Abstract Recently Ni2+ and Co2+ incorporated MoS2 nanocatalysts demonstrated the superior HER performance compare to the pristine MoS2 nanostructures. Further investigation on the comparative HER behavior of these materials is required as there are only a few reports have been published so far. Here in, the HER performance of the Ni2+ and Co2+ incorporated MoS2 nanocatalysts (referred to as Ni-MoS2, Co-MoS2) compared with pristine MoS2 directly grown on carbon cloth via hydrothermal method. The SEM images revealed the distinguished morphology of Ni-MoS2, Co-MoS2 compare to pristine MoS2. The XPS and Raman studies confirmed the incorporation of transition metal ions in 2H phase of MoS2 lattice. Moreover, the transition metal ion incorporated MoS2 nanocatalyts showed a significant drop in overpotential (η10 @ j = 10 mA/cm2). The measured η10 was found lowest for Co-MoS2 (−58 mV) compare to Ni-MoS2 (−136 mV) and pristine MoS2 (−167 mV). The promoted HER activity in Co-MoS2, Ni-MoS2 analyzed by Tafel slope analysis and electrochemical impedance spectroscopy (EIS). The EIS measurements showed a significant increase in the active site density and lowering of the charge-transfer resistance (Rct), resulting in lower overpotential.

中文翻译：

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通过引入 Ni 和 Co 离子以增强 HER 活性的形态定制纳米结构 MoS2 催化剂

摘要 最近，与原始的 MoS2 纳米结构相比，Ni2+ 和 Co2+ 掺入的 MoS2 纳米催化剂表现出优异的 HER 性能。需要对这些材料的比较 HER 行为进行进一步研究，因为迄今为止仅发表了少数报告。在此，与通过水热法直接在碳布上生长的原始 MoS2 相比，Ni2+ 和 Co2+ 掺入了 MoS2 纳米催化剂（称为 Ni-MoS2、Co-MoS2）的 HER 性能。SEM 图像揭示了 Ni-MoS2、Co-MoS2 与原始 MoS2 相比的独特形态。XPS 和拉曼研究证实了过渡金属离子在 MoS2 晶格的 2H 相中的结合。此外，掺入过渡金属离子的 MoS2 纳米催化剂显示过电位显着下降（η10 @ j = 10 mA/cm2）。与 Ni-MoS2 (-136 mV) 和原始 MoS2 (-167 mV) 相比，Co-MoS2 (-58 mV) 的测量 η10 最低。通过 Tafel 斜率分析和电化学阻抗谱 (EIS) 分析 Co-MoS2、Ni-MoS2 中促进的 HER 活性。EIS 测量显示活性位点密度显着增加，电荷转移电阻 (Rct) 降低，导致过电位降低。