Abstract We investigate the effect of single-atom doping on the hydrogen evolution reaction (HER) activity of MoS2 using first-principles calculations. In Ru-doped MoS2 that was recently suggested as a promising HER catalyst, we show that sulfur vacancy (VS) prefers to form defect complexes with Ru substituting for Mo (RuMo). We examine hydrogen adsorption free energy at various potential active sites, which underlines that VS in the defect complex can serve as important active centers for HER. We also examine various transition-metal (TM) dopants for MoS2. The results show that several TMs such as Sn, Tc, Ir, Rh, Ru, Re, Os, Pd, and Pt can be used as dopants to promote the HER process on MoS2. By uncovering the active sites for HER in single-atom doped MoS2 as well as suggesting several promising dopants, this work will open the way to developing novel 2D catalysts for HER.

中文翻译：

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MoS2 电催化剂中过渡金属掺杂剂与硫空位之间的相互作用

摘要 我们使用第一性原理计算研究了单原子掺杂对 MoS2 析氢反应 (HER) 活性的影响。在最近被建议作为一种有前途的 HER 催化剂的 Ru 掺杂的 MoS2 中，我们表明硫空位 (VS) 更喜欢与 Ru 取代 Mo (RuMo) 形成缺陷配合物。我们检查了各种潜在活性位点的氢吸附自由能，这表明缺陷复合物中的 VS 可以作为 HER 的重要活性中心。我们还研究了 MoS2 的各种过渡金属 (TM) 掺杂剂。结果表明，Sn、Tc、Ir、Rh、Ru、Re、Os、Pd 和 Pt 等几种 TM 可用作掺杂剂以促进 MoS2 上的 HER 过程。通过揭示单原子掺杂的 MoS2 中 HER 的活性位点以及提出几种有前景的掺杂剂，