Gold-mercury (AuHg) nanochains were successfully synthesized based on the tip effect of Au NRs. Chained gold-mercury-platinum (AuHgPt) nanoalloys were prepared by the galvanic replacement reaction (GRR) using the AuHg nanochains as templates at room temperature and used to study the electrochemical properties in hydrogen evolution reaction (HER). The morphologies, structures, compositions, and electronic effects of the AuHgPt nanochains were investigated, and the hydrogen evolution properties of the nanomaterials were electrochemically evaluated. The results of HER polarization curves in an alkaline solution showed that the overpotential required for the AuHgPt nanochains to reach a current density of 10 mA·cm-2 was only 23 mV and the Tafel slope was 47.72 mV·dec-1, both of which were lower than that of commercial Pt/C (27 mV, 54.11 mV·dec-1). Moreover, the loss of current density at a current density of 50 mA·cm-2 after a long period of 24 h was only 2.5 mV·dec-1. The loss of current density was only 2.8% after a long-time test at 50 mA·cm-2. The synergistic interactions between the alloyed metals resulted in the nanochains exhibiting excellent HER electrocatalytic activity and stability. In addition, the density functional theory (DFT) calculations were employed to analyze the Gibbs free energies related to water dissociation and H2 desorption on different nanoalloys, along with the d-band center (εd) for these materials, which indicate that the enhanced water dissociation ability stems from an interaction between the intensified OH-Au and the diminished H-Pt bonds. This conclusion is supported by the observed elevation in the average εd values of Au and Pt atoms within the AuHgPt nanoalloy.

中文翻译：

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基于汞齐的 AuHgPt 纳米链作为析氢反应的电催化剂


基于Au NRs的尖端效应成功合成了金-汞-铂（AuHg）纳米链。在室温下，以AuHg纳米链为模板，通过电偶置换反应（GRR）制备了链状金-汞-铂（AuHgPt）纳米合金，并用于研究析氢反应（HER）中的电化学性质。研究了 AuHgPt 纳米链的形态、结构、组成和电子效应，并对纳米材料的析氢特性进行了电化学评价。碱性溶液中HER极化曲线结果表明，AuHgPt纳米链达到10 mA·cm-2电流密度所需的过电位仅为23 mV，塔菲尔斜率为47.72 mV·dec-1，均低于商用Pt/C的过电位（27 mV，54.11 mV·dec-1）。此外，在电流密度为 50 mA·cm-2 时，长时间 24 h 后电流密度的损失仅为 2.5 mV·dec-1。在 50 mA·cm-2 下长时间测试后，电流密度损失仅为 2.8%。合金金属之间的协同作用导致纳米链表现出优异的 HER 电催化活性和稳定性。此外，采用密度泛函理论 （DFT） 计算来分析不同纳米合金上与水解离和 H2 解吸相关的吉布斯自由能，以及这些材料的 d 波段中心 （εd），这表明增强的水解离能力源于增强的 OH-Au 和减弱的 H-Pt 键之间的相互作用。观察到的 AuHgPt 纳米合金中 Au 和 Pt 原子的平均 εd 值升高支持了这一结论。