The exploration of two-dimensional (2D) metallenes is driven by their noteworthy attributes, encompassing high conductivity and substantial exposure of metal active sites, facilitating the development of nitrogen reduction reaction (NRR) electrocatalysts characterized by low overpotential and superior selectivity. Here, employing first-principles swarm-intelligence structural search methods, we predict molybdenene as a novel and stable non-precious metallene, featuring a 2-atoms-thick structure. Our findings demonstrate that the basal plane of molybdenene showcases remarkable catalytic activity with an overpotential of 0.27 V. Bader charge analysis reveals that the exposed Mo bonded to NxHy groups not only transfer electrons to these groups but also the remaining Mo transfer electrons to NxHy upon the breaking of N≡N bond. This electron transfer mechanism contributes to elevated NRR catalytic activity. Our work broadens the scope of metallene as promising electrocatalysts for NRR in the expectation that more attention will be paid to emerging metallenes, thus offering a modest contribution to the theoretical exploration, fundamental understanding and practical application for metallenes.

中文翻译：

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新型二维钼作为有前途的氮还原反应电催化剂：第一性原理预测


二维 （2D） 金属的探索由其值得注意的属性驱动，包括高导电性和金属活性位点的大量暴露，促进了具有低过电位和卓越选择性的氮还原反应 （NRR） 电催化剂的开发。在这里，采用第一性原理群体智能结构搜索方法，我们预测钼烯是一种新颖且稳定的非贵金属，具有 2 原子厚的结构。我们的研究结果表明，钼烯的基平面表现出显着的催化活性，过电位为 0.27 V。Bader 电荷分析表明，暴露的 Mo 与 NxHy 基团键合不仅将电子转移到这些基团，而且剩余的 Mo 在 N≡N 键断裂时也将电子转移到 NxHy。这种电子转移机制有助于提高 NRR 催化活性。我们的工作拓宽了金属烯作为有前途的 NRR 电催化剂的范围，以期更多地关注新兴的金属烯，从而为金属烯的理论探索、基本理解和实际应用做出适度的贡献。