The scarcity and cost of noble metals used in commercial electrolyzers limit the sustainability and scalability of water electrolysis for green hydrogen production. Herein, we report the ultralow loading of Au nanoparticles onto MoS₂ electrodes by the spontaneous process of galvanic deposition. AuNP@MoS₂ electrode synthesis was optimized, and electrodes containing the smallest Au nanoparticle diameter (2.9 nm) and the lowest Au loading (0.044 μg cm^–2) exhibited the best overall and intrinsic electrocatalytic performance. This enhancement is attributed to an increased Au–MoS₂ interaction with smaller nanoparticles, making the MoS₂ electrode more n-type. DC electrochemical characterization for the AuNP@MoS₂ electrodes showed an exchange current density of 7.28 μA cm^–2 and an overpotential at 10 mA cm^–2 of −323 mV. These values are 4.5 times higher and 100 mV lower than those of the unmodified MoS₂ electrode, respectively. Electrochemical AC experiments were used to evaluate the electrodes’ intrinsic catalytic activity, and it was shown that the AuNP@MoS₂ electrodes exhibited an enhanced activity by as much as 3.5 times compared with MoS₂. Additionally, the turnover frequency as estimated by the reciprocal of the R_ctC_dl product, the latter calculated from the AC data, is estimated to be 58.8 s^–1 and is among one of the highest reported for composite MoS₂ materials.

中文翻译：

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具有自发超低金负载的高性能纳米结构 MoS2 电极，用于析氢

商业电解槽中使用的贵金属的稀缺性和成本限制了用于绿色氢生产的水电解的可持续性和可扩展性。在此，我们报告了通过电流沉积的自发过程将Au 纳米颗粒超低负载到 MoS ₂电极上。优化了AuNP@MoS ₂电极合成，含有最小Au纳米颗粒直径（2.9 nm）和最低Au负载量（0.044 μg cm ^–2）的电极表现出最佳的整体和本征电催化性能。这种增强归因于Au-MoS ₂与较小纳米颗粒的相互作用增加，使MoS ₂电极更加n 型。AuNP@MoS 的直流电化学表征_{2 个}电极显示出 7.28 μA cm ^–2的交换电流密度和-323 mV 的10 mA cm ^–2过电位。这些值分别比未改性的 MoS ₂电极高 4.5 倍和低 100 mV 。电化学交流实验用于评估电极的固有催化活性，结果表明，AuNP@MoS ₂电极的活性比MoS ₂提高了3.5倍。此外，根据R _ct C _dl乘积的倒数估计的周转频率，后者根据 AC 数据计算，估计为 58.8 s ^–1并且是对复合MoS ₂材料报道最高的材料之一。