Although transition metal sulfides have presented prospect in electrochemical sensing, their electrocatalytic performance still cannot meet the demands for practical applications due to the difficulties in mass transport and electron transfer. In this work, double-shelled CuS nanocages (2-CuS NCs) were prepared for enzyme-free ascorbic (AA) sensor through a Cu2O- templated method. The unique double-shelled hollow structure displayed large specific surface areas, ordered diffusion channels, increased volume occupying rate, and accelerated electron transfer rate, resulting in enhanced electrochemical dynamic. As a sensing electrode for AA, 2-CuS NCs modified glassy carbon electrode (2-CuS NCs/GCE) exhibited eminent electrocatalytic activity in terms of satisfying sensitivity (523.7 μA mM-1 cm-2), short response time (0.31 s), and low limit of detection (LOD, 0.15 μM). 2-CuS NCs look promising for analytical sensing of AA in electrochemical sensors thanks to its prominent electrocatalytic kinetics issued from double-shelled hollow porous structure.

中文翻译：

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双壳 CuS 纳米笼设计优化电催化动力学以灵敏检测抗坏血酸。

尽管过渡金属硫化物在电化学传感方面具有广阔的前景，但由于传质和电子转移的困难，其电催化性能仍然不能满足实际应用的要求。在这项工作中，通过 Cu2O 模板方法制备了用于无酶抗坏血酸 (AA) 传感器的双壳 CuS 纳米笼 (2-CuS NCs)。独特的双壳中空结构表现出较大的比表面积、有序的扩散通道、增加的体积占有率和加速的电子转移速率，从而增强了电化学动力学。作为AA传感电极，2-CuS NCs修饰玻碳电极（2-CuS NCs/GCE）表现出优异的电催化活性，灵敏度高（523.7 μA mM-1 cm-2），响应时间短（0.31 s）和检测下限（LOD，0.15 μM）。2-CuS NC 由于其双壳中空多孔结构具有突出的电催化动力学特性，因此在电化学传感器中的 AA 分析传感方面看起来很有前景。