There has been a substantial research effort worldwide to develop non-noble metal catalysts for H₂ production from water splitting using renewable energy sources, but most data were evaluated by voltammetry in laboratories. Here, exposed basal planes of MoS₂ monolayer nanosheets with metal dopants across the first transition metal (TM) series in the periodic table (Fe, Co, Ni, Cu) are used as cathode catalysts for the proton-exchange membrane (PEM) water splitting in an electrolyzer under typical conditions of strong acidity with more negative applied voltage. Extended X-ray absorption fine structure spectroscopy (EXAFS) analysis and high-angle annular dark-field scanning transmission electron microscopy (HAADF–STEM) images show a direct proof on the single TM atoms residing at the surface basal sites, which subtly modify the electrocatalytic activity of the monolayer MoS₂, depending on their electronic and metal-hydrogen binding ability. We report that Co-^sMoS₂ yields the highest current density in an electrolyzer with the hydrogen evolution reaction (HER) activity comparable with that of the commercial 20 wt% Pt/C under industrial applicable conditions. A general trend for the other TMs has also been established as evidenced by the change in TM effective nuclear charge across the periodic table, which perturbed the TM-Mo interaction and hence affects the HER activity.

世界范围内已经进行了大量的研究工作，以开发使用可再生能源从水分解产生H _2的非贵金属催化剂，但是大多数数据是通过伏安法在实验室中评估的。在这里，MoS _2的暴露基面元素周期表中第一过渡金属（TM）系列中具有金属掺杂剂的单层纳米片（Fe，Co，Ni，Cu）用作质子交换膜（PEM）在常规条件下电解器中水分解的阴极催化剂强酸性，负电压更大。扩展的X射线吸收精细结构光谱学（EXAFS）分析和高角度环形暗场扫描透射电子显微镜（HAADF–STEM）图像显示了存在于表面基础位点上的单个TM原子的直接证据，这些分子巧妙地修饰了单层MoS ₂的电催化活性取决于它们的电子和金属-氢结合能力。我们报告说，合作^小号的MoS ₂在工业适用条件下，在具有氢释放反应（HER）活性的电解槽中产生的最高电流密度与市售20 wt％Pt / C相当。还已经建立了其他TMs的总体趋势，这可以通过周期表中TM有效核电荷的变化来证明，这会干扰TM-Mo相互作用并因此影响HER活性。