Defects on nanomaterials can effectively enhance the performance of electrochemical detection, but an excessive number of defects may have an adverse effect. In this study, MoS nanosheets were synthesized using a hydrothermal synthesis method. By controlling the calcination temperature, MoS–7H, calcined at 700 °C under H/Ar, exhibited an optimal ratio of “point” defects to “plane” defects, resulting in excellent detection performance for mercury ions (Hg(II)). In general, the sulfur vacancies (SV) and undercoordinated Mo generated after calcination of MoS significantly promotes the adsorption process and redox of Hg(II) by increasing surface chemical activity, providing additional adsorption sites and adjusting surface charge status to accelerate the catalytic redox of Hg(II). The prepared MoS–7H-modified electrode showed a sensitivity of 18.25 μA μM and a low limit of detection (LOD) of 6.60 nM towards Hg(II). MoS–7H also demonstrated a good anti-interference, stability, and exhibited a strong current response in real water samples. The modulation to obtain appropriate number of defects in MoS holds promise as a prospective electrode modification material for the electroanalysis.

中文翻译：

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基于MoS2缺陷数量的高效Hg(II)电化学检测：洞察硫空位和欠配位Mo的协同作用


纳米材料上的缺陷可以有效增强电化学检测的性能，但过多的缺陷可能会产生不利影响。本研究采用水热合成法合成了MoS2纳米片。通过控制煅烧温度，在 H/Ar 下于 700 °C 下煅烧的 MoS-7H 表现出最佳的“点”缺陷与“面”缺陷比例，从而对汞离子 (Hg(II)) 具有优异的检测性能。一般来说，MoS煅烧后产生的硫空位（SV）和欠配位Mo通过增加表面化学活性、提供额外的吸附位点和调节表面电荷状态来加速Hg(II)的催化氧化还原，从而显着促进Hg(II)的吸附过程和氧化还原。汞(II)。制备的 MoS-7H 修饰电极对 Hg(II) 的灵敏度为 18.25 μA μM，检测下限 (LOD) 为 6.60 nM。 MoS-7H还表现出良好的抗干扰性、稳定性，并在实际水样中表现出较强的电流响应。通过调制获得适当数量的 MoS2 缺陷，有望成为用于电分析的有前景的电极修饰材料。