Two-dimensional (2D) transition metal carbides/nitrides (MXenes) materials exhibit potential as catalysts for the hydrogen evolution reaction (HER) due to their large surface area, excellent conductivity, and notable electrical properties. Despite these advantages, pristine MXenes often display insufficient catalytic activity compared to noble metal electrocatalysts. Enhancing the HER performance of MXenes by introducing nonmetal atoms on the surface has proven effective. However, understanding the precise regulation of the HER performance by nonmetal atoms remains challenging. In this study, we utilized density functional theory calculations to explore how the introduction of fourteen distinct nonmetal atoms into MoCO catalysts (NM-MoCO) influences the catalytic behavior in HER. The results indicated that nonmetal atom doping significantly activates oxygen atoms, substantially enhancing catalytic activity. Notably, the addition of nonmetal atoms like chlorine (Cl), bromine (Br), and iodine (I) onto the MoCO surface effectively improved HER activity, showcasing their potential as HER catalysts. Our study proved that nonmetal atom doping not only causes localized structural distortions but also charge redistribution, influencing the HER performance of NM-MoCO. Furthermore, we developed two descriptors to quantify the regulation mechanism of nonmetal atoms, successfully predicting the HER activity of NM-MoCO and extending these insights to NM-CrCO and NM-VCO. These findings offer a comprehensive understanding of how nonmetal atom doping enhances HER activity, providing valuable insights for innovative catalyst design.

中文翻译：

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用于增强析氢反应活性的非金属改性二维碳化钼 (MXene)：DFT 研究

二维 (2D) 过渡金属碳化物/氮化物 (MXenes) 材料由于其大表面积、优异的导电性和显着的电性能，具有作为析氢反应 (HER) 催化剂的潜力。尽管具有这些优点，但与贵金属电催化剂相比，原始 MXene 通常表现出不足的催化活性。通过在表面引入非金属原子来增强 MXene 的 HER 性能已被证明是有效的。然而，了解非金属原子对 HER 性能的精确调节仍然具有挑战性。在这项研究中，我们利用密度泛函理论计算来探索将十四种不同的非金属原子引入MoCO催化剂（NM-MoCO）如何影响HER中的催化行为。结果表明，非金属原子掺杂显着激活了氧原子，大大提高了催化活性。值得注意的是，在MoCO表面添加氯（Cl）、溴（Br）和碘（I）等非金属原子有效提高了HER活性，展示了它们作为HER催化剂的潜力。我们的研究证明，非金属原子掺杂不仅会导致局部结构变形，还会导致电荷重新分布，从而影响 NM-MoCO 的 HER 性能。此外，我们开发了两个描述符来量化非金属原子的调控机制，成功预测了 NM-MoCO 的 HER 活性，并将这些见解扩展到 NM-CrCO 和 NM-VCO。这些发现提供了对非金属原子掺杂如何增强 HER 活性的全面了解，为创新催化剂设计提供了宝贵的见解。