，Cu（II），Cd（II），As（III），Hg（II）与L-半胱氨酸的结合强度依次降低，与实验结果吻合良好。这项工作不仅对L-半胱氨酸/ Au / TiO有了前所未有的了解₂ / GCE传感器，但也为在实际河水中检测Cu（II）提供了新的视角。